Blood Pressure 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.

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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

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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.

Which Exercise Is Best For Reducing Blood Pressure?

October 29, 2024 by Dr. Steve Chaney

How Can You Keep Your Blood Pressure Under Control?

Author: Dr. Stephen Chaney

Hypertension (high blood pressure) is called a silent killer. That’s because you often don’t notice any symptoms until you die from a stroke or heart attack.

Nearly half of all American adults (120 million or 48%) have high blood pressure. Of Americans with high blood pressure:

About half (46%) of them don’t know it.

And of those who know they have high blood pressure:

Only half of them have it under control.

- In case you weren’t doing the math, that means that only 1 in 4 Americans with high blood pressure has it under control.

That is scary because every 20 mm Hg increase in systolic blood pressure:

Doubles your risk of death from a stroke or heart attack.

And if the personal costs of high blood pressure were not enough, the cost of high blood pressure to our health care system is enormous.

The CDC estimates that the cost of high blood pressure in the United States is around $131 to $198 billion per year. And this may be an underestimate because it does not include productivity losses from non-fatal illnesses caused by high blood pressure.

Medications are effective at reducing blood pressure, but they have significant side effects. And those side effects have two unintended consequences.

Around half of patients stop taking their blood pressure medication within the first year because of side effects or cost.

For patients who continue taking blood pressure medication, they are usually prescribed other medications to reduce the side effects from their blood pressure medication.

This is often the start of a downward spiral in which they need more medications to reduce the side effects of the medicines they were just prescribed. And they end up on multiple medications, and a poor quality of life because of it.

Because of this, many patients and health care practitioners are looking for natural ways to keep blood pressure under control. One of the most recommended approaches is to increase exercise, and the type of exercise most frequently recommended is aerobic exercise.

But is that the best advice? That advice is based on clinical studies performed 20 to 30 years ago. And those studies were an excellent example of “the tail wagging the dog”.

Let me explain. In the early days most experts believed that aerobic exercise would be the most effective exercise for reducing blood pressure. So, most of the original studies on the effect of exercise at reducing blood pressure were done using aerobic exercise.

From those studies we knew that aerobic exercise was effective at reducing blood pressure, but we didn’t really know whether it was the most effective exercise for reducing blood pressure. And more recent studies have suggested a more nuanced view of exercise and blood pressure control.

For that reason, the authors of the current article (JJ Edwards et al, British Journal of Sports Medicine, 57: 1317-1326, 2023) decided to conduct a comprehensive review of all randomized controlled studies between 1990 and February 2023 on the effect of exercise on reducing blood pressure.

How Was The Study Done?

The investigators performed a comprehensive, systematic review of all randomized controlled studies (meaning patients were randomly assigned to an exercise or non-exercise group) looking at reductions in blood pressure following an exercise intervention of ≥ 2 weeks.

They excluded studies that:

Included dietary counseling or exercise recommendations in the control group.

Included dietary counseling, supplementation, or medication in the exercise group.

However, there were no exclusions based on the health or disease state in the patient population.

Their analysis included 270 randomized controlled trials with a total of 15,827 participants. All the studies reported systolic and/or diastolic blood pressure before and after the exercise intervention.

Exercise interventions were divided into five classifications:

Aerobic exercises.
Resistance exercises.
Combined exercises (a combination of aerobic and resistance exercises).
High-intensity interval exercises (high-intensity, short-duration exercises).
Isometric exercises.

Several of these exercise classifications were further subdivided into individual exercises (see below)

Which Exercise Is Best For Reducing Blood Pressure?

When the reduction in systolic blood pressure was considered, the rank order of exercise effectiveness was:

High-intensity interval exercise (4.08 mm Hg reduction).
Aerobic exercise (4.48 mm Hg reduction).
Resistance exercise (4.53 mm Hg reduction).
Combined aerobic and resistance exercise (6.04 mm Hg reduction).
Isometric exercise (8.24 mm Hg reduction).

When the reduction in diastolic blood pressure was considered, the amount of reduction was less but the rank order of exercise effectiveness was the same:

High-intensity interval exercise (2.50 mm Hg reduction).
Aerobic exercise (2.53 mm Hg reduction).
Resistance exercise (3.04 mm Hg reduction).
Combined aerobic and resistance exercise (3.54 mm Hg reduction).
Isometric exercise (4.00 mm Hg reduction).

When the exercise classifications were subdivided into individual exercises.

Running and cycling were significantly more effective than walking for aerobic exercise, with running being the most effective form of aerobic exercise.
Cycling was the most effective form of high-intensity interval exercise.
No effect of exercise type was seen for the effectiveness of resistance training.
Isometric wall squats and leg extensions were much more effective than isometric handgrip exercises.

There was not enough data from diastolic blood pressure studies to subdivide into individual exercises.

There were two other results of interest.

Aerobic exercise interventions were slightly more effective with lower exercise frequency, suggesting that 3 times a week may be more effective than 5 or more times a week.

All exercise interventions were much more effective for people with significantly elevated blood pressure than for people with slightly elevated blood pressure or normal blood pressure.

Of course, the important question for people with normal blood pressure is the effectiveness of exercise in preventing future increases in blood pressure, and this study is not designed to answer that question.

The authors concluded, “Various exercise training modes improve resting blood pressure, particularly isometric exercise. The results of this analysis should inform future exercise guideline recommendations for the prevention and treatment of arterial hypertension.”

What Does This Study Mean For You?

The takeaways from this study are clear.

If you wish to reduce your blood pressure:

Any kind of exercise is helpful, but current recommendations that prioritize aerobic exercise may be misleading.

If you want to get the most “bang for your buck”:

- Isometric exercise is the most effective and high intensity interval exercise is the least effective.

- Aerobic and resistance exercise are equally effective.

- A combination of aerobic and resistance exercise is more effective than either alone.

And if you want to know the most effective individual exercises:

- Wall squats and leg extensions are the most effective isometric exercises.

- Running and cycling are the most effective aerobic exercises.

- Any kind of resistance exercise is equally effective.

Here are my thoughts about this study:

If you haven’t been keeping up with clinical studies on exercise and blood pressure (like me), the conclusions of this comprehensive review are probably a surprise. I would not have expected isometric exercises to be more effective than aerobic exercises for lowering blood pressure.

The authors of this review postulated that isometric exercise decreases blood flow to the muscles involved. When those muscles relax, blood flow increases which sends metabolic signals that cause blood vessels to relax.

This study is good news for people with health conditions that limit their ability to do aerobic exercises or traditional resistance exercises.

We also need to remember that lowering blood pressure is not the only value of exercise.

- Aerobic exercise improves cardiovascular function.

- Resistance exercise increases muscle mass, which is particularly important for seniors who are trying to maintain muscle mass and function. Regular resistance exercise also helps minimize bone loss as we age.

Isometric exercise can be considered a form of resistance exercise, but it may need to be supplemented with resistance exercises that target other muscle groups.

As I said above, this study shows that all forms of exercise reduce blood pressure. The most effective exercise for you is the one you enjoy and will do on a regular basis.

Finally, while this study looked at the effectiveness of different exercises at reducing high blood pressure, these findings are probably also applicable to the types of exercise that can reduce risk of developing high blood pressure as we age.

How Can You Keep Your Blood Pressure Under Control?

Exercise alone is not a “magic bullet” for controlling blood pressure. And therein lies a story.

One reason so many people choose medications to control their blood pressure is that there is no “magic bullet” natural approach for controlling blood pressure. Exercise is just one part of a holistic approach for controlling blood pressure that also includes:

The DASH (Dietary Approaches To Stop Hypertension) was designed to prevent high blood pressure. I refer to it as an Americanized version of the Mediterranean diet.

Both diets are rich in fruits, vegetables, and whole grains and limit high fat meats and dairy products. And both diets have been shown to reduce the risk of high blood pressure.

Weight control. Overweight and obesity are both associated with increased risk of high blood pressure. One estimate is that every two pounds of weight gain increases blood pressure by 1 mm Hg.

Supplementation. The most effective supplements appear to be:

- Omega-3 fatty acids.

- Supplements containing grape seed extract and/or nitrates from beetroots and leafy greens.

- Calcium and magnesium if dietary intakes are not optimal.

Diet, weight control, supplementation, and exercise are the top 4 lifestyle factors for keeping blood pressure under control, but a comprehensive holistic approach to controlling blood pressure includes:

Low sodium/potassium ratio. I mention it here for completeness, but it is an integral part of the DASH diet.

Stress management. Chronic stress can increase blood pressure.

Adequate sleep.

We may be outliers, but my wife and I have followed this approach for years and in our 80s have the blood pressure of teenagers.

The Bottom Line

Most experts recommend aerobic exercise for reducing blood pressure, but these recommendations are based on outdated studies. A recent study examined the effectiveness of various exercises at reducing blood pressure based on all randomized controlled clinical trials between 1990 and 2023.

This study shows:

If you wish to reduce your blood pressure:

Any kind of exercise is helpful, but current recommendations that prioritize aerobic exercise may be misleading.

If you want to get the most “bang for your buck”:

- Isometric exercise is the most effective and high intensity interval exercise is the least effective.

- Aerobic and resistance exercise are equally effective.

- A combination of aerobic and resistance exercise is more effective than either alone.

For more information on this study, what it means for you, and recommendations for a holistic approach for controlling blood pressure naturally, 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.

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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 Omega-3s Are Best For Blood Pressure?

April 2, 2024 by Dr. Steve Chaney

What Does This Study Mean For You?

Author: Dr. Stephen Chaney

I am continuing my series on recent omega-3 breakthroughs. Today I am going to cover a recent systematic review and meta-analysis (X Zhang et al, Journal of the American Heart Association, 11: e025071, 2022) that analyzed 71 double blind, placebo-controlled clinical studies with 4,973 subjects to determine the optimal dose of omega-3s needed to lower blood pressure.

But first, I will cover why this study is so important.

High blood pressure is called a “silent killer”. For most of us our blood pressure creeps up year after year, decade after decade. Factors like inactivity, obesity, smoking, poor diet, and excess alcohol consumption speed the increase.

Unfortunately, the symptoms of high blood pressure – things like headaches, anxiety, fatigue, and blurred vision – are easy to ignore or confuse with other health problems. And if these symptoms are ignored long enough, the result can be sudden death due to a stroke or heart attack.

Alternately, the consequence could be things like congestive heart failure, kidney failure, vision loss, and memory loss that change your quality of life forever. And once the genie is out of the bottle, it can never be put back again. The damage is permanent.

Omega-3s are often recommended for keeping blood pressure in the normal range. In fact, in 2019 the FDA approved a qualified health claim stating, “Consuming eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) omega-3 fatty acids in food or dietary supplements may reduce the risk of hypertension (high blood pressure) and coronary heart disease.”

But the amount of omega-3s needed to reduce the risk of high blood pressure is uncertain. Previous studies have come up with conflicting results. That is the question the study I will discuss today was designed to answer.

How Was This Study Done?

The investigators included 71 studies published between 1987 and 2020 with a total of 4,793 subjects ranging in age from 22 to 86 years in their systematic review and meta-analysis. The studies were all randomized, placebo-controlled trials looking at the effectiveness of omega-3 intake (primarily in the form of food or supplements containing both EPA and DHA) at lowering blood pressure. The placebo used in these studies was olive oil or other vegetable oils.

The studies included in this meta-analysis:

Included omega-3 intake from both diet (mackerel, salmon, trout, or tuna) and supplements (fish oil, algal oil, or purified omega-3 ethyl esters).

Were conducted in populations from Europe, North America, Australia and other Pacific islands, and Asia.

Included subjects with normal blood pressure as well as those with high blood pressure.

Ranged in length from 5 to 52 weeks (the average was 10 weeks).

Included approximately equal numbers of men and women.

The meta-analysis excluded studies that:

Lacked a placebo.

Lasted less than 4 weeks.

Included blood pressure medications.

Included individuals with preexisting cardiovascular events.

The data from these trials was analyzed by a statistical method called a 1-stage cubic spline regression model. This is a recently developed statistical method which the investigators stated was superior to the statistical methods used in previous studies because it reduces the likelihood the results are influenced by investigator bias.

How Much Omega-3s Are Best For Blood Pressure?

When the investigators combined the data from all 71 studies:

The maximum reduction in both systolic and diastolic blood pressure was observed between 2g/d and 3 g/d.

The dose response was non-linear. Doses above 3 g/d offered no additional benefit.

When the investigators looked at subgroups within the studies:

Reduction in blood pressure was seen in both subjects with normal blood pressure and those with high blood pressure.

- However, reduction in blood pressure and the dose response were different in the two groups.

- - In subjects with normal blood pressure the dose response was non-linear with the optimum reduction between 2 and 3 g/d.

- - In subjects with high blood pressure the reduction in blood pressure was greater and the dose response was linear. The authors recommended a dose ≤ 3 g/d EPA + DHA for people with high blood pressure.

Subjects with hyperlipidemia had a greater reduction in blood pressure than subjects with normal lipid levels, and the dose-response was linear.

Subjects over the age of 45 had a greater reduction in blood pressure than subjects under the age of 45, and the dose response was linear.

There were no significant differences between:

- Diet versus supplementation.

- Type of omega-3 supplement (natural fish oil versus purified ethyl ester).

- Sex.

The authors concluded, “This dose-response meta-analysis demonstrates that the optimal combined intake of omega-3 fatty acids for blood pressure lowering is likely between 2 g/d and 3 g/d. Doses of omega-3 fatty acid intake above the recommended 3 g/d may be associated with additional benefits in lowering blood pressure among groups at high risk of cardiovascular disease.”

I should probably explain the reasoning behind this conclusion.

79% of the studies included in this meta-analysis were performed with subjects who had normal blood pressure. This group had a non-linear reduction in blood pressure with an optimal reduction between 2 and 3 g/d EPA + DHA.

- Because of its size this group exerted a major influence on the results, which explains why the average results for the entire group showed a non-linear reduction in blood pressure with an optimal reduction between 2 and 3 g/d EPA + DHA.

- Subjects with normal blood pressure and normal lipid levels are at low risk of cardiovascular disease. The high-risk groups (high blood pressure, high cholesterol and/or triglyceride levels, and over 45) all had a linear dose response suggesting that doses above 3 g/d EPA + DHA may be optimal.

The authors also said, “We found associations [between omega-3 intake and blood pressure] among both hypertensive (high blood pressure) and nonhypertensive (normal blood pressure) groups, suggesting that omega-3 fatty acids could be beneficial for controlling blood pressure even before the onset of hypertension.

This means that the intake of omega3 fatty acids could have implications on a person’s future risk of stroke, ischemic heart disease, and all-cause mortality.”

In other words, they are saying their data suggests that EPA + DHA intakes in the 2-3 g/d range may prevent high blood pressure and the effects it can have on our health.

What Does This Study Mean For You?

The authors of this study claim their data support a dose of 2-3 mg/d of EPA + DHA to prevent a future increase in blood pressure and all its associated health consequences. They also say that an EPA+ DHA dose ≥ 3g/d may be optimal for people who already have high blood pressure and/or other risk factors for heart disease.

I am not an expert on statistics, so I cannot evaluate the author’s claim that their statistical method was superior to the methods used in earlier studies that gave conflicting results.

However, their results are consistent with recommendations of several major health and government agencies.

For example, the European Food Safety Authority has said, “An intake of EPA and DHA of ~3 g/d is required to bring out the claimed hypotensive (blood pressure lowering) effect”.

The FDA has approved qualified health claims stating that consuming EPA and DHA in foods or dietary supplements may reduce the risk of hypertension (high blood pressure) and coronary heart disease but did not recommend a dose to achieve these results.

The American Heart Association has recommended ~ 1 g/d of EPA + DHA for patients with documented coronary heart disease and 2–4 g/day of EPA + DHA to lower triglycerides.

And the American Heart Association features this article on their website with the headline, “Consuming about 3 grams of omega-3 fatty acids a day may lower blood pressure.”

When we contrast that with the fact that the average American gets less than 100 mg/d of EPA + DHA from their diet it is obvious that many Americans would likely benefit from increasing the amount of EPA and DHA in their diet.

The Rest Of The Story

There are four additional points I would like to make:

In trying to explain the differences between dose response in high and low risk subjects, the authors said, “There could be mechanistic differences in bioavailability and efficacy of omega-3 fatty acid intake in these populations.”

In last week’s “Health Tips From the Professor” article I reviewed a study that measured individual differences in the utilization of EPA and DHA and concluded that a blood measurement called Omega-3 Index was a more reliable indicator of health outcomes than the dose of omega-3s consumed.

For that reason, I recommend personalizing your dose of EPA + DHA to reach an Omega-3 Index of 8%, which appears to be optimal for heart health and provides significant blood pressure reduction. This is an iterative process which will require frequent measurement of your omega-3 index and adjustment of EPA + DHA dose until you find the level of EPA + DHA supplementation you need to achieve an Omega-3 Index of 8%.

This study and similar studies measure the health benefits of the long chain omega-3 fatty acids EPA and DHA. Short chain omega-3s from nuts, seeds, and plant oils are healthy, but their conversion to EPA and DHA is very inefficient.

Both the FDA and American Heart Association recommend that doses of EPA + DHA above 3 g/d should be taken under a physician’s supervision because high doses can cause bleeding problems.

This is another reason for basing your intake of EPA + DHA on Omega-3 Index rather than on the dose recommended by a clinical study. Based on dozens of clinical studies, an Omega-3 Index of 8% appears to be safe unless you have a bleeding disorder or are on a blood-thinning medication (see below).

If you are on a medication to thin your blood, you should consult with your physician before increasing or decreasing your omega-3 intake because changes in dietary omega-3s can affect the optimal dose of medication they prescribe.

The Bottom Line

A recent study looked at the dose of EPA + DHA needed to lower blood pressure.

The study concluded that a dose of 2-3 mg/d of EPA + DHA was optimal for preventing a future increase in blood pressure and all its associated health consequences.

It also concluded that an EPA+ DHA dose ≥ 3g/d was optimal for lowering blood pressure in people who already have high blood pressure and/or other risk factors for heart disease.

Based on previous studies, I recommend optimizing your omega-3 index rather than relying on a dose of EPA + DHA that may not be right for you.

For more details about this study and what it means to 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.

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

About The Author

Eating Of The Green

March 29, 2022 by Dr. Steve Chaney

Why Is Eating Green Good For Your Heart?

Author: Dr. Stephen Chaney

You may be one of the millions of Americans who celebrated St. Patrick’s Day a couple of weeks ago. If so, you may have sung the famous Irish folk song “The Wearing of the Green”. If you are Irish, that song has special meaning for you. However, when I hear that song, I think of “Eating of the Green.”

And when I think of eating green, I don’t mean that everything we eat should be green. I am thinking of whole fruits and vegetables in a variety of colors. We have known for years that fruits and vegetables are good for our health. Consumption of fruits and vegetables is associated a lower risk of high blood pressure, heart disease, cancer, inflammatory diseases, and much more.

For today’s health tip, I am going to focus on heart health and an unexpected explanation for how fruits and vegetables reduce our risk of heart disease.

Why Is Eating Green Good For Your Heart?

We have assumed that whole fruits and vegetables lower our risk of heart disease because they are low in saturated fats and provide heart-healthy nutrients, phytonutrients, and fiber. All of that is true. But could there be more?

Recent research has suggested that the nitrates found naturally in fruits and vegetables may also play a role in protecting our hearts. Here is what recent research shows:

The nitrates from fruits and vegetables are converted to nitrite by bacteria in our mouth and intestines.

- Fruits and vegetables account for 80% of the nitrate in our diet. The rest comes from a variety of sources including the nitrate added as a preservative to processed meats.

- Although all fruits and vegetables contain nitrates, the best sources are green leafy vegetables and beetroot. [Beet greens are delicious and also a good source of nitrate, but beetroot is the part of the beet we usually consume.]

Nitrite is absorbed from our intestine and converted to nitric oxide by a variety of enzymes in our tissues.

Both reactions require antioxidants like vitamin C, which are also found in fruits and vegetables.

Nitric oxide has several heart healthy benefits. For example:

It helps reduce inflammation in the lining of blood vessels. Inflammation stimulates atherosclerosis, blood clot formation, and is associated with an increased risk of heart disease.

It relaxes the smooth muscle cells that surround our blood vessels. This makes the blood vessels more flexible and helps reduce blood pressure.

It prevents smooth muscle cells from proliferating, which prevents them from invading and constricting our arteries. This, in turn, has the potential to reduce the risk of atherosclerosis.

It prevents platelet aggregation. This, in turn, has the potential to reduce the risk of heart attack and stroke due to blood clots that block the flow of blood to our heart or brain.

It is well established that nitrates from fruits and vegetables reduce blood pressure. More importantly, they can help slow the gradual increase in blood pressure as we age.

However, few studies have asked whether this reduction in blood pressure translates into improved cardiovascular outcomes. This study (CP Bondonno et al, European Journal of Epidemiology, 36: 813-825, 2021) was designed to answer that question.

How Was This Study Done?

This study made use of data from the Danish Diet, Cancer, and Health Program. That program enrolled 53,150 participants from Copenhagen and Aarhus between 1993 and 1997 and followed them for an average of 21 years. None of the participants had a diagnosis of cancer or heart disease at the beginning of the study.

Other characteristics of the participants at the time they were enrolled in the study were:

46% male

Average age = 56

BMI = 26 (>20% overweight)

Average systolic blood pressure = 140 mg Hg

Average diastolic blood pressure = 84 mg Hg

At the beginning of the study, participants filled out a 192-item food frequency questionnaire that assessed their average intake of various food and beverage items over the previous 12 months. The vegetable nitrate content of their diets was analyzed using a comprehensive database of the nitrate content of 178 vegetables. For those vegetables not consumed raw, the nitrate content was reduced by 50% to account for the nitrate loss during cooking.

Blood pressure was measured at the beginning of the study. Data on the incidence (first diagnosis) of heart disease during the study was obtained from the Danish National Patient Registry. Data were collected on diagnosis of the following heart health parameters:

Cardiovascular disease (all diseases of the circulatory system).

Ischemic heart disease (lack of sufficient blood flow to the heart). The symptoms of ischemic heart disease range from angina to myocardial infarction (heart attack).

Ischemic stroke (lack of sufficient blood flow to the brain).

Hemorrhagic stroke (bleeding in brain).

Heart failure.

Peripheral artery disease (lack of sufficient blood flow to the extremities).

Is Nitrate From Vegetables Good For Your Heart?

Intake of nitrate from vegetables ranged from 18 mg/day (<1/3 serving of nitrate-rich vegetables per day) to 168 mg (almost 3 servings of nitrate-rich vegetables per day). The participants were grouped into quintiles based on their vegetable nitrate intake. When the group with the highest vegetable nitrate intake was compared to the group with the lowest vegetable nitrate intake:

Systolic blood pressure was reduced by 2.58 mg Hg.

Diastolic blood pressure was reduced by 1.38 mg Hg.

Risk of cardiovascular disease was reduced by 14%.

Risk of ischemic heart disease (angina and heart attack) was reduced by 13%.

Risk of ischemic stroke (stroke caused by lack of blood flow to the brain) was reduced by 14%.

Risk of heart failure was reduced by 17%.

Risk of peripheral artery disease was reduced by 31%.

Risk of hemorrhagic stroke (bleeding in the brain) was not significantly reduced.

Two other observations were of interest:

Blood pressure and risk of peripheral artery disease decreased with increasing vegetable nitrate intake in a relatively linear fashion. However, the other parameters of heart disease plateaued at a modest intake of vegetable nitrate intake (around one cup of nitrate-rich vegetables per day). This suggests that as little as one serving of nitrate-rich vegetables a day is enough to provide some heart health benefits.

Only about 21.9% of the improvement in heart health could be explained by the decrease in blood pressure. This is not surprising when you consider the other beneficial effects of nitric oxide described above.

The authors concluded, “Consumption of at least ~60 mg/day of vegetable nitrate (~ one serving of green leafy vegetables or beets) may mitigate risk of cardiovascular disease.”

Are Nitrates Good For You Or Bad For You?

You are probably thinking, “Wait a minute. I thought nitrates and nitrites were supposed to be bad for me. Which is it? Are nitrates good for me or bad for me?”

It turns out that nitrates and nitrites are kind of like Dr. Jekyll and Mr. Hyde. They can be either good or bad. It depends on the food they are in and your overall diet.

Remember the beginning of this article when I said that the conversion of nitrates to nitric oxide depended on the presence of antioxidants? Vegetables are great sources of antioxidants. So, when we get our nitrate from vegetables, most of it is converted to nitric oxide. And, as I discussed above, nitric oxide is good for us.

However, when nitrates and nitrites are added to processed meats as a preservative, the story is much different. Processed meats have zero antioxidants. And the protein in the meats is broken down to amino acids in our intestine. The amino acids combine with nitrate to form nitrosamines, which are cancer-causing chemicals. Nitrosamines are bad for us.

Of course, we don’t eat individual foods by themselves. We eat them in the context of a meal. If you eat small amounts of nitrate-preserved processed meats in the context of a meal with antioxidant-rich fruits and vegetables, some of the nitrate will be converted to nitric oxide rather than nitrosamines. The processed meat won’t be as bad for you.

Eating Of The Green

Your mother was right. You should eat your fruits and vegetables!

The USDA recommends at least 3 servings of vegetables and 2 servings of fruit a day.

Based on this study, at least one of those servings should be nitrate-rich vegetables like green leafy vegetables and beets.

If you don’t like any of those, radishes, turnips, watercress, Bok choy, Chinese cabbage, kohlrabi, chicory leaf, onion, and fresh garlic are also excellent sources of nitrate.

The good news is that you may not need to eat green leafy vegetables and beets with every meal. If this study is correct, one serving per day may have heart health benefits. That means you can enjoy a wide variety of fresh fruits and vegetables as you try to meet the USDA recommendations.

Finally, if you don’t like any of those foods, you may be asking, “Can’t I just take a nitrate supplement?”

For blood pressure, there are dozens of clinical trials, and the answer seems to be yes – especially when the nitrate comes from vegetable sources and the supplement also contains an antioxidant like vitamin C.

For heart health benefits, the answer is likely to be yes, but clinical trials to confirm that would take decades. Double blind, placebo-controlled trials of that duration are not feasible, so we will never know for sure.

Moreover, you would not be getting all the other health benefits of a diet full of fresh fruits and vegetables. Supplementation has its benefits, but it is not meant to replace a healthy diet.

The Bottom Line

We have known for years that fruits and vegetables are good for our hearts. We have assumed that was because whole fruits and vegetables are low in saturated fats and provide heart-healthy nutrients, phytonutrients, and fiber. But could there be more?

It is well established that nitrates from fruits and vegetables reduce blood pressure. More importantly, they can help slow the gradual increase in blood pressure as we age.

However, few studies have asked whether this reduction in blood pressure translates into improved cardiovascular outcomes. A recent study was designed to answer that question.

When the study compared people with the highest vegetable nitrate intake to people with the lowest vegetable nitrate intake:

Blood pressure was significantly reduced.

The risk of cardiovascular disease was reduced by 14%.

Risk of ischemic heart disease (angina and heart attack) was reduced by 13%.

Risk of ischemic stroke (stroke caused by lack of blood flow to the brain) was reduced by 14%.

Risk of heart failure was reduced by 17%.

Risk of peripheral artery disease was reduced by 31%.

Blood pressure and risk of peripheral artery disease decreased with increasing vegetable nitrate intake in a relatively linear fashion.

However, the other parameters of heart disease plateaued at a modest intake of vegetable nitrate intake (around one cup of nitrate-rich vegetables per day). This suggests that as little as one serving of nitrate-rich vegetables a day is enough to provide some heart health benefits.

The authors concluded, “Consumption of at least ~60 mg/day of vegetable nitrate (~ one serving of green leafy vegetables or beets) may mitigate risk of cardiovascular disease.”

Of course, you may have heard that nitrates and nitrites are bad for you. I discuss that in the article above.

For more details about this 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.