protein Archives - Health Tips From The Professor

600th Issue Celebration

November 5, 2024 by Dr. Steve Chaney

Nutrition Advances Over The Last Two Years

Author: Dr. Stephen Chaney

In the nearly twelve years that I have been publishing “Health Tips From The Professor”, I have tried to go behind the headlines to provide you with accurate, unbiased health information that you can trust and apply to your everyday life.

The 600^th issue of any publication is a major cause for celebration and reflection – and “Health Tips From The Professor” is no different.

I am dedicating this issue to reviewing some of the major stories I have covered in the past 100 issues. There are lots of topics I could have covered, but I have chosen to focus on three types of articles:

Articles that have debunked long-standing myths about nutrition and health.

Articles that have corrected some of the misinformation that seems to show up on the internet on an almost daily basis.

Articles about the issues that most directly affect your health.

Here are my picks from the last two years:

Weight Loss Diets

Since it is almost January, let’s start with a couple of articles about diet and weight loss (or weight gain). I have covered the effectiveness of the Paleo, Keto, Mediterranean, DASH, vegetarian, and Vegan diets for both short and long-term weight loss in my book “Slaying The Food Myths”, so I won’t repeat that information here. Instead, I will share a few updates from the past 100 issues.

Is Time-Restricted Eating Better Than Other Diets? Time-restricted eating is one of the latest fads. But is it really better than other diets for weight loss and improved health? In this article I reviewed two studies that compare time-restricted eating with diets that do not restrict time of eating but cut calories to the same extent. You may be surprised at the results.

Can You Lose Weight Without Dieting? In this article I share 8 tips for losing weight without going on a diet. The article is based on research by Dr. Brian Wansink, a behavioral psychologist who specializes in studying how external clues influence our eating patterns. As you might suspect his 8 tips for losing weight have nothing to do with counting calories or going on restrictive diets.

Healthy Diets

Is Whole Fat Dairy Healthy? For years dietary guidelines have been telling us to select low fat dairy foods. But some health gurus are telling you that isn’t true. They claim whole fat dairy is healthy. So, you are probably wondering, “What is the scoop (as in ice cream) on whole fat dairy?” In this article I look at the study behind the headlines and answer that question. But the answer is not a simple “Yes” or “No”. The answer is more nuanced. It turns out that whole fat dairy is healthier in some diets than in others.

Are Low Carb Diets Healthy? Are low carb diets good for you or bad for you? It depends on which study you quote. Two major studies in recent years have come to opposite conclusions. In this article I help you sort through the conflicting studies and rephrase the question. Instead of, “Are low carb diets healthy”, the question should be, “Which low carb diets are healthy?”

Are All Plant-Based Diets Healthy? Plant-based diets have acquired a “health halo” in recent years. Your mama told you to eat your fruits and vegetables. And many health gurus have been telling you not to neglect your grains, legumes, nuts, and seeds as well. But some of these foods require a lot of food preparation.

Never fear! The food industry has come to your rescue with a wide variety of processed plant-based foods. No need for food prep. But are they as good for you as the unprocessed plant foods they replace? In this article I review a study that answers that question.

You probably know what that answer is, but the article is worth a read anyway. That is because the study also asks whether vegan and vegetarian diets are healthier than other primarily plant-based diets. And you may not know the answer to that question.

Diet And Heart Disease

Are Eggs Bad For You? For years we were told that eggs are bad for us because they contain cholesterol. Then we were told that eggs in moderation may not increase our risk of heart disease. And recently studies have appeared claiming eggs may be good for our hearts. What is the truth about eggs and heart disease? In this article I review a recent study claiming eggs are bad for our heart and put that study into the context of other recent studies to clear up the “eggfusion”.

Which Diets Are Heart Healthy? Every popular diet claims to help you lose weight, reduce your risk of diabetes, and reduce your risk of heart disease. All these claims can’t be true. Which diets deliver on their promises, and which are just pretenders? In this article I review a recent study that answered that question for heart disease.

This study was a very large metanalysis of over 40 studies with 35,548 participants that looked at the effect of different diets on heart disease outcomes. The study identified two diets that significantly reduced the risk of heart disease. There are other diets that might reduce the risk of heart disease, but their benefits have not been proven by high quality clinical studies. They are merely pretenders.

The Dangers Of Processed Foods

In previous issues of “Health Tips From the Professor” I have shared articles showing that diets high in processed foods are associated with an increased risk of obesity, diabetes, and heart disease. But the story keeps getting worse. Here are two articles on recent studies about processed foods that appeared in “Health Tips From The Professor” in the last two years.

Why Does Processed Food Make You Fat? We already know that eating a lot of highly processed food is likely to make us fat. But what is it about processed food that makes us fat? In this article I review a recent study that answers that question.

This study is interesting for two reasons.

It identifies the characteristics of processed foods that make us want to eat more.

It identifies some minimally processed foods that have the same characteristics and suggests we should choose minimally processed foods wisely. Simply put, knowledge is power. We may want to avoid minimally processed foods that have the same obesity-inducing characteristics as processed foods.

Do Processed Foods Cause Cancer? Previous studies have shown that processed food consumption is associated with a higher risk of obesity, diabetes, and heart disease. Can it get any worse? In this article I review a recent study that shows processed food consumption is associated with an increased risk of several kinds of cancer.

Maintaining Muscle Mass As We Age

As we age, we begin to lose muscle mass, a process called sarcopenia. Unless we actively resist loss of muscle mass it will eventually impact our quality of life and our health.

We can prevent this loss of muscle mass with resistance exercise, adequate protein intake, and adequate intake of the amino acid leucine. Previous studies have shown people over 50 need more of each of these to maintain muscle mass, but the amount they need has been uncertain until now. Three recent studies have given seniors better guidelines for maintaining muscle mass.

Can You Build Muscle In Your 80s? In this article I review a recent study that enrolled a group of octogenarians in a high-intensity exercise program to see if they could gain muscle mass. They were able to increase their muscle mass, but the intensity of the exercise required may surprise you.

Optimizing Protein Intake For Seniors. In this article I review two recent studies that looked at the amount, timing, and kind of protein needed for seniors in their 60s and 70s to maximize gain in muscle mass.

How Much Leucine Do Seniors Need? In this article I review a recent study that determined the amount of leucine seniors in their 70s need to optimize gains in muscle mass and strength.

The Benefits And Risks Of Supplementation

If you listen to Big Pharma or the medical profession, you hear a lot about the “risks” of supplementation and very little about the benefits. In “Health Tips From the Professor” I try to present a more balanced view of supplementation by sharing high-quality studies showing benefit from supplementation and studies that put the supposed risks into perspective.

The Good News About Omega-3s and Stroke. Multiple studies have shown that omega-3 supplementation reduces the risk of ischemic strokes (strokes caused by a blood clot). But it has been widely assumed they might increase the risk of hemorrhagic strokes (strokes caused by bleeding). In this article I review a meta-analysis of 29 clinical studies with 183,000 participants that tested that assumption.

How Much Omega-3s Are Best For Blood Pressure? Multiple studies have shown that omega-3 supplementation can reduce high blood pressure. But the doses used vary widely from one study to the next. In this article I review a meta-analysis of 71 double-blind, placebo-controlled clinical studies that determined the optimal dose of omega-3s for controlling blood pressure.

Omega-3 Supplements Are Safe. As I said above, it has been widely assumed that omega-3 supplementation increases the risk of bleeding and hemorrhagic stroke. In this article I review the definitive study on this topic. More importantly, it reveals which omega-3 supplements might increase bleeding risk and which do not.

Are Calcium Supplements Safe? Big Pharma and the medical profession have been warning us that calcium supplements may increase heart disease risk. In this article I review the definitive study on this topic.

Prenatal Supplements

If you are pregnant or thinking of becoming pregnant, your health professional has likely recommended a prenatal supplement. You probably assume that prenatal supplements provide everything you need for a healthy pregnancy. Unfortunately, recent research has shown that assumption is not correct.

Is Your Prenatal Supplement Adequate? In this article I review a study that should serve as a wakeup call for every expectant mother. It showed that most prenatal supplements were woefully inadequate for a healthy pregnancy.

What Nutrients Are Missing In Prenatal Supplements? In this article I review a study that identified additional nutrients that are missing in most prenatal supplements.

Prenatal Supplements Strike Out Again. In this article I review a study that looked at the diet of pregnant women to determine their needs and compared that to the nutrients found in prenatal supplements. Once again, most prenatal supplements were woefully inadequate. Is it, “Three strikes and you are out”?

Exercise

Walking Your Way To Health. We have been told that walking is good for our health. But how many steps should you take, how fast should you walk, and does it matter whether these steps are part of your daily routine or on long hikes? In this article I review a study that answers all these questions.

Which Exercise Is Best For Reducing Blood Pressure? If you have high blood pressure, you have probably been told to exercise more. But which exercise is best? In this article I review a study that answers that question. And the answer may surprise you.

Did You Know?

If you have been reading “Health Tips From the Professor” for a while, you probably know that I enjoy poking holes in popular myths. Here are two new ones I deflated in past two years.

Is Low Alcohol Consumption Healthy? You have probably heard that low alcohol intake (that proverbial glass of red wine) is good for you. But is that true? In this article I review a recent study that shows that myth was based on faulty interpretation of the data and provides a more nuanced interpretation of the data.

Is HDL Good For Your Heart? You have been told that increasing your HDL levels reduces your risk of heart disease so many times it must be true. But is it? In this article I review HDL metabolism and a recent study to provide a more nuanced interpretation of the relationship between HDL and heart disease risk.

How To Talk With Your Doctor About Cancer

Because of my years in cancer research, I am often asked whether someone should follow their oncologist’s advice and go on a recommended chemotherapy or radiation regimen. Of course, it would be unethical for me to provide that kind of advice.

In this article I tell you the questions to ask your oncologist about the prescribed treatment regimen, so you can make an informed decision. However, I also recommend you only ask these questions if you can handle the answers.

The Bottom Line

I have just touched on a few of my most popular articles above. You may want to scroll through these articles to find ones of interest to you that you might have missed over the last two years. If you don’t see topics that you are looking for, just go to https://chaneyhealth.com/healthtips/ and type the appropriate term in the search box.

In the coming years, you can look for more articles debunking myths, exposing lies and providing balance to the debate about the health topics that affect you directly. As always, I pledge to provide you with scientifically accurate, balanced information that you can trust. I will continue to do my best to present this information in a clear and concise manner so that you can understand it and apply it to your life.

Final Comment: You may wish to share the valuable resources in this article with others. If you do, then copy the link at the top and bottom of this page into your email. If you just forward this email and the recipient unsubscribes, it will unsubscribe you as well.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

_______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years. Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com/lifestylechange/.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Can You Build Muscle in Your 80s?

August 6, 2024 by Dr. Steve Chaney

What Does It Take to Build Muscle in Your 80s?

Author: Dr. Stephen Chaney

As we age it becomes harder to build muscle, so we start to lose muscle mass and strength, a physiological process called sarcopenia. In last week’s issue of “Health Tips From the Professor” I shared studies showing it was possible to slow, and even reverse, age-related loss of muscle mass in our 60’s and 70’s with the correct combination of resistance exercise, protein, and leucine.

But what about those of us in our 80s? Here recent studies have not been as reassuring. The results have been mixed, with some studies suggesting it is impossible to maintain muscle mass in our 80s.

But we know that it is possible for some people to maintain their muscle mass and accomplish incredible physical feats in their 80s. For example, those of you who are my age or older may remember Jack LaLanne, the so-called “Father of the Fitness Movement” who had a popular fitness show on TV from 1953 to 1985. He celebrated his 80^th birthday by swimming one and a half miles in the Long Beach harbor towing 80 rowboats with 80 people in them.

Was Jack LaLanne a “freak of nature” or was it his incredible dedication and focus that allowed him to perform incredible physical feats in his 80’s? After all:

He ate only whole, unprocessed foods. He did not allow processed foods, fast foods, or convenience foods to cross his lips.

He did two hours of high-intensity workouts every day until the day before he died at age 96 in 2011.

More important is the question of what his physical feats mean for us. Does his example hold out hopes for all of us who wish to maintain our strength and vigor until the Lord calls us home? Or did he set a standard too high for mere mortals like us to achieve?

That is essentially the question that today’s study (GN Marzuca-Nassr et al, International Journal of Sports Nutrition and Exercise Metabolism, 34: 11-19, 2024) set out to answer.

The authors postulated that previous studies with subjects in their 80s came up short because they included infirm subjects in their studies and/or the intensity of exercise was too low. This study was designed to overcome those shortcomings.

How Was This Study Done?

The investigators recruited 29 healthy, elderly adults (9 men and 20 women) who were either 65-75 (average age = 68) or over 85 (average age = 87) who were still living in the community rather than being institutionalized for health reasons. The average BMI was 26.4 (moderately overweight) for both groups.

The participants selected for the study had not engaged in any kind of regular resistance training in the previous 6 months. The study excluded individuals with any kind of heart disease, health conditions, or physical limitations that would prevent them from participating in the resistance exercise training program associated with this study.

Participants were asked to fill in a three-day dietary recall at the beginning and end of the study. They were asked not to change their habitual dietary intake or physical activity during the study The diet recall at the end of the study showed compliance with this request. Their dietary intake was calculated based on the average of the two diet recalls.

No significant difference in macronutrient content of the diet was found between groups. For example, the 65-75 group consumed 1.1 g of protein/kg of body weight/day, and the over 85 group consumed 1.2 g of protein/kg of body weight/day.

Both groups were enrolled in a 3-times/week resistance exercise program for 12 weeks. The exercise training program was designed as follows:

Warm up consisted of 5-minutes on a cycle ergometer followed by full range of motion upper limb movements and one warm up set on both leg press and leg extension machines.

This was followed by 4 sets on the leg press and leg extension machines and 2 sets of upper body exercises (chest press, lat pulldown, and horizontal row).

Cool-down consisted of 5 minutes of stretching exercises.

Just prior to the study, the maximum strength on each exercise machine was determined for each participant. The intensity of their workouts was increased from 60% to 80% of that maximum over the 12 weeks of exercise training.

The outcomes of the study were as follows:

Quadriceps (the muscles on the front of the thigh) cross-sectional area was measured at the beginning and end of the study.

Whole body lean mass and appendicular lean mass (The lean mass in legs and arms) were measured at the beginning and end of the study.

The maximum strength for one repetition on each exercise machine was measured at the beginning and end of the study.

The increase in quadriceps cross-sectional area, lean mass, and strength was compared for the 65-75 group and the over 85 group.

Can You Build Muscle In Your 80s?

At the beginning of the study, the over 85 age group scored lower in every category measured in this study. For example:

Quadriceps cross-sectional area was 7% less in the over 85 age group than in the 65-75 age group.

Leg extension strength was 10% less in the over 85 age group than in the 65-75 age group.

This loss of muscle mass and strength is to be expected. Although the over 85 age group was consuming enough protein, they were not exercising on a regular basis. Consequently, they were experiencing sarcopenia, age-related loss of muscle mass.

The results of this 12-week resistance exercise intervention were impressive.

Quadriceps cross-sectional area increased by 10% in the 65-75 age group and by 11% in the over 85 age group. These increases were not statistically different.

- Quadriceps cross sectional area increased for everyone in the study, but the increase varied widely from individual to individual.

- The increase varied from 1% to 18% in the 65-75 age group and from 6% to 21% in the over 85 age group.

Whole body lean muscle mass increased by 2% in both the 65-75 and over 85 age groups.

Appendicular lean muscle mass (lean muscle mass in the arms and legs) also increased by 2% in both groups.

Leg extension strength increased by 38% in the 65-75 age group and by 46% in the over 85 age group.

- Once again, the increase in leg extension strength varied considerably from individual to individual. The increase varied from 5% to 76% in the 65-75 age group and from 26% to 70% in the over 85 age group.

Similar results were seen for leg press, lat pull down, chest press, horizontal row, and grip strength.

The authors concluded, “Prolonged [12 week] resistance exercise training increases muscle mass, strength, and physical performance in the aging population, with no differences between 65-75 and 85+ adults. The skeletal muscle adaptive response to resistance exercise training is preserved even in male and female adults older than 85 years.”

What Does It Take To Build Muscle In Your 80s?

Why did this study show a benefit of resistance exercise for building muscle mass in octogenarians when previous studies have come up short? The authors postulated this was due to differences in the subjects included in the study and the intensity, frequency, and duration of resistance exercise.

This study included only healthy, community dwelling seniors who could engage in a rigorous training program. Some previous studies included institutionalized seniors who may have been less healthy and more frail.

The resistance exercise training used in this study involved multiple sets on exercise machines three times a week at 60-80% of maximum intensity for a total of 12 weeks. Previous studies included 1-2 sets, once or twice a week, at lower intensity, and for a shorter duration.

Much more research needs to be done, but the take-home lessons appear to be:

1) It is possible to increase muscle mass in your 80s with sufficient protein and a sufficiently intense resistance exercise program.

2) Not every 80-year-old adult will be able to increase their muscle mass. At the very least, this and previous studies suggest that frail, institutionalized men and women in their 80s may not be able to increase their muscle mass.

- Whether this is because their health conditions interfere with their muscle’s ability to build muscle, or they are simply unable to perform the high intensity exercises required to build muscle mass in their 80’s is unclear. More research is needed. While everyone in this study increased muscle mass and strength, the increase varied widely from individual to individual (see above).

My guess is that some of the people in the study did not get enough protein in their diet to support an increase in muscle mass at 85 and older. The over 85 group averaged 1.2 gm of protein/kg body weight/day, but their intake ranged from 0.8gm/kg/day to 1.6 gm/kg/day.

However, the difference in gain of muscle mass and strength could have been due to almost anything. Unfortunately, this study was too small to reliably determine what caused the differences in response to the resistance training.

3) It may require a high intensity resistance exercise program to increase muscle mass in your 80s. Unfortunately, there are very few studies like this for people in their 80s. All we know is that this was a high intensity, high frequency, and long duration resistance exercise program, and it worked. Studies with lower intensity exercise programs have not worked. But nobody has done a study comparing the effectiveness of different intensity exercise programs for people in their 80s.

4) There are too few studies on what it takes for people in their 80s and beyond to stay fit and healthy. The authors of this report argued that this information is vital for guiding government programs designed to support an aging population. It is equally important for all of us who want to remain fit and healthy in our 80s and beyond.

What Does This Study Mean For You?

In my previous “Health Tips From the Professor” I have discussed multiple studies looking at sarcopenia or age-related muscle loss.

The bad news is that we start losing muscle mass and strength around age 50, and the rate of decline starts to accelerate in our 60s and beyond. This is a normal part of aging. It affects all of us. And if left unchecked, it can have devastating effects on our quality of life in our golden years.

The good news is that we can slow and even reverse the age-related loss of muscle mass by a combination of adequate intake of protein, adequate intake of the essential amino acid leucine, and resistance exercise. Leucine intake is usually adequate when we rely on animal proteins as our main protein source but may be a concern if we rely primarily on plant proteins. So, let’s take a deeper look at protein and exercise requirements.

We need more protein to build muscle in our golden years than we did in our 30s. If you want more information on the studies supporting that statement, go to https://chaneyhealth.com/healthtips/ and type sarcopenia in the search box. Most experts in this field of study recommend around 1.2 gm of protein/kg of body weight/day rather than the RDA of 0.8 gm of protein/kg of body weight/day for people 65 or older who wish to maintain or increase muscle mass. This study suggests that 1.2 gm/kg/day is also sufficient for people who are 85 and older.

Previous studies have shown that the protein is best utilized to preserve muscle mass when it is spread evenly through the day. That is a concern because many seniors get most of their protein in the evening meal. The article I shared last week showed that adding 20 grams of supplemental protein to the low-protein meals (typically breakfast and/or lunch) was sufficient to balance protein intake and minimize age-related muscle loss.

[Note: To help you with the calculations, 1.2 gm of protein/kg of body weight/day is equal to 0.54 gm of protein/pound of body weight/day. Some quick calculations show that amounts to 78 grams if you weigh 140, 95 grams if you weigh 170, and 112 grams if you weigh 200. Or to simplify, that amounts to 25-30 grams of protein/meal for most people – more if you weigh above 170 pounds.]

2) We need a higher intensity of resistance exercise to build muscle in our golden years than we did in our 30s. Several previous studies have hinted at that possibility. This study shows that a high intensity resistance exercise program is effective at building muscle mass for people 85 and above. Previous studies suggest that lower intensity exercise programs are not effective in this age group.

This is an important finding because it is opposite to the usual recommendations for this age group. In the words of the authors, “At an advanced age, people are generally recommended to partake in low-intensive physical activities. We strongly advocate that resistance exercise should be promoted without restriction to support more active, healthy aging.”

Of course, the caveat is that this study excluded frail, institutionalized adults and people with health or physical limitations that would prevent them from participating in a high-intensity resistance exercise program.

So, here are my recommendations:

Discuss your desire to implement a high intensity resistance exercise program with your health professional. Ask them about any health issues or physical limitations that would affect the exercises you choose.

Ask your health professional to refer you to a physical therapist to design a high-intensity exercise program you can do at home that is appropriate to your health and physical condition. If the referral comes from your health professional, these sessions may be covered by insurance.

If you want to utilize the exercise equipment in a gym, start by having a personal trainer knowledgeable about working with people like you design a workout program for you. My personal preference is to continue working with a personal trainer who challenges me to maximize the intensity of my training while taking into account any temporary physical limitations I may be experiencing.

Finally, I recognize that the exercise program described in this study may be too intense for many of my readers. But I also suspect that none of you want to become so frail you can’t enjoy your golden years. So, do what you can. But do something.

The Bottom Line

Most Americans lose lean muscle mass as they age, a physiological process called sarcopenia. This loss of muscle mass leads to reduced mobility, a tendency to fall (which often leads to debilitating bone fractures) and a lower metabolic rate – which leads to obesity and all the illnesses that go along with obesity.

Fortunately, sarcopenia is not an inevitable consequence of aging. There are 3 things we can do to prevent it.

Optimize resistance exercise training.

Optimize protein intake.

Optimize leucine intake.

Last week I talked about optimizing protein and leucine intake. This week I review an article that compared the effectiveness of a 12-week high intensity resistance exercise program for increasing muscle mass and strength with people in the 65-75 age group with those who were age 85 and above.

The results of this 12-week resistance exercise intervention were impressive.

Quadriceps cross-sectional area increased by 10% in the 65-75 age group and by 11% in the over 85 age group. These increases were not statistically different.

Whole body lean muscle mass increased by 2% in both the 65-75 and over 85 age groups.

Leg extension strength increased by 38% in the 65-75 age group and by 46% in the over 85 age group.

Similar results were seen for leg press, lat pull down, chest press, horizontal row, and grip strength.

“At an advanced age, people are generally recommended to partake in low-intensive physical activities. We strongly advocate that resistance exercise should be promoted without restriction to support more active, healthy aging.”

For more details about the study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

______________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author

Optimizing Protein Intake For Seniors

July 30, 2024 by Dr. Steve Chaney

The Role Of Muscle Protein In Energy Metabolism

Author: Dr. Stephen Chaney

We’ve been told, It’s all downhill after 30.” That may or may not be true depending on the lifestyle choices we make.

But for muscle mass, “It’s all downhill after 50!” Simply put, we start to lose muscle mass at an accelerating pace after 50, a process scientists call sarcopenia.

Sarcopenia should be a major concern for everyone over 50. Loss of muscle mass:

Causes unsteadiness which can lead to falls, bone fractures, and death.

Increases the risk of obesity because muscle burns more calories than fat. That increases our risk of obesity-related diseases such as heart disease, diabetes, some cancers, osteoarthritis, and other inflammatory diseases.

Robs us of the fun activities we would like to enjoy in our golden years.

But sarcopenia is not inevitable. As I have discussed in previous issues of “Health Tips From the Professor”, there are three things we can do to minimize sarcopenia as we age.

Get adequate weight-bearing exercise. In other words, pump iron or use your body weight.

Get adequate protein.

Get adequate amounts of the branched-chain amino acid leucine.

In this article I will focus on the last two, especially the fact that we need more protein and leucine to prevent loss of muscle mass as we age. To help you understand why that is, I am going to share my favorite topic – Metabolism 101 (Once a biochemistry professor, always a biochemistry professor).

Metabolism 101: The Role Of Muscle Protein In Energy Metabolism

Most people associate muscle mass with strength and endurance. Many understand the important role muscle mass plays in burning off excess calories and keeping us slim. But few people understand the important role that muscle protein plays in our everyday energy metabolism.

Let’s start with an overview of metabolism [Note: If you are not interested in this, you can just skip over the bullets and read the take-home message at the bottom of this section.]

We get energy from the carbohydrate, fat, and protein we consume. Excess carbohydrate, fat, and protein in our meals are stored to provide the energy our body needs between meals and during prolonged fasting.

- We have a virtually unlimited ability to store fat, as some of you may have noticed.

- We have a very limited ability to store carbohydrates in the form of glycogen in our liver.

- Our ability to store protein is even more limited, even when protein intake is coupled with exercise. And muscle protein plays other very important functions. It is a precious resource.

- Finally, any carbohydrate and protein beyond our body’s ability to store it is converted to and stored as fat.

In the fed state most of our energy is derived from blood glucose. This is primarily controlled by the hormone insulin. As blood glucose levels fall, we move to the fasting state and start to call on our stored energy sources to keep our body functioning. This process is primarily controlled by a hormone called glucagon.

- In the fasting state most tissues easily switch to using fat as their main energy source, but…

- - Red blood cells and a few other tissues in the body are totally dependent on glucose as an energy source.

- - Initially our brain is totally dependent on glucose as an energy source, and our brains use a lot of energy. [Note: Our brain can switch to ketones as an energy source with prolonged starvation or prolonged carbohydrate restriction, but that’s another story for another day.]

Because our brain and other tissues need glucose in the fasting state, it is important to maintain a constant blood glucose level between meals.

- Initially, blood glucose levels are maintained by calling on the glycogen reserves in the liver.

- But because these reserves are limited, our body starts to break down muscle protein and convert it to glucose as well – even in the normal dinner/sleep/breakfast cycle.

You may have found the explanation above was excessive, but I couldn’t think of a simpler way of helping you understand that in addition to its other important role in the body, muscle protein is also an energy store.

When we eat, we make a deposit to that energy store. Between meals we withdraw from that energy store. When we are young the system works perfectly. Unless we fast for prolonged periods of time, we are always adding enough muscle protein in the fed state to balance out the withdrawals between meals.

But as we age, our ability to build muscle in the fed state becomes less efficient. Withdrawals exceed deposits, and we experience age-related muscle loss (sarcopenia).

What We Know About Preventing Age-Related Muscle Loss

As I said above, there are three things needed to prevent age-related muscle loss:

Adequate resistance exercise.
Adequate amounts of protein.
Adequate amounts of the essential, branched-chain amino acid called leucine.

And, as I said above, I am going to focus on the last two.

In previous issues of “Health Tips From the Professor” I have shared articles showing that the amount of both protein and leucine needed to maximize the gain in muscle mass following a meal or a workout increase as we age. For example:

For someone in their 30s, 15-20 grams of protein with 1.7 grams of leucine per meal is optimal.

But someone in their 60’s and 70s needs 25-30 grams of protein and 2.5-2.7 grams of leucine per meal to achieve the same effect.

Most of these studies have been done with men, but a recent study showed the results are identical with post-menopausal women.

However, previous studies have not addressed the role of protein supplementation in achieving adequate protein intake or what kind of protein supplements were best. The studies I will discuss today were designed to answer these questions.

How Were These Studies Done?

Study #1: As I said above, previous studies have suggested that 25-30 grams of protein per meal is optimal for preventing age-related loss of muscle mass in seniors. However, many seniors get most of their protein in their evening meal. On average, seniors consume 8-15 grams of protein at breakfast, 15-20 grams of protein at lunch, and 30-40 grams of protein at dinner.

This study (C Norton et al, The Journal of Nutrition, 146: 65-67, 2016) was designed to ask whether optimizing protein intake at each meal by adding a protein supplement at breakfast and lunch would increase lean muscle mass in seniors over a 24 week period.

The investigators recruited 60 adults, aged 50-70 (average age = 61) from the city of Limerick, Ireland. The participants were 73% women and had an average BMI of 25.8 (slightly overweight).

The participants were randomly assigned to receive either a milk-based supplement or an isocaloric, non-protein containing, maltrodextrin control. The protein supplement provided 15 grams of protein. The participants were instructed not to change any other aspect of their diet or activity level.

The protein supplement and placebo were provided in identical sachets and the participants were told to mix them with water and consume them with breakfast and lunch. The protein supplement and placebo looked and tasted identical, so the subjects did not know which group they were in. Compliance was assessed by collecting the used sachets at the end of the study.

The participants completed 4-day diet recalls under the supervision of a dietitian before and during the study. Lean muscle mass was determined prior to and at the end of the 24-week study.

Study #2: This study (J McKendry et al, The American Journal Of Clinical Nutrition, doi: 10.1016/j.ajcnut.2024.05.009) was designed to determine whether the ability to stimulate muscle protein synthesis depended on the type of supplemental protein.

This study was built on the results of the first study. Specifically, the investigators compared the effect on muscle protein synthesis of adding 25 grams of whey, pea, or collagen protein to the breakfast and lunch meals.

The investigators enrolled 31 healthy, older (average age = 72) subjects from the Hamilton, Ontario area. Subjects were excluded from the study if:

They had a medical condition or were taking any medication that might influence the results.
They used tobacco or tobacco related products.
They consumed a vegan or vegetarian diet
They used a walking device or were inactive for any reason.

The participants were placed on a standardized diet consisting of prepackaged meals (breakfast, lunch, and dinner) and a mix of fruits, vegetables, snacks, and drinks. They were instructed to only eat the foods provided to them and to maintain their normal activity levels.

The diet was designed to provide the RDA for protein (0.8 gram of protein/kilogram of body weight) and to mimic the habitual dietary patterns of seniors in the United States and Canada.

Around 55% carbohydrate, 30% fat, and 15% protein.
Uneven distribution of protein through the day (19% at breakfast, 26% at lunch, and 55% at dinner).

After one week on the control diet, participants were randomly assigned to receive 25-gram protein supplements of either whey, pea, or collagen protein and instructed to add them to their standardized diet for breakfast and lunch (total protein intake was increased by 50 grams/day). They followed this regimen for 7 days.

On day one and 7 of the control phase and on day 7 of the intervention phase (when the participants were consuming additional protein) muscle biopsies were obtained 90 minutes after breakfast for determination of the effect of the meal on muscle protein synthesis.

[Note: The participants were consuming a protein supplement containing an additional 25 grams of protein at both breakfast and lunch. But the effect of this additional protein on protein synthesis was only determined after the breakfast meal.]

Optimizing Protein Content For Seniors

Each of the studies provided important insights for anyone wanting to minimize age-related muscle loss.

Study #1: The effect of the whey protein supplement for breakfast and lunch on protein intake was as follows:

Protein Intake In Grams
Meal	Baseline	Plus Protein Supplement
Breakfast	15	27
Lunch	22	34
Dinner	38	38
Snacks	8	7
Total	83	106

[Note: The amount of additional protein from diet and supplementation averaged around 12 grams/meal instead of 15 grams in the supplemental protein provided. The investigators did not address this, but I suspect the participants may have cut back on their regular food intake because the protein supplement reduced their appetite.]

The results were clear cut:

Protein supplementation at breakfast and lunch resulted in a 1.3-pound gain in lean body mass over 24 weeks compared to the control group using an isocaloric, non-protein containing maltodextrin supplement.

The authors concluded, “Protein supplementation at breakfast and lunch for 24 weeks in healthy older adults resulted in a positive (1.3 pound) difference in lean muscle mass compared with an isoenergetic, nonnitrogenous maltodextrin control. These observations suggest that an optimized and balanced distribution of meal protein intakes could be beneficial in the preservation of lean tissue mass in the elderly.”

I would add two things:

This study did not show that these protein levels were optimal. It only showed that using a protein supplement to increase protein intake at breakfast and lunch was beneficial for seniors consuming most of their protein at dinner.

This study also did not show that a total intake of 106 grams of protein in the supplemented group was necessary for maintaining lean muscle mass.

If the 83 grams of protein in the control group were evenly divided between breakfast, lunch, and dinner it would have come to almost 28 grams of protein per meal. That would fall within the 25-30 grams of protein per meal that most experts feel is sufficient to help seniors prevent age-related loss of lean muscle mass.

Study #2: The effect of the three protein supplements at breakfast and lunch on protein intake was as follows:

Protein Intake In Grams
Protein Source	Control Phase	Supplemental Phase
Collagen	70	112
Whey Protein	68	108
Pea Protein	64	104

[Note: The amount of additional protein from the control diet plus supplementation averaged around 40 grams/meal instead of 50 grams in the supplemental protein provided. This means that study participants were actually consuming an extra 20 grams of protein at breakfast and lunch.]

Again, the results were clear cut:

Adding ~20 grams of either whey or pea protein to a relatively low-protein (15 grams) breakfast increased muscle protein synthesis by ~9%.

Adding ~20 grams of collagen to the same low-protein breakfast had no effect on muscle protein synthesis.

The authors concluded, “We discovered that the RDA [for protein] was insufficient to support higher rates of MPS [muscle protein synthesis] in older adults. Manipulating dietary protein to increase daily consumption of higher quality – whey and pea but not collagen – proteins by targeting the lowest protein-containing meals offers a viable strategy to enhance…MPS in older adults.”

“Consuming protein much closer to expert group consensus recommendations [1.2 gm/kg instead of the current 0.8 gm/kg for adults over 50] may help to increase…MPS with advancing age and extend health-span – compressing the years of disease and disability commonly experienced by older individuals closer to the end of life.”

My comments are:

You may recall from the previous discussion that age-related muscle loss occurs because muscle protein synthesis (MPS) becomes less efficient as we age.

- Therefore, an increase in muscle protein synthesis following each meal will lead to an increase in muscle mass over time, such as was seen in the first study.

In our 60’s and beyond we require higher amounts of both protein and leucine to maximize muscle protein synthesis.

The collagen supplement used in this study provided enough supplemental protein. But it probably was ineffective because it only provided 0.86 grams of leucine.

- The amount of leucine in the control diet was not specified, but with only 15 grams of protein for breakfast there was probably enough leucine to make up for the lack of leucine in the collagen supplement.

In contrast the whey and pea supplements provided 2.7 and 2.1 grams of leucine, respectively. When added to the leucine in the control diet, this would be more than enough to drive muscle protein synthesis.

- Not every pea protein supplement may be as effective as the one used in this study. When I looked it up, it was described as an “enriched pea protein designed as a soy and milk alternative.” The manufacturer did not say how it was “enriched”, but I suspect it was enriched by adding extra leucine.

Finally, this study does not show that seniors need to consume more than 100 grams of protein per day. It simply shows that adding an extra 20 grams of supplemental protein to a low-protein meal can help maximize muscle protein synthesis and minimize age-related muscle loss.

What Do These Studies Mean For You?

Don’t Leave Out Resistant Exercise. These studies were focused on the timing and quality of protein. But don’t forget that adequate protein and leucine are only two of the requirements for preventing age-related muscle loss. The third, and arguably the most important, is resistance exercise.

Aim for at least three 30-minute resistance exercise sessions per week. If you have physical limitations consult with your health professional about the type, duration, and intensity of resistance exercise that is right for you.

Forget What You Have Been Told About Protein. You have been told that American consume too much protein. That’s probably true for the average couch potato. But it is not true for seniors. The average American does consume too much of the wrong kind of protein, but that’s another story for another day.

You have been told that the average woman only needs 46 grams of protein per day and the average man needs only 56 grams of protein per day. That’s based on the RDA of 0.8 gm/kg (0.36 gm/pound) and an average weight of 127 pounds for women and 155 pounds for men.

We haven’t weighed that since the 50’s. Today the average woman weighs 170 pounds, and the average man weighs 201 pounds. That means protein intake should be at least 61 gm/day for women and 72 gm/day for men.

But that’s only if you are in your twenties or thirties. The consensus among those who study protein needs in seniors is that the RDA should be 1.2 gm/kg (0.54 gm/pound) for adults over 50. That’s 91 gram/day and 108 grams/day, respectively, for average weight women and men.

With that perspective, it is easy to understand the recommendation that seniors get 25-30 grams of protein and 2.5-2.7 grams of leucine per meal. That’s 75-90 grams of protein and 7.5-8.1 grams of leucine per day. But that is probably not what you are hearing from your doctor.

Why Is Supplemental Protein Important? It’s easy to say that seniors should get 25-30 grams of protein per meal, but that’s not the way most seniors eat.

When I was a child growing up in Alabama the standard breakfast was eggs, ham, grits with ham gravy and biscuits. I’m not saying that was a healthy breakfast, but it was the standard breakfast where I lived at the time. And it provided plenty of protein.

In today’s world most seniors have been told to avoid eggs and red meat. Breakfasts are more likely to be some type of cereal with a fruit garnish and perhaps some toast. That’s a much healthier breakfast, but it’s a low-protein breakfast. That’s why most seniors only get 8-15 grams of protein at breakfast time.

I won’t go into lunches, but similar transformations have taken place at lunch time.

So, if you want to avoid age-related muscle loss you have two choices:

Completely change your diet and incorporate more healthy protein foods into your breakfast and lunch menus or…

Add a protein supplement to your low-protein meals. The second study suggests that 20 grams of supplemental protein will be sufficient to transform a low-protein meal into one that will support muscle protein synthesis and minimize age-related muscle loss.

Why Is Protein Quality Important? The second study shows that having enough protein is not sufficient to stimulate muscle protein synthesis. It must be high quality protein.

The authors of the study suggested that collagen did not stimulate muscle protein synthesis due to its low leucine content.

And, as I mentioned earlier, the pea protein used in the study was “enriched” so it could be used as a “whey or soy alternate”, and the “enrichment” probably included adding extra leucine.

So, if you are planning to use a plant protein supplement with your low-protein meal(s), I would recommend choosing one with added leucine.

How Much Protein Is Too Much? The ability of a protein meal and/or supplement to stimulate muscle protein synthesis begins to plateau at around 30 grams of protein, so there is little advantage to protein intakes above 30 grams at one time. And as I said above, excess protein is stored as fat.

What About An After-Workout Supplement? Previous studies have shown that the numbers are about the same for after-workout supplements.

For someone in their 30s, 15-25 grams of protein with 1.7 grams of leucine per meal is enough to maximize muscle gain after a workout.

But someone in their 60s or 70s needs 25-30 grams of protein and 2.5-2.7 grams of leucine per meal to maximize muscle gain.

After-workout supplements can also be designed to optimize the insulin response, but that is another story for another day.

One Final Pearl

At the very beginning of this article, I told you that the breakdown of muscle protein to keep blood sugar levels constant during fasting and starvation was driven by a hormone called glucagon.

And the active ingredient in the latest weight loss drugs like Wegovy, Ozempic, and Trulicity is GLP-1, which stands for glucagon-like peptide-1.

So, it should be no surprise that those drugs cause loss of muscle mass. That’s a side effect you probably haven’t been told about.

The Bottom Line

It’s all downhill after age 50! That’s when we start to experience age-related muscle loss, something called sarcopenia.

Age-related muscle loss can be prevented with resistance exercise, adequate protein, and adequate leucine. And the amount of both protein and leucine we need to prevent muscle loss increases as we age.

Previous studies have defined the amount of protein and leucine we need to prevent muscle loss in our 60s and 70s. The studies described in today’s health tip show the benefit of adding a protein supplement to our low-protein meals and the importance of a high-quality protein supplement for minimizing age-related muscle loss.

For more information on these studies and what they mean for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

_____________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author

Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

How Much Leucine Do Seniors Need?

June 4, 2024 by Dr. Steve Chaney

Where Can Seniors Find The Protein And Leucine They Need?

Author: Dr. Stephen Chaney

Most Americans lose lean muscle mass as they age, a physiological process called sarcopenia. There are three factors that influence the rate at which we lose muscle mass as we age:

Our physiology changes. Our bodies break down our protein stores more rapidly and we have a harder time utilizing the protein in our diet to replenish those protein stores.

We become less active. In some cases, this reflects physical disabilities, but all too often it is because we are not giving weight-bearing exercises the proper priority in our busy lives.

Our diets have become inadequate. A major driver of this phenomenon is loss of appetite which results in decreased caloric intake. However, physical disability, isolation, and insufficient income also contribute.

Some of you may be saying “So what? I wasn’t planning on being a champion weightlifter in my golden years.” The “So what” is that loss of muscle mass leads to reduced mobility, a tendency to fall (which often leads to debilitating bone fractures) and a lower metabolic rate – which leads to obesity and all the illnesses that go along with obesity.

Fortunately, sarcopenia is not an inevitable consequence of aging. There are things that we can do to prevent it. The most important thing that we can do to prevent muscle loss as we age is to exercise – and I’m talking about resistance (weight) training, not just aerobic exercise.

But we also need to optimize our protein intake and our leucine intake. Protein is important because our muscle fibers are made of protein.

Leucine is an essential amino acid. It is important because it stimulates the muscle’s ability to make new protein. Leucine and insulin act synergistically to stimulate muscle protein synthesis after exercise.

In a previous issue of “Health Tips From the Professor” I shared studies showing that the amount of protein and leucine we need to prevent muscle loss increases as we get older. The study (ME Lixandrao et al, Nutrients, Volume 13, Issue 10, 10.3390/nu13103536) I am reviewing today is an update on the leucine needs for seniors.

How Was This Study Done?

The investigators recruited 67 healthy, elderly, overweight adults (34 men and 33 women; average age = 69.7; average BMI = 26.4) in Basel, Switzerland for the study. The participants selected for the study were not engaged in any kind of regular resistance or aerobic training in the previous 6 months.

Participants were asked to fill in three 24-hour dietary recalls (2 on non-consecutive weekdays and one on a weekend day). A trained nutritionist gave instructions on how to perform the dietary recalls. After the dietary recalls were completed, the nutritionists used pictures of foods included in each participant’s diet recall to confirm the accuracy of their portion size estimates. This diet information was used to calculate habitual daily protein and leucine intake.

The investigators used magnetic resonance imaging (MRI) to measure quadriceps cross-sectional area – a measure of muscle mass. They also used performance on a leg extension machine to measure unilateral maximum dynamic muscle strength – a measure of muscle strength.

The study correlated leucine intake with both muscle mass and muscle strength. The data were corrected for sex, age, and total protein intake normalized to body weight.

How Much Leucine Do Seniors Need?

There was a biphasic correlation between leucine intake and both muscle mass and muscle strength in this population.

There was a positive association between leucine intake and muscle mass up to 7.6 gm/day. After that a plateau was reached. Additional leucine had no effect on muscle mass.

There was a positive association between leucine intake and muscle strength up to 8.0 gm/day. After that a plateau was reached. Additional leucine had no effect on muscle strength.

These associations held true even after correcting for total protein intake. This is an important control because none of these participants were taking a leucine supplement, so those consuming more leucine were also consuming more protein.

The authors concluded, “We demonstrated that total daily leucine intake is associated with muscle mass and strength in healthy older individuals, and this association remains after correcting for multiple factors, including overall protein intake. Furthermore, our…analysis revealed…a potential threshold for habitual leucine intake, which may guide future research on the effect of chronic leucine intake in age-related muscle loss [sarcopenia].

Randomized control trials should test the utility of additional leucine to counteract frailty in the elderly.”

What Does This Study Mean For You?

Let me start by saying that leucine is not a “magic bullet” that will prevent sarcopenia (age-related loss of muscle mass) by itself. Three things are essential for preventing sarcopenia:

Resistance (weight bearing) exercise. You should aim for at least 3 days/week of moderate intensity weight bearing exercise a week.

If you have physical limitations, consult with your health professional before beginning an exercise program. And if you have not done weight bearing exercise before, it is best to start with instruction from a personal trainer to be sure you are using appropriate weights and appropriate form.

[Note: The participants in this study had not done weight bearing exercise for 6 months prior to the study and did not exercise during the study.]

Adequate protein. I have discussed this in a previous issue of “Health Tips From the Professor”. If you are in your 30’s, 15-20 grams of protein per meal will do. But if you are in your 60’s and above, it’s better to aim for 25-30 grams of protein per meal.

[Note: On average the men in this study were consuming 87 grams of protein per day. That’s 29 grams per meal. The women in this study averaged 67 grams of protein per day or 22 grams per meal. So, most of the participants in this study were consuming adequate protein.]

Adequate leucine. This study showed that the benefits of leucine plateaued at around 7.6-8.0 grams per day or 2.5 to 2.7 grams per meal for non-exercising adults in their 60’s and 70’s.

This is in close agreement with studies showing that 25-30 grams of protein and 2.7 grams of leucine were optimal for seniors in this age range following weight bearing exercise.

[Note: This study only determined the optimal intake of leucine. Remember for maximal effectiveness at reducing age-related muscle mass (sarcopenia) you need optimal protein, optimal leucine, and an optimal resistance (weight bearing) exercise program.]

Where Can Seniors Find The Protein And Leucine They Need?

For most Americans this is not too difficult as the table above shows. If you look at single foods, chicken and soybeans are the best sources of both protein and leucine. Other meats and other beans & legumes are also good choices.

I included things like eggs, dairy foods, broccoli, and spinach as a reminder that you don’t need to get all your protein and leucine from a single food source. Other whole foods included in your meal can contribute to your protein and leucine totals.

This table also shows that you don’t need to be a carnivore to get the protein and leucine you need. However, if you avoid most meats or are a pure vegan, you will need to plan your diet a bit more carefully.

Finally, if you are looking to optimize your workouts with an after-workout plant-based protein shake, soy protein would be your best choice. If you chose plant protein, you should look for high-quality protein shakes with added leucine to make sure you meet both your protein and leucine goals.

The Bottom Line

Most Americans lose lean muscle mass as we age, a physiological process called sarcopenia. This loss of muscle mass leads to reduced mobility, a tendency to fall (which often leads to debilitating bone fractures) and a lower metabolic rate – which leads to obesity and all the illnesses that go along with obesity.

Fortunately, sarcopenia is not an inevitable consequence of aging. There are 3 things we can do to prevent it.

Exercise – and I’m talking about resistance (weight) training, not just aerobic exercise. This is the most important thing that we can do to prevent muscle loss as we age.

Optimize our protein intake.

Optimize our leucine intake.

Previous studies have determined the optimal protein intake for preventing sarcopenia. The study I describe above determined the optimal leucine intake.

For more details about the study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

______________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

______________________________________________________________________

About The Author

How Much Protein Do Post-Menopausal Women Need?

March 19, 2024 by Dr. Steve Chaney

Does The Design Of The Protein Supplement Matter?

Author: Dr. Stephen Chaney

You’ve probably heard the saying, “It’s all downhill after 30”. That’s a particularly gloomy way of looking at it, but Father Time does take a toll on our body. I’m going to focus on age-related loss of muscle mass today, a physiological process called sarcopenia.

There are three factors that influence the rate at which we lose muscle mass as we age:

1) Our physiology changes. Our bodies break down our protein stores more rapidly and we have a harder time utilizing the protein in our diet to replenish those protein stores.

2) We become less active. In some cases, this reflects physical disabilities, but all too often it is because we are not giving weight-bearing exercises the proper priority in our busy lives.

3) Our diets become inadequate. The major driver of this phenomenon is loss of appetite which results in decreased caloric intake. However, physical disability, isolation, and insufficient income also contribute.

Sarcopenia in turn results in:

Loss of muscle strength. Even the simple act of picking up a grandchild or a bag of groceries can become problematic.

Increased risk of falls and fractures.

Lower quality of life.

Obviously, sarcopenia is a major health issue for those of us in our golden years. If you are younger, it is a concern for your parents or grandparents. Sarcopenia is a health issue that affects everyone.

But what can be done to prevent sarcopenia? We can’t change our physiology, but we can change our activity level and our diet. Weight-bearing exercise tugs on our muscle fibers. That stimulates those fibers to incorporate protein into new muscle cells. It is no wonder that weight-bearing exercise is recommended for preventing sarcopenia.

What about diet? Are older adults getting enough protein in their diet to benefit from weight-bearing exercise? I have shared studies showing that older adults need more protein and higher levels of the amino acid leucine to benefit from their workouts.

But those studies were done with men. There have been no studies comparing younger and older women until now.

In this article, I discuss a recent study (CF McKenna et al, Journal of Applied Physiology, Feb 22, 2024 doi.org/10.1152/applphysiol.00886.2023) that asks how much protein is needed to stimulate muscle protein synthesis following a workout in post-menopausal women and compares it to the protein needs of younger women.

How Was The Study Done?

The investigators enrolled 16 post-menopausal women who were part of a much larger study investigating exercise and nutritional regimens that preserve and/or enhance muscle mass in women.

The women in this study were on average 60 years old with a BMI of 26 (overweight). They had no heart disease, dietary restrictions, and did not take any supplements that could affect protein metabolism.

They were compared to a cohort of pre-menopausal women (average age = 24, BMI = 25 (borderline overweight)) recruited from the same large study. The experimental protocol was the same for the pre-menopausal and post-menopausal cohorts.

The study design was what is called a parallel-group design. Simply put, one leg was exercised using a leg extension machine, while the other leg was rested. The rested leg served as the control for each participant in the study.

Participants were tested ahead of time to determine the “one-repetition maximum” (1RM) weight for complete leg extension for each participant.

On the day of the experiment participants arrived in the laboratory after an overnight fast. One iv line was inserted, and a labeled amino acid was infused into the bloodstream, so the investigators could measure new protein synthesis at any time during the 4-hour experiment. Another iv line was inserted, so the investigators could withdraw blood samples.

At the beginning of the experiment, each participant was given either a whey protein drink (whey protein isolate fortified with vitamins C, B1, B2, B3, folate, B6, and B12 and minerals calcium, magnesium, iron, zinc, and potassium) or water. They then performed a bout of single-leg extensions starting with a warm-up of 2 sets of repetitions at 30% 1RM followed by 3 sets of 12 repetitions at 65% 1RM with 90 seconds of rest provided between sets.

Immediately following exercise, muscle biopsies were collected from both legs (t=0). Muscles biopsies were also collected at 120 and 240 minutes after exercise. Blood samples were collected continually during the experiment.

Muscle tissue was isolated from each biopsy, and something called myofibrillar protein synthesis (protein synthesis in muscle fibers) was determined based on the amount of labeled amino acid incorporated into muscle protein. The amount of protein synthesis due to exercise was determined by subtracting the incorporation of labeled amino acid in muscle fibers in the rested leg from that in the exercised leg.

What Is Leucine?

Leucine is an essential amino acid. It is present in all dietary proteins, but it is more abundant in whey and soy protein than in some vegetable proteins.

Leucine is also one of three branched-chain amino acids (valine and isoleucine are the other two). If you are familiar with the weightlifting and body-building world, you will know that branched-chain amino acids are thought to be important for muscle gain. However:

It turns out that leucine is the only branched chain amino acid that stimulates muscle protein synthesis (Am J Physiol Endocrinol Metab 291: E381-E387, 2006). And protein is what gives muscles their strength and their bulk.

The other branched chain amino acids appear to play a supporting role in the quantities that occur naturally in most proteins. And adding extra valine and isoleucine to a protein supplement appears to reduce the effectiveness of leucine at stimulating muscle gain (Am J Physiol Endocrinol Metab 291: E381-E387, 2006).

What Have Previous Studies Shown?

With respect the amount of protein needed to optimize muscle gain after workouts, previous studies have shown that:

The optimal protein intake for maximizing muscle gain post workout is 15-20 gm for young men (Katsanos et al, Am J Clin Nutr 82: 1065-1073, 2005; Moore et al, Am J Clin Nutr, 89: 161-168, 2009) and 20-25 gm for older men (Symons et al, Am J Clin Nutr 86: 451-456, 2007).

More protein isn’t necessarily better. The effect of protein intake on post workout muscle gain maxes out at around 25 gm for young men and 30 gm for older men (Symons et al, J Am Diet Assoc 109: 1582-1586, 2009).

Whey protein is the best choice for enhancing muscle gain immediately after a workout. Other protein sources (soy, casein, chicken) are better choices for sustaining muscle gain over the next few hours.

A previous study by the authors of the present study showed that 15 gm of whey protein was sufficient to stimulate muscle protein synthesis in young women (average age 20). Thus, young women and young men both appear to benefit from 15 gm of protein after a workout.

How Much Protein Do Post-Menopausal Women Need?

This is a complex study, so let’s just start with the big takeaway from the study:

The same whey protein supplement that increased muscle mass in younger women failed to stimulate “cumulative muscle protein synthesis” [net increase in muscle mass] in post-menopausal women. (This was measured by determining net accumulation of labeled amino acids into the muscle fibers of the exercised leg compared to the rested leg.)

With that out of the way, we can focus on some less important findings:

There was a short-term (0-2h) transient increase in muscle protein synthesis following exercise with and without the whey protein supplement, but the result was not cumulative. In other words, the transient protein synthesis did not result in an increase in muscle mass.

There was a long-term (2-4h) transient increase in muscle protein synthesis following exercise for the group taking the whey protein supplement, but, again, the result was not cumulative. It did not result in a net increase in muscle mass.

In the group taking the whey protein supplement there was a transient increase in both insulin and leucine in the blood between 2 and 4 hours. Either or both could have driven the transient increase in protein synthesis observed during that same times.

In the words of the authors, “Ingestion of 15 gm whey protein failed to stimulate [net] myofibrillar (muscle) protein synthesis in post-menopausal women. While resistance exercise with and without feeding stimulate late (2-4 h) and early (0-2h) increases in myofibrillar protein synthesis, further exercise and nutritional manipulations may be necessary to robustly stimulate the skeletal muscle adaptive response to exercise.”

They went on to say that increased exercise intensity and/or increased protein intake may be necessary for post-menopausal women to maintain or increase muscle mass.

What Does This Study Mean For Post-Menopausal Women?

I should start by acknowledging that this was a small study, as are most studies in this field of research. In part this reflects the expense of these experiments and the lack of major government support. But it also reflects the difficulty in recruiting subjects for this kind of experiment. They are hooked up to two iv’s for over four hours and have three muscle biopsies removed from each leg during that time. That’s a pretty invasive experimental protocol.

With this limitation in mind, the biggest takeaway from this study is that post-menopausal women need more protein to build muscle mass than younger women. Young women, just like young men, can build muscle mass with as little as 15 gm of protein post-workout.

Unfortunately, this study did not determine how much protein post-menopausal women need to build muscle mass post-workout. And that is a critical question, because women typically have less muscle mass than men when sarcopenia starts to set in. Resistance (weight-bearing) exercise and adequate protein intake are key to preventing the debilitating effects of sarcopenia in post-menopausal women.

In their conclusion, the authors said that “…further exercise and nutritional manipulations may be necessary [to optimize the post-workout gain in muscle mass for post-menopausal women].”

From an exercise standpoint, the authors speculated that higher intensity exercise may be needed to increase muscle mass in post-menopausal women. However, the exercise protocol they used was based on public health recommendations for resistance training for older adults. A more rigorous exercise protocol might not be suitable for many post-menopausal women.

From a nutritional standpoint, they noted that a previous study had shown that 35 gm of protein post-workout was sufficient to build muscle mass in post-menopausal women. However, they considered 35 gm of protein to be a dangerously high intake for a single serving of protein for post-menopausal women. I concur.

In summary, we know that 15 gm of protein post-workout is too little for postmenopausal women, and while 35 gm of protein is sufficient, it is probably too much. Until further studies are performed in post-menopausal women, I would recommend the 20-25 gm of protein shown to support post-workout muscle gain in older men.

But it is not just the amount of protein that is important. The design of the protein supplement also matters.

Does The Design Of The Protein Supplement Matter?

While the amount of protein in a post-workout supplement is important, the design of the protein supplement also matters. While there are lots of crazy claims on the internet, there are two natural ways to maximize the effect of a protein supplement on muscle mass. Insulin and the amino acid leucine both drive muscle protein synthesis and help maximize post-workout muscle gain.

Recent research has shown that 2-3 gm of leucine (2 gm for young men; 3 gm for older men) is sufficient to maximize post workout muscle gain if protein levels are adequate (Am J Physiol Endocrinol Metab 291: E381-E387, 2006). We don’t know the corresponding leucine requirements for women, so we will need to assume they are similar.

- A 15-gram serving of whey protein isolate only provides 1.4 gm of leucine, far below what is likely to be needed to drive post-workout muscle gain in post-menopausal women.

- If you are a man over 50 or a post-menopausal woman, you should look for a post-workout protein supplement containing added leucine. And even younger adults will get “more bang for your buck” by choosing protein supplements with added leucine.

The insulin response is maximized when the carbohydrate to protein ratio is around 2.5 to 1. The manuscript did not list carbohydrates among the ingredients used in the whey protein supplement used in this study. But if it is like many whey protein supplements nowadays, it probably contained little or no carbohydrate.

- Although less popular in today’s low carbohydrate world, post-workout supplements with a high carbohydrate to protein ratio are also effective in maximizing post-workout muscle gain.

The Bottom Line

Sarcopenia (age-related muscle loss) is a major concern for older Americans. Sarcopenia can result in:

Loss of muscle strength. Even the simple act of picking up a grandchild or a bag of groceries can become problematic.

Increased risk of falls and fractures.

Lower quality of life.

Sarcopenia can be prevented by a combination of resistance exercise and adequate amounts of protein following the workout.

We know that older men require more protein than young men in a post-workout supplement designed to help them maximize the muscle gain associated with resistance exercise. But similar experiments had not been performed with women until now.

In the article above I share a study that shows that post-menopausal women need more protein than young women in a post-workout supplement. But the study did not determine how much protein they need.

I also discuss the amount of protein post-menopausal women likely need in a post-workout supplement, and how that protein supplement could be designed to maximize muscle gain and prevent sarcopenia.

For more information on this study and my recommendations read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

______________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_______________________________________________________________________

About The Author

What Kind Of Protein Is Best For Strength?

February 13, 2024 by Dr. Steve Chaney

What Kind Of Protein Is Best For You?

Author: Dr. Stephen Chaney

Every bodybuilder “knows” that whey is the best protein for building strong muscles. After all, it:

Is absorbed more rapidly than some other proteins.
Contains all nine essential amino acids.
Is naturally rich in leucine, a branched chain amino acid that stimulates increased muscle mass.

However, as someone who is not a vegan but who follows the vegan literature, I frequently come across testimonials from bodybuilders and elite athletes who say they get all the strength and muscle mass they need from plant proteins.

I’ve always assumed they must have dietitians designing the perfect plant protein diet for them. But a recent study surprised me. It challenged that assumption.

Before I talk about this study, let me change our focus. Most of us will never be bodybuilders or elite athletes, but all of us face a common challenge. We all tend to lose muscle mass as we age, something referred to as sarcopenia. I have discussed this in a previous issue of “Health Tips From the Professor”.

Simply put, sarcopenia results in:

Loss of muscle strength. Even the simple act of picking up a grandchild or a bag of groceries can become problematic.
Increased risk of falls and fractures.
Lower quality of life.

Sarcopenia is a major health issue for those of us in our golden years. If you are younger, it is a concern for your parents or grandparents. Sarcopenia is a health issue that affects everyone.

In my previous article I discussed the role of adequate protein intake and exercise in preventing age-related sarcopenia. But I did not discuss what kind of protein was best for preventing muscle loss, and the frailty that comes with it, as we age.

The article (EA Struijk et al, Journal of Cachexia, Sarcopenia and Muscle, 13: 1752-1761, 2022) I will discuss today suggests that plant protein is best for preventing frailty in women as they age. It’s a surprising conclusion, so join me as I evaluate this study.

How Was This Study Done?

The data for this study came from the Nurses Health Study which started in 1976 with 121,700 women nurses and is still ongoing. This study followed 85, 871 female nurses for an average of 22 years starting when they were 60.

Food frequency questionnaires were administered to the participants in the study every four years starting in 1980. The questionnaires were used to calculate:

Total calories consumed.
Percent of calories from protein, carbohydrate, and fat.
Percent of calories from different kinds of protein.
The overall quality of the diet.
Saturated fat, polyunsaturated fat, cholesterol, and alcohol intake.

For this study the investigators used the cumulative average values from all questionnaires completed by participants in the study from age 60 until the onset of frailty.

Frailty was assessed every four years starting in 1992 using something called the FRAIL scale. The FRAIL scale defines frailty based on five self-reported criteria: fatigue, low strength, reduced aerobic capacity, having 5 or more chronic illnesses, and recent significant unintentional weight loss.

It is important to note that strength is only one of the five criteria used to identify frailty, although decreased muscle mass can contribute to lack of energy and reduced aerobic activity.

It is also worth pointing out that multiple studies have shown that primarily plant-based diets are associated with a decrease in chronic diseases.

I will come back to both of these points when I discuss the results of this study.

What Kind Of Protein Is Best For Strength?

I will start with the “big picture” results from this study and then cover some of the important details.

Average intake of:

Total protein was 18.3% of calories consumed.
Animal protein was 13.3% of calories consumed.
Plant protein was 5.0% of calories consumed.
Dairy protein was 3.8% of calories consumed.

When protein intake was divided into quintiles (5 equal parts) and women consuming the most protein were compared to those consuming the least protein for an average of 22 years:

Those consuming the most total protein had a 7% increased risk of developing frailty.

Those consuming the most animal protein had a 7% increased risk of developing frailty. (It is perhaps not surprising that the results were essentially the same for total and animal protein since animal protein was 73% of the total protein consumed by women in this study.)

Those consuming the most plant protein had a 14% decreased risk of developing frailty.

Consumption of dairy protein did not affect frailty.

Substituting as little as 5% of calories of plant protein for:

Dairy protein decreased the risk of developing frailty by 32%.

Animal protein decreased the risk of developing frailty by 38%.

Non-dairy animal protein (meat, fish, and eggs) decreased the risk of developing frailty by 42%.

In addition, substituting as little as 5% of calories of dairy protein for non-dairy animal protein decreased the risk of developing frailty by 14%.

But, as I said above, the frailty scale used in this study included the criteria of developing 5 or more chronic illnesses, and long-term consumption of plant protein is known to reduce the risk of developing chronic illnesses. So, it is important to break the study down into its component parts. When that was done the statistically significant results were:

Those consuming the most total protein had a 7% increased risk of low strength and a 25% increased risk of developing 5 or more chronic diseases.

Those consuming the most animal protein had a 9% increased risk of low strength and a 35% increased risk of developing 5 or more chronic diseases.

Those consuming the most plant protein had an 18% decreased risk of low strength. (It is interesting to note that plant protein consumption did not have a statistically significant effect on the development of chronic diseases in this study. That suggests that the “protective” effect of plant protein may simply be due to the absence of animal protein from the diet.)

Consumption of dairy protein did not affect any of the frailty criteria.

Finally, prevention of strength loss due to age-related sarcopenia is known to require exercise as well as adequate protein intake.

So, it was somewhat surprising that no difference in the association between protein intake and frailty was seen in women with high physical activity compared with those with lower physical activity levels. However, this may be because the range in activity level between the women in this study was relatively small. There didn’t appear to be a significant number of “gym rats” among the women in this study.

What Kind Of Protein Is Best For You?

One take-away from this study is clear. If you are a woman and want to minimize sarcopenia (loss of muscle mass and strength as you age), plant protein is an excellent choice.

A variety of plant proteins is best, so you get all the essential amino acids.

You don’t need to become a vegan. This study showed that replacing as little as 5% of your calories from animal protein with plant protein can have a significant benefit. Any healthy primarily plant-based diet will do.

This study enrolled only women aged 60 or above, so we don’t know whether the results apply to men or to younger women.

We don’t know why plant protein is better than animal protein at preventing age-related sarcopenia.

It could be because primarily plant-based diets are anti-inflammatory, and inflammation plays a role in sarcopenia.

Or it could be because primarily plant-based diets reduced the risk of chronic diseases, and chronic diseases can lead to loss of strength.

To be clear, this is a study that focuses on the type of protein that is best for long-term health and strength as we age. This is not a study of the best protein for increasing muscle mass following a workout.

Multiple studies show that whey protein can be a good post-workout choice.

However, other studies show that plant protein can also be a good post-workout choice if extra leucine is added to make it equivalent to whey protein in terms of leucine content.

The Bottom Line

You have probably heard that it is all downhill after age 30. But it doesn’t have to be.

One of the downhill slopes we all face is something called sarcopenia (age-related muscle loss). The resulting loss of strength and agility can severely impact our quality of life in our golden years.

We can prevent sarcopenia with the combination of a high protein diet and resistance training (weight bearing exercise).

But what kind of protein is best? In this issue of “Health Tips From the Professor” I review a large, well-designed study that suggests plant protein is the best choice for women if they wish to reduce age-related muscle loss and the weakness that comes with it.

For more details about the study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

______________________________________________________________________________

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

_____________________________________________________________________

About The Author

Are Vegan Diets Bad For Your Bones?

May 25, 2021 by Dr. Steve Chaney

The Secrets To A Healthy Vegan Diet

Author: Dr. Stephen Chaney

Osteoporosis is a debilitating and potentially deadly disease associated with aging. It affects 54 million Americans. It can cause debilitating back pain and bone fractures. 50% of women and 25% of men over 50 will break a bone due to osteoporosis. Hip fractures in the elderly due to osteoporosis are often a death sentence.

As I discussed in a previous issue of “Health Tips From The Professor”, a “bone-healthy lifestyle requires 3 essentials – calcium, vitamin D, and weight bearing exercise. If any of these three essentials is presence in inadequate amounts, you can’t build healthy bones. In addition, other nutrients such as protein, magnesium, zinc, vitamin B12, and omega-3 fatty acids may play supporting roles.

Vegan and other plant-based diets are thought to be very healthy. They decrease the risk of heart disease, diabetes, and some cancers. However, vegan diets tend to be low in calcium, vitamin D, zinc, vitamin B12, protein, and omega-3 fatty acids. Could vegan diets be bad for your bones?

A meta-analysis of 9 studies published in 2009 (LT Ho-Pham et al, American Journal of Clinical Nutrition 90: 943-950, 2009) reported that vegans had 4% lower bone density than omnivores, but concluded this difference was “not likely to be clinically relevant”.

However, that study did not actually compare bone fracture rates in vegans and omnivores. So, investigators have followed up with a much larger meta-analysis (I Iguacel et al, Nutrition Reviews 77, 1-18, 2019) comparing both bone density and bone fracture rates in vegans and omnivores.

How Was This Study Done?

The investigators searched the literature for all human clinical studies through November 2017 that compared bone densities and frequency of bone fractures of people consuming vegan and/or vegetarian diets with people consuming an omnivore diet.

Vegan diets were defined as excluding all animal foods.

Vegetarian diets were defined as excluding meat, poultry, fish, seafood, and flesh from any animal but including dairy foods and/or eggs. [Note: The more common name for this kind of diet is lacto-ovo vegetarian, but I will use the author’s nomenclature in this review.]

Omnivore diets were defined as including both plant and animal foods from every food group.

The investigators ended up with 20 studies that had a total of 37,134 participants. Of the 20 studies, 9 were conducted in Asia (Taiwan, Vietnam, India, Korea, and Hong-Kong), 6 in North America (the United States and Canada), and 4 were conducted in Europe (Italy, Finland, Slovakia, and the United Kingdom).

Are Vegan Diets Bad For Your Bones?

Here is what the investigators found:

Bone density: The clinical studies included 3 different sites for bone density measurements – the lumbar spine, the femoral neck, and the total body. When they compared bone density of vegans and vegetarians with the bone density of omnivores, here is what they found:

Lumbar spine:

- Vegans and vegetarians combined had a 3.2% lower bone density than omnivores.

- The effect of diet was stronger for vegans (7% decrease in bone density) than it was for vegetarians (2.3% decrease in bone density).

Femoral neck:

- Vegans and vegetarians combined had a 3.7% lower bone density than omnivores.

- The effect of diet was stronger for vegans (5.5% decrease in bone density) than it was for vegetarians (2.5% decrease in bone density).

Whole body:

- Vegans and vegetarians combined had a 3.2% lower bone density than omnivores.

- The effect of diet was statistically significant for vegans (5.9% decrease in bone density) but not for vegetarians (3.5% decrease in bone density). [Note: Statistical significance is not determined by how much bone density is decreased. It is determined by the size of the sample and the variations in bone density among individuals in the sample.]

Bone Fractures: The decrease in bone density of vegans in this study was similar to that reported in the 2009 study I discussed above. However, rather than simply speculating about the clinical significance of this decrease in bone density, the authors of this study also measured the frequency of fractures in vegans, vegetarians, and omnivores. Here is what they found.

Vegans and vegetarians combined had a 32% higher risk of bone fractures than omnivores.

The effect of diet on risk of bone fractures was statistically significant for vegans (44% higher risk of bone fracture) but not for vegetarians (25% higher risk of bone fractures).

These data suggest the decreased bone density in vegans is clinically significant.

The authors concluded, “The findings of this study suggest that both vegetarian and vegan diets are associated with lower bone density compared with omnivorous diets. The effect of vegan diets on bone density is more pronounced than the effect of vegetarian diets, and vegans have a higher fracture risk than omnivores. Both vegetarian and vegan diets should be appropriate planned to avoid dietary deficiencies associated with bone health.”

The Secrets To A Healthy Vegan Diet

The answer to this question lies in the last statement in the author’s conclusion, “Both vegetarian and vegan diets should be appropriate planned to avoid dietary deficiencies associated with bone health.”

The problem also lies in the difference between what a nutrition expert considers a vegan diet and what the average consumer considers a vegan diet. To the average consumer a vegan diet is simply a diet without any animal foods. What could go wrong with that definition? Let me count the ways.

Sugar and white flour are vegan. A vegan expert thinks of a vegan diet as a whole food diet – primarily fruits, vegetables, whole grains, beans, nuts, and seeds. A vegan novice includes all their favorites – sodas, sweets, and highly processed foods. And that may not leave much room for healthier vegan foods.

2) Big Food, Inc is not your friend. Big Food tells you that you don’t need to give up the taste of animal foods just because you are going vegan. They will just combine sugar, white flour, and a witch’s brew of chemicals to give you foods that taste just like your favorite meats and dairy foods. The problem is these are all highly processed foods. They are not healthy. Some people call them “fake meats” or “fake cheeses”. I call them “fake vegan”.

If you are going vegan, embrace your new diet. Bean burgers may not taste like Big Macs, but they are delicious. If need other delicious vegan recipe ideas, I recommend the website https://forksoverknives.com.

3) A bone healthy vegan diet is possible, but it’s not easy. Let’s go back to the author’s phrase “…vegan diets should be appropriate planned to avoid dietary deficiencies associated with bone health.” A vegan expert will do the necessary planning. A vegan novice will assume all they need to do is give up animal foods.

As I said earlier, vegan diets tend to be low in calcium, vitamin D, zinc, vitamin B12, protein, and omega-3 fatty acids. Let’s look at how a vegan expert might plan their diet to get enough of those bone-healthy nutrients.

- Calcium. The top plant sources of calcium are leafy greens and soy foods at about 100-250 mg (10-25% of the DV) of calcium per serving. Some beans and seeds are moderately good sources of calcium. Soy foods are a particularly good choice because they are a good source of calcium and contain phytoestrogens that stimulate bone formation.

A vegan expert makes sure they get these foods every day and often adds a calcium supplement.

- Protein. Soy foods, beans, and some whole grains are the best plant sources of protein.

It drives me crazy when a vegan novice tells me they were told they can get all the protein they need from broccoli and leafy greens. That is incredibly bad advice.

A vegan expert makes sure they get soy foods, beans, and protein-rich grains every day and often adds a protein supplement.

- Zinc. There are several plant foods that supply around 20% the DV for zinc including lentils, oatmeal, wild rice, squash and pumpkin seeds, quinoa, and black beans.

A vegan expert makes sure they get these foods every day and often adds a multivitamin supplement containing zinc.

- Vitamin D and vitamin B12. These are very difficult to get from a vegan diet. Even vegan experts usually rely on supplements to get enough of these important nutrients.

4) Certain vegan foods can even be bad for your bones. I divide these into healthy vegan foods and unhealthy “vegan” foods.

- Healthy vegan foods that can be bad for your bones include.

- - Pinto beans, navy beans, and peas because they contain phytates.

- - Raw spinach & swiss chard because they contain oxalates.

- - Both phytates and oxalates bind calcium and interfere with its absorption.

- - These foods can be part of a healthy vegan diet, but a vegan expert consumes them in moderation.

- Unhealthy “vegan” foods that are bad for your bones include sodas, salt, sugar, and alcohol.

- - The mechanisms are complex, but these foods all tend to dissolve bone.

- - A vegan expert minimizes them in their diet.

5) You need more than diet for healthy bones. At the beginning of this article, I talked about the 3 essentials for bone formation – calcium, vitamin D, and exercise. You can have the healthiest vegan diet in the world, but if you aren’t getting enough weight bearing exercise, you will have low bone density. Let me close with 3 quick thoughts:

- None of the studies included in this meta-analysis measured how much exercise the study participants were getting.

- The individual studies were generally carried out in industrialized countries where many people get insufficient exercise.

- The DV for calcium in the United States is 1,000-1,200 mg/day for adults. In more agrarian societies dietary calcium intake is around 500 mg/day, and osteoporosis is almost nonexistent. What is the difference? These are people who are outside (vitamin D) doing heavy manual labor (exercise) in their farms and pastures every day.

In summary, a bone healthy vegan lifestyle isn’t easy, but it is possible if you work at it.

The Bottom Line

A recent meta-analysis asked two important questions about vegan diets.

Do vegans have lower bone density than omnivores?

2) Is the difference in bone density clinically significant? Are vegans more likely to suffer from bone fractures?

The study found that:

Vegans had 5.5%–7% lower bone density than omnivores depending on where the bone density was measured.

Vegans were 44% more likely to suffer from bone fractures than omnivores.

The authors of the study concluded, ““The findings of this study suggest that…vegan diets are associated with lower bone density compared with omnivorous diets, and vegans have a higher fracture risk than omnivores…Vegan diets should be appropriate planned to avoid dietary deficiencies associated with bone health.”

In evaluating the results of this study, I took a detailed look at the pros and cons of vegan diets and concluded, “A bone healthy vegan lifestyle isn’t easy, but it is possible if you work at it.”

For more details about study and my recommendations for a bone healthy vegan lifestyle read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Does Vitamin D Affect Muscle Strength?

April 28, 2020 by Dr. Steve Chaney

Why Is Vitamin D Research So Controversial?

Most people lose muscle strength as they age, something called sarcopenia. This is not a trivial matter. Loss of muscle mass:

Leads to loss of mobility. It can also make it difficult to do simple things like lifting your grandchild or carrying a bag of groceries.

Increases your risk of falling. This often leads to serious fracture which increases your of dying prematurely. In fact, bone fractures increase your risk of dying by 3-fold or more. Even in those who recover their mobility and quality of life may never be the same.

Lowers your metabolic rate. This increases your risk of obesity and all the diseases that are associated with obesity.

Loss of muscle strength as we age is preventable. There are several things we can do to preserve muscle strength as we age, but in today’s article I will focus on the effect of vitamin D on muscle strength.

What if something as simple as preventing vitamin D deficiency could improve muscle strength as we age? That idea has been around for a decade or more. But, for reasons I will detail below, it has proven controversial. Let me start by sharing the latest study on vitamin D and muscle strength (N Aspell et al, Clinical Investigations in Ageing, volume 2019:14, pages 1751-1761).

How Was The Study Done?

The data for this study came from 4157 adults who were enrolled in the English Longitudinal Study On Aging. Participants in this study were all over the age of 60 and were still living in their own homes. The general characteristics of the study population were:

Their average age was 69.8 with 45% male and 55% female.

While 76% of the participants rated their health as “good” or above

- 73% were overweight or obese.

- 54% had a longstanding disease that limited mobility.

- 29% were taking multiple medications.

Serum 25-hydroxy vitamin D levels were determined as a measure of vitamin D status.

22% of the participants were vitamin D deficient (<30 nmol/L 25-hydroxy vitamin D).

34% of the participants were vitamin D insufficient (between 30 and 50 nmol/L 25-hydroxy vitamin D).

46% of the participants had adequate vitamin D status (>50 nmol/L 25-hydroxy vitamin D).

Muscle strength was assessed by a handgrip strength test with the dominant hand. Muscle performance was assessed with something called the short physical performance battery (SPPB), consisting of a walking speed test, a repeated chair raise test, and a balance test.

Does Vitamin D Affect Muscle Strength?

When the data on handgrip strength were analyzed:

Only 22% of the participants who had adequate vitamin D status had low handgrip strength.

40% of participants who were vitamin D deficient had low handgrip strength. That’s almost a 2-fold difference.

Handgrip strength increased linearly with vitamin D status.

- The relationship between vitamin D status and handgrip strength was highly significant (p<001).

- The beneficial effect of vitamin D status on handgrip strength plateaued at around 55-69 nmol/L 25-hydroxy vitamin D. In other words, you need adequate vitamin D status to support muscle strength, but higher levels provide no additional benefit.

When the data on muscle performance (the SPPB test) were analyzed:

Only 8% of the participants who had adequate vitamin D status scored low on this test.

25% of participants who were vitamin D deficient scored low on this test. That’s a 3-fold difference.

Muscle performance also increased linearly with vitamin D status.

- The relationship between vitamin D status and muscle performance was also highly significant (p<001).

- The beneficial effect of vitamin D status on muscle performance also plateaued at around 55-69 nmol/L 25-hydroxy vitamin D.

The authors concluded: “Vitamin D deficiency was associated with impaired muscle strength and performance in a large study of community-dwelling older people. It is generally accepted that vitamin D deficiency should be reversed to prevent bone disease. This strategy may also protect skeletal muscle function in aging.”

Why Is Vitamin D Research So Controversial?

You can be forgiven if you are saying to yourself: “I’ve heard this sort of thing before. I see a blog or headline claiming that vitamin D has a certain benefit, but it’s usually followed by later headlines saying those claims are false. Why can’t the experts agree? Is all vitamin D research bogus?”

The relationship between vitamin D status and muscle strength is no different.

Most, but not all, studies looking at the association between vitamin D status and muscle strength find that vitamin D status affects muscle strength.

However, many randomized, placebo-controlled clinical trials looking at the effect of vitamin D supplementation on muscle strength have come up empty.

A meta-analysis (L Rejnmark, Therapeutic Advances in Chronic Disease, 2: 25-37, 2011) of randomized, placebo-controlled clinical trials of vitamin D supplementation and muscle strength provides insight as to why so many of them come up empty.

The meta-analysis combined data from 16 clinical trials. The conclusions were similar to what other meta-analyses have found:

Seven of the studies showed a benefit of vitamin D supplementation on muscle strength. Nine did not.

When the data from all 16 studies were combined, there was only a slight beneficial effect of vitamin D supplementation on muscle strength.

However, it was in the discussion that the reason for these discrepancies became apparent. There were three major deficiencies in study design that were responsible for the discrepancies.

1) There was a huge difference in study design.

- The subjects were of different ages, genders, and ethnicities.

- The dose of vitamin D supplementation varied.

- Different measures of muscle strength and performance were used.

Until the scientific and medical community agree on a standardized study design it will be difficult to obtain consistent results.

While this deficiency explains the variation in outcomes from study to study, there are two other deficiencies in study design that explain why many of the studies failed to find an effect of vitamin D on muscle strength. I call this “Garbage In, Garbage Out”. Simply put, if the study has design flaws, it may be incapable of detecting a positive effect of vitamin D on muscle strength.

2) Many of the studies did not measure vitamin D status of the participants at the beginning of the study.

- The results of the study described above show that additional vitamin D will be of little benefit for anyone who starts the study with an adequate vitamin D status.

- In the study above 46% of the participants had adequate vitamin D status. This is typical for the elderly community. When almost 50% of the participants in a study have adequate vitamin D status at the beginning of a study it becomes almost impossible to demonstrate a beneficial effect of vitamin D supplementation on any outcome.

It is essential that future studies of vitamin D supplementation start with participants who have low vitamin D status. Otherwise, you are almost guaranteeing a negative outcome.

3) Most of the studies ignored the fact that vitamin D status is only one of three factors that are essential for muscle strength.

- In the case of muscle strength, especially in the elderly, the three essentials are vitamin D, protein, and exercise. All three are needed to maintain or increase muscle strength. Simply put, if one is missing, the other two will have little or no effect on muscle strength. Unfortunately, you cannot assume that exercise and protein intake are adequate in older Americans:

- - Many older adults don’t get enough exercise because of physical limitations.

- - Many older adults do not meet RDA recommendations for protein intake. That’s because physical and/or psychological limitations often interfere with their ability and interest in preparing healthy meals.

- - To make matters even worse, many experts feel that the RDA underestimates the protein requirements of the elderly.

Unfortunately, many clinical studies on the effect of vitamin D supplementation and muscle strength fail to include exercise and adequate protein intake in the study. Such clinical trials are doomed to failure.

Now you know why vitamin D research is so controversial. Until the scientific and medical community get their act together and perform better designed experiments, vitamin D research will continue to be controversial and confusing.

What Does This Mean For You?

Loss of muscle mass as we age is not a trivial matter. As described above, it:

Leads to loss of mobility.

Increases your risk of falling. This often leads to serious fracture which increase your risk of disability and death.

Lowers your metabolic rate, which increases your risk of obesity and obesity-related diseases.

So, what can you do prevent loss of muscle mass as you age? The answer is simple:

1) Aim for 25-30 grams of high-quality protein in each meal.

- That protein can come from meat, fish, eggs, or legumes.

- That doesn’t mean you need to consume an 8-ounce steak or a half chicken. 3-4 ounces is plenty.

- However, it does mean you can’t subsist on green salads and leafy greens alone. They are healthy, but you need to include a good protein source if you are going to meet your protein needs.

2) Aim for 150 minutes of moderate intensity exercise per week.

- At least half of that exercise should be resistance exercise (lifting weights, for example).

- If you have physical limitations, consult your doctor and a physical therapist or personal trainer to design resistance exercises you can do.

- Aim for a variety of resistance exercises. You will only strengthen the muscles you exercise.

3) Aim for an adequate vitamin D status.

- Start with a multivitamin containing at least 800 IU of vitamin D3.

- Because there is large variation in the efficiency with which we convert vitamin D to 25-hydroxy vitamin D, you should get your serum 25-hydroxyvitamin D tested on a yearly basis. Your health professional can tell you if you need to take larger amounts of vitamin D3.

- This study suggests that a serum 25-hydroxy vitamin D level of 55-69 nmol/L is optimal, and higher levels provide no additional benefit. That means there is no need to take mega-doses of vitamin D3 unless directed by your health professional.

The Bottom Line

A recent study looked at the effect of vitamin D status on muscle strength and performance in a healthy population with an average age of 69.

When they looked at handgrip strength:

Only 22% of the participants with an adequate vitamin D status had low handgrip strength.

40% of participants who were vitamin D deficient had low handgrip strength. That’s almost a 2-fold difference.

Handgrip strength increased linearly with vitamin D status.

When they looked at muscle performance:

Only 8% of the participants with an adequate vitamin D status scored low on this test.

25% of participants who were vitamin D deficient scored low on this test. That’s a 3-fold difference.

Muscle performance also increased linearly with vitamin D status.

If we look at the research more broadly, there are three factors that are essential for maintaining muscle mass as we age: exercise, protein, and vitamin D. Therefore, my recommendations are to:

1) Aim for 25-30 grams of high-quality protein in each meal.

2) Aim for 150 minutes of moderate intensity exercise per week. At least half of that exercise should be resistance exercise.

3) Aim for an adequate vitamin D status (>50 nmol/L of serum 25-hydroxy vitamin D). A good place to start is with a multivitamin providing at least 800 IU of vitamin D3.

For more details on my recommendations and a discussion of why studies on vitamin D supplementation are often confusing, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.