Nutritiion

What Is Epigenetics

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Can What We Eat Affect Our Kids?

Author: Dr. Stephen Chaney

 

what is epigeneticsWhat is epigenetics?  For me, the first stages of understanding came a while back.  When I was a young graduate student (which is more than just a few years ago), I was taught that all genetic information resided in our DNA. During conception, we picked up some DNA from our dad and some from our mom, and that DNA was what made us a unique individual.

We knew that environmental influences such as diet, lifestyle and exposure to toxic chemicals could affect our health personally. However, we never dreamed that the effects of those environmental influences could actually alter our gene expression, and that those genetic alterations could be passed on to our children.

Today we know that environmental influences can actually modify our DNA and that those modifications can be passed on to our offspring – a process called epigenetics.

What Is Epigenetics & How Does It Affect Gene Expression?

Simply put, epigenetics involves modifications to our DNA. DNA can be methylated or acetylated and the proteins that bind to our DNA can be modified in multiple ways. That is important for two reasons:

  • These alterations can turn genes on and off. That means that epigenetic modifications can alter gene expression.
  • These alterations can be influenced by our environment – diet, lifestyle, and exposure to environmental chemicals

In a previous “Health Tips From the Professor” article titled “Can Diet Alter Your Genetic Destiny?”  I discussed recent research suggesting that a healthy diet and lifestyle causes epigenetic changes in the DNA that may reduce your risk of heart disease, cancer and diabetes.

That alone was a monumental discovery. Even more monumental is the recent discovery that at least some of those epigenetic changes can be passed on to our children, which brings me to the question I posed in the title of this article: “Can what we eat affect our kids?”

Animal Studies Showing That Epigenetic Changes Can Be Inherited

epigenetic changes are inheritedAs is often the case, the first definitive study showed that epigenetic changes were heritable was an animal study. This study was done with a mouse strain called agouti (Waterman and Jirtle, Mol. Cell. Biol. 23: 5193 – 5300, 2003). Agouti mice can have two remarkably distinctive phenotypes. They can either have a yellow coat, become obese as adults and be prone to cancer and diabetes as they age or they can have a brown coat and grow up to be lean and healthy.

It had been known for some time that these phenotypic differences were controlled by the epigenetic methylation of a specific gene called the agouti gene. The agouti gene codes for a genetic regulator that controls coat color, feeding behavior, and body weight set-point, among other things. When the agouti gene is under methylated it is active. As a consequence the mice have yellow coats and are prone to obesity. When the agouti gene is highly methylated it is inactive. The mice have brown coats and are lean and healthy.

Moreover, methylation of the agouti gene is not a purely random event. Mothers with the yellow, obese phenotype tended to produce a preponderance of offspring with the same phenotype and vice-versa. In short, the epigenetic methylation pattern of the agouti gene could be passed from generation to generation. It was heritable.

Waterman and Jirtle’s research broke new ground by showing that the methylation of the agouti gene could be strongly influenced by what the mother ate while the fetal mice were still in the womb.

When they fed agouti mothers a diet with extra folic acid, B12, betaine and choline (all nutrients that favor DNA methylation) during conception and pregnancy the agouti gene of their offspring became highly methylated. A high percentage of those offspring had brown coats and grew up to be lean and healthy.

However, when Waterman and Jirtle put agouti mothers on a diet that was deficient in folic acid, B12, betaine and choline during conception and pregnancy the agouti gene of their offspring was under methylated. Many of those offspring had yellow coats and grew up to be fat and unhealthy.

Subsequent studies from the same laboratory have shown that:

  • Addition of genistein, a phytonutrient from soy, to the maternal diet also favors methylation of the agouti gene and protects against obesity in agouti mice (Dolinoy et al, Environmental Health Perspective, 114: 567-572, 2006).
  • The addition of the environmental toxin bisphenol A to maternal diets causes under methylation of the agouti gene and predisposes to obesity in agouti mice, but this effect can be reversed by also feeding the mother genistein or folic acid and related nutrients during pregnancy (Dolinoy et al, PNAS, 13056-13061, 2007).

The agouti mice studies provide a dramatic example of how diet and environmental exposure during pregnancy can cause epigenetic changes in fetal DNA that have long term health consequences for the offspring. However, they are animal studies. Does the same hold true for humans?

Diet, Epigenetic Changes, and Obesity in Humans

diet-epigenetic-changes-obesityWith humans, it is really difficult to determine whether epigenetic changes that occur during conception and pregnancy affect our children. That is because when you measure an epigenetic effect in a child or adult, it is difficult to sort out how much of that effect was caused by what the mom ate during pregnancy and how much was caused by how the family ate as the kids were growing up.

Unfortunately, there is a tragic human experiment that shows that the same kind of epigenetic changes are heritable in humans. I’m referring to what is known as the “Dutch Hunger Winter”. This was a period of starvation during 1944-1945, the final year of World War II, when the Germans set up a blockade that prevented food from reaching western Holland. During that few months even pregnant women were forced to live on food rations providing a little as 500 calories a day.

This was an event without parallel in human history. Holland is not a third world country. Once the blockade was lifted children born during the Hunger Winter had the same plentiful supply of food as every other Dutch citizen. This has allowed generations of research scientists to ask what were the effects of a brief exposure to malnutrition during conception and pregnancy.

The health consequences were dramatic. 50 years later individuals who were conceived during the Hunger Winter weighed about 14 pounds more, had waists about 1.5 “ larger, and were three times more likely to have heart disease than those born to mothers who were in their second or third trimester of pregnancy during that time. By the time they reached age 63, they experienced a 10% increase in mortality.

What caused those health consequences? Could the cause have been epigenetic? Recent research suggests that the answer might be yes.

A recent study analyzed epigenetic changes in DNA from blood samples of survivors born during the Hunger Winter that had been collected when they were 59 years old (Tobi et al, Int. J. Epidemiology, doi: 10.1093/ije/dyv043, 2015). This study showed:

  • A distinct pattern of DNA methylation was observed in survivors who were conceived during the Hunger Winter. This pattern of DNA methylation was not observed in survivors who were in their second or third trimester during the Hunger Winter. It was also not seen in people who were conceived immediately before or after the Hunger Winter.
  • Some of the genes with distinctive methylation patterns were genes that affected things like cholesterol levels and insulin sensitivity, which have the potential to increase disease risk.
  • Other genes with distinctive methylation patterns were genes that affected metabolism. They were “thrifty” genes that increased the efficiency of metabolism. Increased efficiency of metabolism is beneficial when calories are scarce, but can lead to obesity when calories are plentiful.

That is a truly remarkable finding when you think about it. If these data are true, they suggest that starvation during early pregnancy caused the fetus to make epigenetic changes to its DNA that allowed it to become more efficient at energy utilization, and those epigenetic changes have lasted a lifetime – even when food was abundant throughout the rest of that lifetime.

What Is Epigenetics And Can What We Eat Affect Our Kids?

can what we eat affect our kidsThe studies I featured in this article are powerful “proof of concept” that diet and environmental exposure during conception and pregnancy can result in epigenetic changes to the DNA of the offspring that can persist throughout their life and dramatically affect their health. However, it is not yet clear how they apply to you and me.

  • Agouti mice are a very special strain of mice. It is not yet clear what effect folic acid, genistein and bisphenol A have on epigenetic modification of specific human genes, and whether those epigenetic modifications will have health consequences in humans.
  • The specific circumstances of the Dutch Hunger Winter are unlikely to be repeated on any significant scale. The closest approximation I can envision would be a woman who becomes pregnant while on a very low calorie fad diet.

There are, of course, many other examples of heritable epigenetic modifications. For example:

  • When female rats are maintained on a “junk-food diet” high in fat and sugar during pregnancy and lactation their offspring show a marked preference for high fat foods (Ong & Muhlhausler, FASB J, 25: 2167-2179, 2011). They also show epigenetic alterations of the central reward pathways that may pre-condition them to require higher intakes of fat to experience pleasure from eating.
  • When rats are fed diets deficient in omega-3 fatty acids, adolescent rats from the second and subsequent generations display marked increases in hyperactivity and anxiety (For more details, see my “Health Tips from the Professor” article titled “The Seventh Generation Revisited”.
  • In a clinical trial of 162 obese Canadian mothers who had children before and after weight loss surgery, the children born after weight loss surgery were half as likely to grow up overweight or obese as the children born before the weight loss surgery (Smith et al, Journal of Clinical Endocrinology & Metabolism 94: 4275-4283, 2009), and this correlated with epigenetic modification of genes that play a role in obesity, diabetes, cancer and heart disease (Guernard et al, PNAS 110: 11439-11443, 2013).

Taken together, the existing data suggest that our diet and environmental exposure during conception and pregnancy can cause epigenetic changes to our children’s DNA that may affect their future health in ways that we can only begin to understand at present. It is a sobering thought.

 

The Bottom Line

 

  • The term epigenetics describes modifications to our DNA that turn our genes off and on.
  • In this article I discussed two powerful “proof of concept” studies, one in rats and the other in humans, showing that diet and environmental exposure during conception and pregnancy can result in epigenetic changes to the DNA of the offspring that can persist throughout their life and dramatically affect their health.
  • The health consequences of these epigenetic modifications include obesity, diabetes, cancer, heart disease, hyperactivity, anxiety and many more.
  • This is a new paradigm. Most prenatal nutrition advice is currently based on what it takes to have a healthy baby – not on what it might take for your child to experience better health throughout their life.
  • Of course, the science of epigenetics is relatively new. It will be many years before we will be able to make specific recommendations as to what your diet should be like during pregnancy and lactation if you wish to make beneficial modifications to your baby’s DNA.
  • However, you should be aware that what you eat during pregnancy & lactation may influence the health of your children – not just at the time of their birth – but throughout their life, and that a high calorie, “junk-food” diet or a fad weight loss diet just may not be your best choice.

*The agouti mice picture is by Randy Jirtle and Dana Dolinoy (E-mailed by author) [CC BY 3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons.

 

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.

Do Women Get Enough Omega-3 During Pregnancy?

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Should Pregnant Women Take Omega-3 Supplements?

Author: Dr. Stephen Chaney

 

  • omega-3 during pregnancyLong Chain Omega-3 Fatty Acids, Especially DHA, Are Essential For Normal Brain Development

Long chain omega-3 fatty acids, especially DHA, have been shown to be very important during pregnancy, especially during the third trimester when DHA accumulates in the fetal brain at a very high rate. It is during that third trimester that the fetus forms the majority of brain cells that they will have for an entire lifetime.

Inadequate intake of long chain omega-3 during pregnancy and lactation has been shown to be associated with poor neurodevelopmental outcomes. These include poor developmental milestones, problem solving, language development and increased hyperactivity in the children (Coletta et al, Reviews in Obstetrics & Gynecology, 3, 163-171, 2010).

  • The Current Recommendation is 200 mg DHA/day During Pregnancy & Lactation.

In order to support brain development in the fetus, some experts have recommend intake of 300 mg per day of DHA during pregnancy. The best dietary sources of long chain omega-3 fatty acids such as DHA are fish and fish oil supplements. However, because of concerns about seafood contamination with heavy metals and PCBs (both of which are neurotoxins), the FDA recommended in 2004 that pregnant women limit seafood consumption to two servings a week, which amounts to about 200 mg/day of DHA – and this has been subsequently adopted by the American College of Obstetricians and Gynecologists and the European Union as the amount of DHA recommended during pregnancy and lactation (Coletta et al, Reviews in Obstetrics & Gynecology, 3, 163-171, 2010).

Even that recommendation for DHA from seafood could be overly generous. A recent study using the EPA risk assessment protocol concluded that some farmed salmon were so contaminated with PCBs that they should be eaten no more than once a year (Hites et al, Science, 303: 226-229, 2004).

  • Most Pregnant & Lactating Women In The US Are Probably Not Getting The Recommended Amount of DHA In Their Diet

Many pregnant women avoid seafood because of concerns about mercury and PCBs. Unfortunately, the other food sources of omega-3 fatty acids in the American diet, even many omega-3 fortified foods and supplements, are primarily composed of the short chain omega-3 fatty acid linolenic acid (also called alpha-linolenic acid or ALA), and only 1-4% of linolenic acid is converted to DHA in the body (Coletta et al, Reviews in Obstetrics & Gynecology, 3, 163-171, 2010).

Consequently, experts have been concerned for some time that American and Canadian women may not be getting enough DHA during pregnancy and lactation, but it was not clear how serious an issue this was.

Do Women Get Enough Omega-3 During Pregnancy?

women take enough dha omega-3 during pregnancyA group of scientists decided to test the adequacy of DHA intake by comparing DHA intake with the recommended 200 mg/day in a group of 600 pregnant and lactating women enrolled in the Alberta Pregnancy Outcomes and Nutrition study (Jia et al, Applied Physiology, Nutrition & Metabolism, 40: 1-8, 2015). The average age of the women in this study was 31.6. They were primarily Caucasian and married. 92% of them breastfed their infants. Most of them were taking a multivitamin or prenatal supplement on a daily basis. Approximately 1/3 of them were also taking a long chain omega-3 supplement.

The majority of women had completed college and had annual household incomes in excess of $100,000/year. In short, this was a very affluent, well-educated group of women. This is the kind of group one might consider most likely to be getting enough DHA from their diet.

DHA intake was based on 24 hour food recalls and supplement intake questionnaires collected in face-to-face interviews 2-3 times during pregnancy and again 3 months after delivery. The DHA content of the diet was determined from these data using well established methods.

The results were both dramatic and concerning.

  • Only 27% of pregnant women and only 25% of postpartum women who were breastfeeding met the recommendation of 200 mg of DHA/day. In short, nearly three-quarters of the women in the study were not getting enough (DHA) omega-3 during pregnancy and lactation.
  • When the women who were taking DHA-containing supplements were excluded from the data analysis, only 13% of pregnant and lactating women were getting enough DHA from their diet. In short, nearly 90% of the women relying on diet alone were not getting enough DHA.
  • Taking a DHA-containing supplement increased the likelihood of achieving the recommended 200 mg DHA/day by 10.6 fold during pregnancy and 11.1 fold during breastfeeding.
  • Not surprisingly, seafood, fish and seaweed products were the major contributors to the total dietary DHA intake.

The authors concluded “Our results suggest that the majority of participants in the cohort were not meeting the EU recommendations for DHA during pregnancy and lactation, but taking a supplement significantly improved the likelihood that they would meet the recommendations.”

 

The Bottom Line

  • Long chain omega-3 fatty acids, especially DHA, are essential for normal brain development. Inadequate DHA intake during pregnancy and lactation is associated with poor developmental milestones, problem solving, language development and increased hyperactivity in the children.
  • There is no established Daily Value for omega-3 fatty acids. However, the American College of Obstetricians and Gynecologists and the European Union recommend 200 mg DHA/day during pregnancy and lactation.
  • This recommendation is based partly on the amount of DHA needed for brain development and partly on the FDA warning that pregnant women should not consume more than 2 servings of fish/week due to heavy metal and PCB contamination.
  • This recommendation can be met by 1-2 six ounce servings/week of fish or a fish oil supplement containing 550 – 600 mg of omega-3 fatty acids.
  • Many pregnant women avoid fish because of concerns about contamination with heavy metals and PCBs, both of which are neurotoxins. Therefore, the major source of omega-3s in the American and Canadian diets are short chain omega-3 fatty acids that are only inefficiently (1-4%) converted to DHA.
  • Consequently, experts have been concerned for some time that American and Canadian women may not be getting enough DHA during pregnancy and lactation, but it was not clear how serious an issue this was.
  • A recent study done with a group of 600 women enrolled in the Alberta Pregnancy Outcomes and Nutrition study found that:
  • Only 27% of pregnant women and only 25% of postpartum women who were breastfeeding met the recommendation of 200 mg of DHA/day. In short, nearly three-quarters of the women in the study were not getting enough (DHA) omega-3 during pregnancy and lactation.
  • When the women who were taking DHA-containing supplements were excluded from the data analysis, only 13% of pregnant and lactating women were getting enough DHA from their diet. . In short, nearly 90% of the women relying on diet alone were not getting enough DHA.
  • Taking a DHA-containing supplement increased the likelihood of achieving the recommended 200 mg DHA/day by 10.6 fold during pregnancy and 11.1 fold during breastfeeding.
  • This was a very affluent, well-educated group of women. If any women anywhere are getting enough DHA during pregnancy and lactation, this should have been the group that was.
  • The authors concluded “Our results suggest that the majority of participants in the cohort were not meeting the EU recommendations for (DHA) omega-3 during pregnancy and lactation, but taking a supplement significantly improved the likelihood that they would meet the recommendations.”

 

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.

Food Ingredients To Avoid List

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Food Ingredients to Avoid Part 2: The Good, The Bad & The Ugly

Author: Dr. Stephen Chaney

 

food additivesIt is getting really hard to find a food or food supplement that doesn’t have any ingredients on the internet “naughty list”. The problem is that many of the internet warnings about food ingredients are what I call “urban nutrition myths”.  Want to know the truth about which additives should be on the  food ingredients to avoid list?

Last week I identified the top 25 food ingredients on the internet “naughty list” and told you which ones were actually “good” – OK for most people most of the time. This week I’m going to tell which ones are “bad” and which ones are truly “ugly”.

Food Ingredients to Avoid List?  The Bad

food ingredients to avoid badThe term “bad” for the food ingredients in this list is a bit of a misnomer. These are food ingredients that some people will want to avoid, but are perfectly OK for many people. In some cases, the type of food the ingredients are added to determines whether the ingredient is OK or should be avoided.  So, the following could possibly be on your food ingredients to avoid list.

Sodium Nitrate and Nitrite: This is a topic I have covered in a previous article titled “Nitric Oxide Benefits and Side Effects” . It is a perfect example of a food ingredient that can be “bad” in certain foods and “good” in others. Briefly:

  • When sodium nitrate and/or sodium nitrate are added to processed meats, they can combine with the amino acids from the meat in the intestine to form cancer-causing nitrosamines. As you might suspect, this is not a good thing.
  • On the other hand, when sodium nitrate or sodium nitrite are found in fruits are vegetables or combined with natural antioxidants such as vitamin C, they are converted to nitric oxide, which has a number of beneficial effects in the body. So when they are present in these foods or food supplements, they are actually beneficial.

Sugar & High Fructose Corn Syrup: As I said in my video “The Truth About Sugar” , there are no sugar villains and there are no sugar heroes. For example, high fructose corn syrup has been particularly vilified in recent years, but its chemical composition is not significantly different from honey and agave nectar, which are considered to be “good” sugars.

The problems associated with sugars of all types in the American diet are related to the amount of sugar in our diet (too much) and the kinds of foods they are found in. Let’s focus on that last one for a minute.

  • When sugars are consumed as a part of foods that are rich in fiber and/or protein they have much less of an effect on blood sugar levels (a lower glycemic index) than when they are consumed in sodas, juices and highly processed foods. That’s important because the bad health consequences of sugars are primarily caused by foods that lead to high blood sugar levels. See, for example, my article “Can Soft Drinks Cause Heart Disease?” .
  • Consequently, we should be focusing on the glycemic index (the effect on blood sugar levels) of the foods we eat rather than obsessing about the amount or kinds of sugar on the label.

MSG: MSG, or monosodium glutamate, is a particularly interesting case. MSG is the sodium salt of the amino acid glutamate.

Glutamate is a neurotransmitter.

  • When MSG is used as a flavor enhancer in foods with a low protein content, the glutamate is very rapidly taken up by the brain and can overstimulate some neurons.
  • For most people this is no problem, but a small number of people experience what used to be called “Chinese Restaurant Syndrome” due to the large amounts of MSG used in some Chinese foods.
  • The common symptoms associated with “Chinese Restaurant Syndrome” are headache, sweating, skin flushing, nausea & fatigue. Allergic reactions to MSG can even be life threatening in some individuals.

Glutamate is also found in every protein we eat. Consequently, we create lots of MSG in our intestine every time we eat and digest protein. In this situation it is no more harmful than any other amino acid in the proteins we eat.

  • The most logical explanation for this phenomenon is that when all of the amino acids are in our bloodstream simultaneously they compete with glutamate for uptake into the brain. This slows the entry of glutamate into the brain and prevents overstimulation of neurons.

The bottom line is that MSG as a flavor enhancer is harmless for most people, but problematic for some. MSG as a component of hydrolyzed vegetable protein or sodium caseinate is harmless because it is in balance with the other naturally occurring amino acids. Some websites claim that MSG is found in maltodextrin and citric acid. It is not.

Salt (Sodium): I could, and probably should, write a whole article on sodium intake. Suffice it to say that 1) most of us consume too much sodium, 2) most of that sodium is hidden in the foods we eat rather than added at the table, and 3) some people are more sensitive to the bad effects of sodium than others.

Refined Grains: Again, this could be a whole article. Suffice it to say that 1) whole grains are better than refined grains and 2) most of us would benefit from eating fewer grains in any form and more fruits and vegetables in their place.

Food Ingredients to Avoid List: The Ugly

Finally, there are some food ingredients that most experts (except for those in the food industry) agree should be avoided. I call them the dirty dozen. All should be on everyone’s food ingredients to avoid list.  They are:

food ingredients to avoid ugly

  • Trans fats (also known as partially hydrogenated vegetable oils).
  • Aspartame
  • Acesulfame-K
  • Sucralose
  • Artificial colors
  • Artificial flavors
  • BHA & BHT
  • Propyl gallate
  • Sodium and potassium benzoate
  • Potassium bromate
  • Potassium sorbate
  • Polysorbate 80

 

The Bottom Line

If you were to believe everything you read on the internet about food ingredients that you should avoid, you could end up spending most of your day reading food labels and still find very few foods that you could eat. Some of those warnings are true, some are partially true, and some are mostly myths.

To help you determine which to place on your food ingredients to avoid list,  I have identified the top 25 food ingredient warnings and have divided them into the good, the bad and the ugly.

  • The “good” are those food ingredients that are perfectly OK for most people, most of the time. Here are some examples (see the article above for a full explanation).
  • Soy: The supposed dangers of soy have been disproven by numerous clinical studies, but the myths persist. I do recommend that you choose non-GMO soy protein.
  • GMO: GMO foods and proteins are a concern but purified food ingredients obtained from GMO foods pose no health risks. There are, however, possible environmental concerns due to the overuse of Roundup.
  • Carrageenan and Caramel Color: In this case it is contaminants rather than the food ingredients themselves that are the problem. As long as you choose a manufacturer who performs rigorous quality control tests on their ingredients, you need not be concerned about these ingredients.
  • Canola Oil, Maltodextrin and Soy lecithin: The supposed dangers of these food ingredients are myths. They are not backed up by credible clinical studies. However, they are generally derived from GMO foods, so there is a possible environmental concern.
  • The “bad” are the food ingredients that do pose a problem for some people, particularly when those ingredients are found in the wrong kinds of foods. However, those same ingredients are OK for many people when they are in the right foods.
  • Sodium nitrate and nitrite: Those ingredients are a concern when added to processed meats, but are actually healthy when found in fresh fruits and vegetables or combined with antioxidants such as vitamin C.
  • Sugar and High Fructose Corn Syrup: We definitely need to reduce the amount of sugar in our diet. However, when looking at individual foods we should focus more on glycemic index than on the amount or kind of sugar.
  • MSG: MSG is a concern for some individuals when used as a flavor enhancer in low protein foods. However, it poses no risk when it is present as a component of partially digested proteins such as hydrolyzed vegetable protein or sodium casseinate.
  • The “ugly” are those ingredients that most experts agree we should avoid. They include trans fats, artificial sweeteners, artificial colors, artificial flavors, artificial preservatives and a few others listed 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.

Food Ingredients To Avoid

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Food Ingredients to Avoid-Part 1: The Good, The Bad & The Ugly

Author: Dr. Stephen Chaney

 

I have been getting a lot of questions lately about food ingredient labels. That’s because in today’s internet world everyone is an “expert” wanting to be heard. Couple that with the fact that old news is boring, and we have a problem. All of these experts have to keep coming up with information that is novel and scary. It doesn’t need to be true – just novel and scary.

food ingredients to avoidThe warnings about which food ingredients to avoid are a perfect example. A few years ago it was pretty simple to know which ingredients to avoid. If you avoided foods with sugar, refined flour, trans fats and all that artificial stuff, you were OK. However, in recent years the list of additives to avoid keeps getting longer and longer.

It has reached the point where it is getting really hard to find a food or food supplement that doesn’t have any of the ingredients on the “naughty list”. You may even be wondering if there is anything besides organic fresh fruits and vegetables that you actually can eat. How did we get to this point?

The answer is obvious. All the internet “experts” needed something new to warn us about so they took molehills and turned them into mountains. They took food ingredients that might cause a few problems for a limited number of people and characterized them as ingredients that were dangerous for everyone. Their posts were picked up and repeated by other “experts” and pretty soon everyone thought they had to be true. The warnings about food ingredients became what I call “urban nutrition myths”.

It is time for a myth buster to come along and help you sort through all of the ingredient warnings so that you know which ones are true and which are myths. That’s something I enjoy doing. Let me be your guide.

Which Food Ingredients Should You Avoid?

My “research” for this article began by Googling “Food Ingredients to Avoid” to see what was on the internet. Starting from the top of the list that came up on Google, here are the articles I found:

Men’s Fitness: “The 9 Scariest Food Additives You Are Eating Right Now “ (http://www.mensfitness.com/nutrition/avoid-these-9-worst-food-ingredients)

Waking Times: “20 Ingredients to Memorize and Avoid In Any Food You Consume (http://www.wakingtimes.com/2013/03/04/20-ingredients-to-memorize-and-avoid-in-any-food-you-consume/)

Women’s Health: “7 Ingredients Nutritionists Always Avoid” (http://www.womenshealthmag.com/nutrition/avoid-these-ingredients)

Reader’s Digest: “4 Most Harmful Ingredients In Packaged Foods” (http://www.rd.com/health/diet-weight-loss/4-most-harmful-ingredients-in-packaged-foods/)

Huffington Post: “10 Of The Worst Toxic Food Ingredients” (http://www.huffingtonpost.ca/2013/04/17/worst-toxic-food-ingredients_n_3101043.html)

WebMD did not even weigh in on the issue of food ingredient warnings. Reader’s Digest and the Huffington Post included mostly the ingredient warnings that we have been hearing about for years. The other three articles included some of the newcomers to the ingredient warning list. By combining all 5 of those articles, I came up with 25 of the most frequently mentioned “dangerous” food ingredients to avoid and have divided them into 3 categories. I call them “The Good, The Bad and the Ugly”.

This week I will help you identify the “good ones” – those food ingredients that are on many of the internet “naughty lists”, but are actually OK for most people most of the time. Next week, I’ll be back with the bad and the ugly lists.

Food Ingredients: The Good

good food ingredientsI would be the first to admit the using the word “good” as a descriptor for food ingredients is a bit of a misnomer. The word “good” should really be reserved for organic fresh fruits and vegetables along with other whole, unprocessed foods. Of course, the problem is that most of us don’t eat enough of those foods, so we need to know which ingredients in the processed foods and food supplements we eat are OK.

The list of food ingredients that are perfectly OK for most of us would be a long one, so let me just mention a few that have inadvertently slipped onto the online “naughty lists” that you may have seen.

GMO: Let me be perfectly clear. I am no fan of GMO foods, but ingredients derived from GMO foods are a very different story. I have covered this topic in detail in my previous articles “Should GMO Labeling Be Required For All Food Ingredients?” (https://www.chaneyhealth.com/healthtips/gmo-labeling-required-food-ingredients/) & “Will Non-GMO Foods Be Less Nutritious?” (https://www.chaneyhealth.com/healthtips/will-non-gmo-foods-be-less-nutritious/) and my webinar “The Truth About Genetically Modified Foods” (https://www.chaneyhealth.com/healthtips/videos/), so let me just summarize the key points here.

  • GMO foods and proteins derived from GMO foods can be a problem because of food sensitivities to the modified proteins. That risk is real, but is difficult to quantify.
  • All other food ingredients derived from genetically modified foods contain no genetic information or proteins. They are chemically & biologically indistinguishable from the same ingredients derived from non-GMO foods. Consequently, there are no health risks associated with these food ingredients.
  • I am aware of the recent internet chatter about the WHO declaring that Roundup can cause cancer. What is missed in these discussions is that Roundup is also approved for use just prior to harvest for non-GMO foods such as wheat and beans. That means that some non-GMO foods are more likely to be contaminated with Roundup residues than are GMO foods.
  • That just leaves the environmental issue. Roundup does break down relatively quickly in the environment, but I do have concerns about spraying tons of the stuff on our crops every year. However, I must acknowledge that many of my scientific colleagues do not share this concern, and they are not all in bed with Monstanto.

Soy: This is another topic I have covered extensively in my previous articles such as “Soy and Breast Cancer Recurrence” (https://www.chaneyhealth.com/healthtips/soy-and-breast-cancer-recurrence/) & “Soy and Breast Cancer” (https://www.chaneyhealth.com/healthtips/soy-breast-cancer/) and my video “The Truth About Soy” (https://www.chaneyhealth.com/healthtips/videos/). Once again, I will just give a brief summary.

  • The myths that soy consumption causes breast cancer or any other cancer, lowers testosterone levels in men and interferes with thyroid metabolism have been disproven by multiple clinical studies.
  • The idea that soy has to be fermented to be healthy is also a myth. Most soy products are processed in such a manner that the toxins in the soy bean are removed.
  • For ingredients made from soy such as soy lecithin, there are no health risks associated with sourcing them from GMO soy (see above). If you are consuming a soy protein product, however, I do recommend that you choose non-GMO soy.

CarrageenanCarrageenan: Carrageenan comes from seaweed and red algae. It has been used in foods for thousands of years because of its gelling properties. In the supplement world it is used to improve consistency and the disintegration of tablets.

There is a lot to like about carrageenan. It is natural, organic and non-GMO. Why then has it become an internet villain in the food ingredient world? The problem is that most of the internet “experts” who are vilifying carrageenan are not distinguishing between carrageenan and its breakdown product poligeenan. Here are the facts:

  • In some animal studies poligeenan at very high doses has been shown to cause diarrhea, hemorrhaging & ulcerations of the colon and even colon cancer. Not all animal studies agree, but this does raise the possibility that high doses of poligeenan might cause the same effects in humans.
  • Food grade carrageenan contains <5% poligeenan and does not raise the same concerns.
  • Food grade carrageenan does not cause gastrointestinal problems in most animal studies. Nor has it been shown to cause cancer in any animal study.
  • The FDA, USDA and WHO have reviewed all available studies and have concluded that food grade carrageenan is safe.
  • The International Agency for Research on Cancer (IARC) has concluded that carrageenan does not cause cancer.

Caramel Color: I won’t go into detail here, but the argument is similar to carrageenan. It is a minor impurity of caramel coloring that is the concern. However, caramel coloring itself should not be a concern for products made by any reputable manufacturer that employs rigorous quality control tests on their ingredients.

Canola Oil: Canola oil is an excellent source of monounsaturated fats and polyunsaturated fats, especially the beneficial omega-3 polyunsaturated fats. In supplements it is primarily used as a source of healthy fats and to improve taste, aroma or texture. There are some legitimate concerns with canola oil, but they have been considerably overhyped. This is a perfect example of a molehill being turned into a mountain. Let’s look at the myths that are simply untrue and the facts that have been overhyped.

  • Myth #1: Canola oil contains the same toxins as the original rapeseed oil. Fact: The toxins found in rapeseed oil has been removed through conventional plant breeding. Canola oil is toxin free.
  • Myth #2: Canola oil is toxic in animal studies. Fact: When you look at those studies carefully they were either done with rapeseed oil or were done under conditions where almost any vegetable oil would have been problematic.
  • Fact #1: Canola oil is highly processed. That’s true, but so are most other vegetable oils. If you want a less processed oil, choose virgin olive oil. (Unfortunately, it is not found in many processed foods or food supplements – probably because of cost). Some experts recommend palm oil or coconut oil, but they have their own problems because of their high saturated fat content.
  • Fact #2: Most canola oil comes from GMO plants. That is true, but canola oil is a highly purified food ingredient. As described above, that means there are no health concerns from eating GMO canola oil, only a possible environmental concern.

Maltodextrin: Maltodextrin is a natural food ingredient made from enzymatically digesting starch. It is used as a stabilizer and thickener in foods. It is also combined with glucose and fructose in sports drinks to provide sustained energy.

  • Myth #1: The internet is filled with claims that maltodextrin causes gastrointestinal problems or that it is unsafe. There is very little evidence to back that up, and we need to consider those claims in light of the fact that we produce lots of maltodextrin in our intestines every day as we digest the starches in our diet.
  • Myth #2: “Maltodextrin is just another sugar. It is just another way for food manufacturers to hide the total amount of sugar in their products.” Maltodextrin is actually less sweet than most sugars. As described above, it is primarily added to foods for reasons other than to impart sweetness.
  • Fact: Most of the maltodextrin in the US does come from GMO corn. Once again, it is a highly purified food ingredient. As with canola oil that means there are no health concerns, only possible environmental concerns.

Just because these ingredients are on my “good list” doesn’t mean that they won’t cause problems for some people. Lots of people have food allergies. My dad, for example, was allergic to chocolate, which has to be one of the cruelest food allergies that someone could have. Sometimes food allergies can be quite severe. Just ask someone with severe peanut allergies what life can be like if they even come near a peanut.

My point is that any natural food or food ingredient can cause allergic reactions in some people. That doesn’t make them bad. It is just part of normal living.

Next week I will be back with “the bad and the ugly” food ingredients. Stay tuned.

 

The Bottom Line

If you were to believe everything you read on the internet about food ingredients that you should avoid, you could end up spending most of your day reading food labels and still find very few foods that you could eat. Some of those warnings are true, some are partially true, and some are mostly myths.

To help you sort through this confusing information I have identified the top 25 food ingredient warnings and have divided them into the good, the bad and the ugly. This week I covered the “good ones”.

The “good” are those food ingredients that are perfectly OK for most people, most of the time. Here are some examples (see the article above for a full explanation).

  • Soy: The supposed dangers of soy have been disproven by numerous clinical studies, but the myths persist. I do recommend that you choose non-GMO soy protein.
  • GMO: GMO foods and proteins are a concern, but purified food ingredients obtained from GMO foods pose no health risks. There are, however, possible environmental concerns due to the overuse of Roundup when those GMO foods were grown.
  • Carrageenan and Caramel Color: In this case it is contaminants rather than the food ingredients themselves that are the problem. As long as you choose a manufacturer who performs rigorous quality control tests on their ingredients, you need not be concerned about these ingredients.
  • Canola Oil, Maltodextrin and Soy lecithin: The supposed dangers of these food ingredients are myths. They are not backed up by credible clinical studies. However, they are generally derived from GMO foods, so there is a possible environmental concern.
  • Just because these food ingredients made my good list doesn’t mean they are OK for everyone. People can be allergic to certain food ingredients, just as they can be allergic to certain foods so for some, these can still be food ingredients to avoid.

 

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.

Soy and Breast Cancer

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soy and breast cancerThe Soy Controversy

Author: Dr. Stephen Chaney

 

 

Soy and breast cancer: the wars are heating up again. You may have seen the recent headlines saying: “Soy protein found to speed the growth of breast cancer!” “Eating soy may turn on genes linked to [breast] cancer growth!” “Women with breast cancer should avoid high soy diets!” It all sounds pretty scary.

If this is true, it is big news. In recent years the consensus in the scientific community has been that soy is not harmful for women with breast cancer, and that it might even be beneficial. However, some skeptics have never accepted that consensus view. Those skeptics are once again claiming that soy protein may be risky for women with breast cancer.

Let’s look at the study behind the recent headlines and see if it is compelling enough to challenge the prevailing consensus on the safety of soy for women with breast cancer.

Does Soy Protein Turn On Breast Cancer Growth Genes?

This study (Shike et al, Journal of the National Cancer Institute, Sep 4 2014, doi: 10.1093/jnci/dju 189) looked at 140 women (average age 56) with invasive breast cancer. They were randomly divided into two groups of 70 and either given soy protein or a placebo between the initial biopsy and the time that surgery was performed to remove the tumor (a period of 7 to 30 days). A second biopsy was obtained at the time of surgery.

The activity of a number of genes associated with breast cancer survival was measured in the two biopsy samples. The observation that made the headlines was:

  • For some of the women in the study the activity of several genes associated with breast cancer growth and survival was increased in the group consuming soy protein compared to the placebo group. The authors concluded: “These data raise concern that soy may exert a stimulatory effect on breast cancer in a subset of women.”

What Are The Limitations Of The Study?

The authors acknowledged the many limitations of the study, but the press has largely ignored them.

  • The increased activity of the cancer growth genes was only seen in 20% of the women studied. For 80% of the women studied soy protein consumption had no effect on the activity of genes associated with breast cancer growth and survival.
  • This effect was only seen for some of the genes associated with breast cancer growth and survival. Other breast cancer growth genes were not affected in any of the women enrolled in the study. The authors conceded that it was unknown whether these limited genetic changes would have any effect on tumor growth and survival.
  • There was no effect of soy consumption on actual tumor growth in any of the women studied.
  • This was a very short term study so it is not known whether these changes in gene expression would have continued if soy supplementation were continued for a longer period of time. There are numerous examples in the literature of initial changes in gene expression in response to a radical change in diet that disappear once the body becomes accustomed to the new diet.
  • There is absolutely no way of knowing if the observed changes in gene expression would actually affect clinical outcomes such as survival, response to chemotherapy or tumor recurrence.

Should Women With Breast Cancer Avoid Soy?breast cancer prevention

Even with all of the limitations listed above, if this were the only study to test the soy-breast cancer hypothesis, I and most other experts would probably be warning women with breast cancer to be very cautious about consuming soy.

However, as I discussed in a previous “Health Tips From the Professor” (https://www.chaneyhealth.com/healthtips/soy-and-breast-cancer-recurrence/) at least five clinical studies have been published on the effects of soy consumption on the recurrence of breast cancer in women who are breast cancer survivors, both in Chinese and American populations. The studies have shown either no effect of soy on breast cancer recurrence or a protective effect. None of them have shown any detrimental effects of soy consumption by breast cancer survivors.

A meta-analysis of all 5 studies was published last year (Chi et al, Asian Pac J Cancer Prev., 14: 2407-2412, 2013). This study combined the data from 11,206 breast cancer survivors in the US and China. Those with the highest soy consumption had a 23% decrease in recurrence and a 15% decrease in mortality from breast cancer.

Another meta-analysis of 18 clinical studies found that soy slightly decreases the risk of developing breast cancer in the first place (J Natl Cancer Inst, 98: 459-471, 2006). To date there is absolutely no clinical evidence that soy increases the risk of breast cancer.

The Bottom Line

What does this mean for you if you are a woman with breast cancer, a breast cancer survivor or someone who is concerned about your risk of developing breast cancer?

  1. The study that has generated the recent headlines has so many limitations that I would not recommend any changes in soy consumption at present. It raises an interesting hypothesis that requires further study and validation. If this hypothesis holds up it may result in changes in dietary recommendations for a very small subset of women with invasive breast cancer.
  1. There are many reasons to include soy protein foods as part of a healthy diet. Soy foods are one of the highest quality vegetable protein sources and provide a great alternative to many of the high fat, high cholesterol animal proteins in the American diet.
  1. I personally feel that these studies are clear cut enough that women who are concerned about their breast cancer risk, women with breast cancer, and breast cancer survivors no longer need to fear soy protein as part of a healthy diet.
  1. The responsible websites agree with this assessment. For example, WebMD and the American Institute for Cancer Research (AICR) both say that breast cancer survivors need no longer worry about eating moderate amounts of soy foods.
  1. The irresponsible websites (I won’t name names, but you know who they are) are still warning breast cancer survivors to avoid soy completely. They are citing the latest study, with all of its limitations, as proof that they were right all along. As a scientist I really have a problem with people who are unwilling to change their opinions in the face of overwhelming scientific evidence to the contrary.
  1. Finally, I want to emphasize that the published studies merely show that soy does not increase the risk of breast cancer and is safe to use for breast cancer survivors. None of those studies suggest that soy is an effective treatment for breast cancer. The protective effects of soy are modest at best. If you have breast cancer, consult with your physician about the best treatment options for you.

 

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.

Is Omega-3 Uptake Gender Specific?

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Do We Need To Reexamine Everything We Thought We Knew About Omega-3s?

Author: Dr. Stephen Chaney

is omega-3 uptake gender specific

Some of you may remember the book from a few years ago titled “Men are from Mars, Women are from Venus”. The book proposed that men and women communicate differently (Who would have guessed?), and understanding that fact would help husbands and wives communicate with each other more effectively. I know that some people complained that it was an overly simplistic viewpoint, but I know it sure helped me communicate more effectively with my wife.

I came across a very interesting article recently that suggested the omega-3 fatty acid EPA might be metabolized and utilized differently by men and women. You might say that the statement “Men are from Mars, Women are from Venus” applies to omega-3 utilization as well.

The Science Behind the Study

Now that I’ve captured your interest, perhaps I should fill in a few details. We have known for years that the long chain omega-3 fatty acids EPA and DHA appear to be beneficial at reducing the risk of heart disease. There are several mechanisms for that protective effect:

  1. Omega-3s reduce the stickiness of platelets so that platelet aggregation, a fancy name for blood clotting, occurs less readily. Of course, we want our blood to clot when we cut ourselves, but we don’t want it to clot inside our arteries, because that is the very process that can lead to heart attacks and stroke.
  1. Omega-3s lower triglycerides and reduce inflammation, two important risk factors for heart disease.
  1. Omega-3s help keep the walls of our blood vessels elastic, which enhances blood flow and reduces the risk of hypertension.

However, for any of those things to occur, the omega-3 fatty acids must first be incorporated into our cell membranes. Thus, it is not just how much omega-3s we get in our diet that is important. We need to know how many of those omega-3s are actually incorporated into our membranes.

What if the efficiency of omega-3 uptake into cellular membranes were different for men and women? That would change everything. It would affect the design of omega-3 clinical studies. It would affect omega-3 dietary recommendations for men and women. The implications of gender-specific uptake of omega-3s would be far reaching.

Is Omega-3 Uptake Gender Specific?omega-3

The authors of this week’s study (Pipingas et al., Nutrients, 6, 1956-1970, 2014) hypothesized that efficiency of omega-3 uptake might differ in men and women. They enrolled 160 participants in the study (47% male and 53& female) with an average age of 59 years. The study excluded anybody with pre-existing diabetes or heart disease and anybody who was significantly overweight. The study also excluded anyone taking drugs that might mask the effects of the omega-3 fatty acids and anybody who had previously consumed fish oil supplements or more than two servings of seafood per week.

This was a complex study. In this review I will focus only on the portion of the study relevant to the gender specificity of omega-3 uptake. For that portion of the study, both male and female participants were divided into three groups. The first group received 3 gm of fish oil (240 mg EPA and 240 mg DHA); the second group received 6 gm of fish oil (480 mg EPA and 480 mg of DHA); and the third group received sunflower seed oil as a placebo. The study lasted 16 weeks, and the incorporation of omega-3 fatty acids into red blood cell membranes was measured at the beginning of the study and at the end of 16 weeks.

When they looked at men and women combined, they found:

  • A dose specific increase in EPA incorporation into red cell membranes compared to placebo. That simply means the amount of EPA that ended up in the red blood cell membrane was greater when the participants consumed 6 gm of fish oil than when they consumed 3 gm of fish oil.
  • Very little incorporation of DHA into red blood cell membranes was seen at either dose. This was not unexpected. Previous studies have shown that EPA is preferentially incorporated into red cell membranes. Other tissues, such a neural tissue, preferentially incorporate DHA into their membranes.

When they looked at men and women separately, they found:

  • The efficiency of EPA incorporation into red cell membranes compared to placebo was greater for women than for men. In women increased EPA uptake into red cell membranes was seen with both 3 gm and 6 gm of fish oil. Whereas, with men increased EPA incorporation into red cell membranes was only seen at with 6 gm of fish oil.

What Is The Significance Of These Observations?

The authors concluded “This is an important area for future research because dietary recommendations around long chain omega-3 polyunsaturated fatty acid intake may need to be gender specific.”

However, there are a number of weaknesses of this study:

  1. It was a very small study. Obviously, this study needs to be repeated with a much larger cohort of men and women.
  1. This study was just looking at incorporation of omega-3s into red cell membranes. We don’t yet know whether the specificity of omega-3 uptake will be the same for other tissues. Nor do we know whether there will be gender specificity in the biological effects of omega-3s.
  1. Most importantly, not all previous studies have reported the same gender specificity in omega-3 uptake seen in this study.

So what does this mean for you? Should men be getting more omega-3 fatty acids in their diet than women, as the authors suggested? That is an intriguing idea, but based on the weaknesses I described above, I think it’s premature to make this kind of recommendation until these results have been confirmed by larger studies.

The Bottom Line

  1. A recent study has suggested that women may be more efficient at incorporating the omega-3 fatty acids EPA into their cellular membranes than men. The authors of the study concluded that “…dietary recommendations around long chain omega-3 polyunsaturated fatty acid intake may need to be gender specific.”
  1. However, the study has a number of weaknesses:
  • It was a very small study. Obviously, it needs to be repeated with a much larger cohort of men and women.
  • This study was just looking at incorporation of omega-3s into red cell membranes. We don’t yet know whether the specificity of omega-3 uptake will be the same for other tissues. Nor do we know whether there will be gender specificity in the biological effects of omega-3s.
  • Most importantly, not all previous studies have reported the same gender specificity in omega-3 uptake seen in this study.
  1. The idea that men and women may differ in their needs for omega-3 fatty acids is intriguing, but based on the weaknesses described above, it is premature to make this kind of recommendation until the results of the current study have been confirmed by larger studies.

 

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.

Best Diet For Weight Loss

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The Diet Wars Heat Up Again

Author: Dr. Stephen Chaney

best diet for weight loss

What is the best diet for weight loss? One week the headlines say that low-carbohydrate diets are better. The next week it’s low-fat diets that are better. There is even the occasional headline proclaiming that it doesn’t matter which diet you follow as long as you control your calories. It is no wonder that you are confused.

It is unusual, however, to have conflicting headlines within the same week, but that is exactly what happened last week. Let me take you behind the headlines to the actual clinical studies and help you sort through the conflicting headlines.

Are Low-Carbohydrate Diets Best For Weight Loss?

The manuscript behind this headline was published September 2nd in the Annals of Internal Medicine (Bazzano et al, Annals of Internal Medicine, 161: 309-318, 2014). This study was designed to determine which was the best diet for weight loss, low carb diet or low fat diet. The study recruited 148 overweight participants (mean age, 46.8, 88% female, 51% black) and randomly assigned them to either a low-fat diet or low-carbohydrate diet.

The participants on the low-fat diet were instructed to consume <30% of their calories from fat, while the participants on the low-carbohydrate diet were told to limit carbohydrates to <40 g/day. Neither group was told to limit calories. They met with a dietitian 10 times during the 12-month study and received information on dietary fiber (target = 25 g/day) and healthy fats (target = <7% saturated fat and little or no trans fats).

At the end of 12 months the low-carbohydrate diet resulted in significantly greater…

  • Weight loss (7.7 pounds)…
  • Decrease in triglyceride levels…
  • Increase in HDL cholesterol…
  • Decrease in the ratio of total to HDL Cholesterol…

…than the low-fat diet. In short, the results suggested that the low-carbohydrate diet was not only better than the low-fat diet for weight loss, but that it was also more effective in reducing risk factors for cardiovascular disease.

Case closed, you might be tempted to say. The low carb diet is the best the diet for weight loss. But there have been lots of other studies that have come to the opposite conclusion. So we have to ask the question: “Is this study significantly better than all of the studies that have failed to find any difference between the low-fat and low-carbohydrate diets with respect to weight loss and cardiovascular risk?”

What Are The Strengths & Weaknesses Of the Study?

Strengths of the Study: This was a very well designed study. In particular:

  • Dietitians met with the participants at multiple times during the program to assure adherence to the diet, which was very good.
  • The study utilized multiple dietary recalls, both during the week and on weekends.
  • The study had a diverse population.

Weaknesses of the Study:

  1. The study did not control calories. In fact, the caloric intake was ~160 calories/day greater for the low-fat group than the low-carbohydrate group for at least the first 6 months of the study. low carb dietThat alone would be enough to account for the 7.7 pounds difference in weight loss.The reason for the higher caloric intake of low-fat group is not known. It could be due to the lower palatability of the low-carbohydrate diet. Alternatively, it could be due to the lower satiety of the low-fat diet. It was low in both fat and protein, both of which contribute to satiety (the feeling of fullness after we eat).
  2. The study did not specify the type of carbohydrates consumed. The dietitians instructed the participants on the type of fat they should be eating, but not the type of carbohydrate. That was a significant omission. Diets high in sugars and refined carbohydrates provide less satiety and adversely affect cardiovascular risk factors compared to diets where the carbohydrate comes primarily from fresh fruits, vegetables and legumes.
  3. The study did not control protein intake. In fact, the low-fat group consumed significantly less protein than the low-carbohydrate group. As I pointed out in a previous “Health Tips From the Professor” High Protein Diets and Weight Loss , higher protein intakes are essential for maintaining muscle mass during weight loss. That is important because loss of muscle mass can decrease metabolic rate (the rate at which we burn calories 24 hours a day – even at rest).

The amount of protein consumed by the low-carbohydrate group was close to the amount shown to maintain muscle mass during weight loss, while the amount of protein consumed by the low-fat group was close to the amount associated with loss of muscle mass during weight loss. That was reflected in the results. The low-fat group lost muscle mass while the low carbohydrate group actually gained muscle mass. The resulting difference in muscle probably meant that the low-carbohydrate group was burning more calories on a daily basis than the low-fat group.

In short, this is a good study, but it has important flaws. It is not a game changer.

Do Low-Carbohydrate & Low-Fat Diets Result In Identical Weight Loss?

The study behind this headline was published in the September 3rd edition of the Journal of the American Medical Association (Johnson et al, JAMA, 312: 923-933, 2014). This study was a meta-analysis that combined the results of 48 studies with 7286 participants. When the authors combined the data from all of the published studies there was no difference in weight loss for the low-fat and low-carbohydrate diets over a one or two year period.

The strength of the study is that it combines the results of multiple studies. That increases the statistical power of the observations and smoothes over the effect of outlier studies, such as the one described above. This is the study I would trust.

What Do The Experts Say?

Dr. Walter Willett, Chair of the Department of Nutrition at the Harvard School of Public Health was best diet for weight lossquoted as saying: “…some people [would] do well on either diet. The key issue for each person is finding a way of eating that is healthy and can be maintained for the long term.”

Dr. Bradley Johnson (the author of the meta-analysis) was quoted as saying: “The take home message is that people should choose a diet they can adhere to…”

The Bottom Line

1)  Ignore the recent headlines suggesting that low-carbohydrate diets may be more effective than low-fat diets for weight loss. When you control for calories and protein intake there is no difference between the two diets with respect to long term weight loss.

2)  You can also ignore the headlines telling you that low-carbohydrate diets are better for cardiovascular health. You don’t need to avoid carbohydrates to have a healthy heart. You just need to make healthy carbohydrate choices – fruits, vegetables, legumes and whole grains instead of refined flour products and sugary junk food.

3)  Experts will tell you that the best diet is a healthy diet that you can stick with long term.

4)  My personal recommendations are to avoid extremes (either low-fat or low-carbohydrate). Instead:

  • Aim for moderate amounts of healthy fats and healthy carbohydrates.
  • Don’t ignore protein. Make sure you get enough protein to maintain your muscle mass.
  • Control calories by reducing portion sizes and choosing healthy snacks.

 

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.

Is There Hope for Alzheimer’s

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Preventing Cognitive Decline As We Age

Author: Dr. Stephen Chaney

 alzheimer's

As we age nothing is more terrifying than the word Alzheimer’s. For most of us the ultimate irony would be to spend a lifetime taking good care of our body, only to lose our mind. From time to time there are encouraging reports about the potential of low fat diets, diets rich in fruits and vegetables, B vitamins, omega-3 fatty acids, various herbs, and other natural approaches that might slow cognitive decline as we age.

Inevitably, it seems, those hopes are dashed by subsequent meta-analyses supposedly showing that each of those approaches is worthless. That wouldn’t be so bad if there were effective medications to slow cognitive decline and prevent Alzheimer’s, but there aren’t. The Alzheimer’s drugs on the market today simply have not been shown to be effective.

But, what if all of these studies were missing the mark by focusing on individual interventions? Perhaps we should be focusing a holistic approach instead.

 

The Power of Holistic Approaches

One of the examples of the power of a holistic approach that I love to use, because it really made an impression on me as a young scientist, occurred at an International Cancer Symposium I attended more than 30 years ago.

I attended a session in which an internally renowned expert was giving his talk on colon cancer. He said, “I can show you, unequivocally, that colon cancer risk is significantly decreased by a lifestyle that includes a high-fiber diet, a low-fat diet, adequate calcium, adequate B-vitamins, exercise and weight control. But I can’t show you that any one of them, by themselves, is effective.”

The question that came to me as I heard him speak was: “What’s the message that a responsible scientist or responsible health professional should be giving to their patients or the people that they’re advising?” You’ve heard experts saying: “Don’t worry about the fat” “Don’t worry about calcium.” “Don’t worry about B-vitamins.” “Don’t worry about fiber.” “None of them can be shown to decrease the risk of colon cancer.”

Is that the message that we should be giving people? Or should we really be saying what that doctor said many years ago – a lifestyle that includes all of those things significantly decreases the risk of colon cancer?

What about Alzheimer’s and cognitive decline? Could a holistic approach have an impact here as well?

 

Is There Hope For Alzheimer’s?

preventing-cognitive-declineA study performed by Dr. Miia Kivipelto and colleagues at the Karolinska Insitute in Sweden and the National Institute for Health and Welfare in Helsinki, Finland suggests that a holistic approach may, in fact, be able to slow cognitive decline in older people.

Previous studies had suggested that exercise, a good diet, socialization and memory training might slow cognitive decline in the elderly, but, like all other individual interventions, the benefits of these interventions were not reproducible. Dr. Kivipelto and colleagues designed a clinical study that combined all of these interventions into a single holistic approach.

They started with 1,260 healthy adults aged 60-77 from Sweden and Finland and divided them into two groups. One group was enrolled in a holistic program involving exercise, a healthy diet, socialization and memory training. This group was closely monitored for compliance. The other group was just given general health advice – not unlike the advice you might expect to receive from your doctor.

Each group was given a memory test at the beginning of the study and a second memory test two years later. Both groups scored about the same on the first memory test. However, the group enrolled in the holistic program did considerably better on the second memory test than the control group who had just been given general health advice.

One of the lead investigators was quoted as saying: “These findings show that prevention is possible, and it may be good to start early [before the signs of cognitive decline become evident]. With so many negative trials of Alzheimer’s drugs reportedly lately, it’s good that we may have something that everyone can do now to lower their risk [of cognitive decline].”

 

Limitations of the Study

There are two big caveats for this study.

1)     The study was too short to assess the effectiveness of this approach at reducing Alzheimer’s. The investigators plan to continue the study for 7 years. They hope that enough participants will have developed Alzheimer’s by then so they can accurately assess whether this approach is as effective at preventing Alzheimer’s as it is at preventing cognitive decline.

2)     This study was recently presented at an Alzheimer’s Association International Conference. It has not yet undergone the rigorous peer review required for publication. Once the study has been published I will give you an update.

 

The Bottom Line

1)     It has been very difficult to prove that individual interventions, whether they are natural or pharmaceutical, are effective at preventing cognitive decline and the onset of Alzheimer’s as we age.

2)    However, a recent study suggests that a holistic approach that includes exercise, optimal nutrition, socialization and memory training may be effective at preventing cognitive decline in older adults.

3)     Based on previously published individual studies, optimal nutrition probably includes:

  • A diet low in fat, especially saturated fat and trans fats
  • A diet with lots of fresh fruits and vegetables
  • Extra B vitamins, especially with high risk populations
  • Extra omega-3 fatty acids

4)     Although not mentioned in this study, maintaining proper body weight is also an important part of a holistic approach to reducing the risk of cognitive decline. In a previous “Health Tips From the Professor” I shared data showing that obesity alone can cause a 3-fold increase in the risk of developing dementia.

5)    The take home message should not be that each of the natural interventions is ineffective at preventing cognitive decline as we age. Rather, the message should be that a holistic approach that combines all of the natural interventions may be effective at preventing cognitive decline.

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.

Nitric Oxide Benefits and Side Effects

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Reverse Heart Disease?reverse-heart-disease

Author: Dr. Stephen Chaney

 

Nitric oxide has had a meteoric rise from obscurity to fame in just a few short years. It’s an amazing story. After all, nitric oxide is a colorless, odorless gas. Who could have known it was destined for greatness? In this article, we will discuss nitric oxide benefits and side effects.

Its rise to fame started in the 1980’s when scientists from several universities discovered that nitric oxide was an important regulator of numerous physiological processes. Just a few years later in 1992 Science magazine named it “Molecule of the Year”, a very prestigious honor. And, in 1998 three of its co-discoverers received the Nobel Prize for their ground-breaking research.

The Benefits of Nitric Oxide

Proven Benefits

Perhaps the most important benefit of nitric oxide is its role in maintaining the health of the endothelial cells that form the inner lining of our blood vessels. Nitric oxide reduces:

  • Platelet aggregation
  • Damage & inflammation of the endothelial cells
  • Oxidation of LDL cholesterol
  • Growth of smooth muscle cells.

This is important because these are the very physiological processes that, if left unchecked, can lead to atherosclerosis and disease of the cardiovascular system (Davignon and Ganz, Circulation, 109: 1127-1132, 2004; Tousoulis et al, Current Vascular Pharmacology, 10: 4-18, 2012).

cardiovascular-system

However, the effect of nitric oxide that has gotten the most attention is its ability to relax the smooth muscle cells that surround our blood vessels. That leads to increased blood flow, which in turn decreases blood pressure, relieves angina, and even prevents erectile dysfunction (Davignon and Ganz, Circulation, 109: 1127-1132, 2004; Tousoulis et al, Current Vascular Pharmacology, 10: 4-18, 2012).

Possible Benefits

Many people with atherosclerosis, diabetes and hypertension (high blood pressure) have low nitric oxide levels. It’s not known whether this is a cause or a result of these diseases, but low nitric oxide levels certainly could contribute to the progression and health consequences of all three diseases. We already know that increasing nitric oxide levels can reduce high blood pressure. It is not yet known whether increasing nitric oxide levels could reduce or reverse heart disease and the effects of diabetes, but this is an area of active research.

Nitric oxide is a neurotransmitter and is thought to play a critical role in memory and learning. It also plays a critical role in immune function. In addition, it enhances the metabolic activity of mitochondria, which could enhance cellular metabolism. The physiological significance of these observations is unknown, but this is another area of active research

Finally, because nitric oxide stimulates blood flow, which should increase oxygen and nutrient delivery to active muscle, it has been suggested that nitric oxide supplements would improve sports performance. The results of clinical studies to test this hypothesis have been mixed. The latest research suggests that nitric oxide supplements may enhance performance in untrained or moderately trained subjects, but not in highly trained subjects (Bescoe et al, Sports Medicine, 42: 99-117, 2012). At last, a sports supplement for the common man!

Drugs That Affect Nitric Oxide Levels

Because nitric oxide has such powerful physiological effects, the pharmaceutical industry has been busy creating drugs that either increase nitric oxide levels or increase the biological effectiveness of nitric oxide. For example, these include drugs to treat angina, hypertension, pulmonary hypertension and erectile dysfunction.

These drugs are generally effective, but have some drawbacks, namely:

  • They have numerous side effects. For example, just listen to the Viagra or Cialis ads on TV.
  • Some of them lose their biological effectiveness over time, especially the angina medications.

Natural Approaches for Increasing Nitric Oxide Levels

nitratesThere are two natural pathways for generating nitric oxide in the body.

1)     The first pathway is an enzymatic process that oxidizes a nitrogen atom in the amino acid arginine to nitric oxide.

2)     The second pathway is a non-enzymatic process in which naturally occurring nitrates and nitrites are reduced to nitric oxide either by bacteria in the mouth and intestine, or by naturally occurring antioxidants.

Arginine is found in proteins. The best protein sources of arginine are red meat, soy, crustaceans (crab, shrimp & lobster), nuts, spinach and lentils. In addition, you can find arginine supplements and arginine-enriched protein supplements.

The best natural sources of nitrates and nitrites are vegetables, especially spinach, beet root and arugula followed by green leafy vegetable and root vegetables in general. Vegetables provide about 80% of the nitrates and nitrites in the American diet.

Nitrates and nitrites do not appear to have the side effects of the nitic oxide producing drugs. This is probably because their effects on raising nitric oxide levels are slower and more modest, and they do not accumulate in the body.

Interestingly, conventionally grown vegetables are higher in nitrates than organically grown vegetables because of the use of inorganic, nitrate-containing fertilizers. However, that doesn’t mean that I recommend conventionally grown produce over organic produce. In last week’s “Health Tips From the Professor”, I reported that conventionally grown produce is 4-fold higher in pesticides.

Red meat and processed meats are also a minor source of nitrates and nitrites in the American diet because nitrates and nitrites are used as preservatives and coloring agents in those meats.

Are Nitrates and Nitrites Beneficial?

Until recently most of the focus has been on arginine as a natural source of nitric oxide. However, there are several lines of evidence suggesting that dietary sources of nitrates and nitrates can also provide the health benefits expected from nitric oxide.

For example, it has long been known that the DASH (Dietary Approaches to Stop Hypertension) diet is as effective as medications for lowering moderately elevated blood pressure. The DASH diet recommends 4-5 servings of vegetables per day, and recent studies have suggested that the nitrates found in those vegetables may play an important role in the blood pressure lowering effect of the DASH diet (Hord et al, American Journal of Clinical Nutrition, 90: 1-10, 2009; Lin et al, Journal of Nutrition and Metabolism, p 472396, 2012).

In addition, a recent meta-analysis of 16 clinical trials concluded that inorganic nitrate and beet root juice supplements lower blood pressure by modest amounts in healthy individuals (Siervo et al, Journal of Nutrition, 143: 818-826, 2013).

Are Nitrates and Nitrites Harmful?

There are two potential concerns around increasing dietary nitrate and nitrite intake.

1)     The one you may have heard the most about is the concern that dietary nitrates and nitrites might increase cancer risk. That turns out to be mainly associated with the nitrates and nitrites added to meats because, in the intestine, nitrites can combine with amino acids to form cancer causing nitrosamines.

That does not appear to be a problem with vegetables because vitamin C and other naturally occurring antioxidants in the vegetables prevent nitrosamine formation. There is no cancer risk in consuming more vegetables.

arginine

2)     The other concern is potential drug-nutrient interactions, especially drugs which also increase nitric oxide levels such as drugs for angina, hypertension, pulmonary hypertension and erectile dysfunction. This is because the combination of nitric oxide from nitrates in the diet and from the drugs has the potential to cause dangerously low blood pressure.

As a general precaution, if you are taking any medications I suggest consulting your doctor or pharmacist before increasing your dietary intake of nitrates and nitrites.

 

The Bottom Line

1)     Nitric oxide plays an important role in keeping the endothelial lining of your blood vessels healthy, which is thought to reduce the risk of atherosclerosis.

2)    Nitric oxide also relaxes the smooth muscle cells that surround our blood vessels. That increases blood flow and decreases blood pressure. The increased blood flow also decreases angina and erectile dysfunction.

3)    Nitric oxide also may increase blood flow to active muscle cells. This has been reported to increase exercise efficiency and sports performance. This effect of nitric oxide appears to primarily affect untrained and moderately trained athletes, not highly trained athletes.

4)    It has been suggested that nitric oxide may be useful for memory and learning, immune function, mitochondrial function and may reduce the risk of diabetes and heart disease. Research is currently going on to evaluate these hypotheses.

5)     There are two natural sources of nitric oxide:

  • The amino acid arginine from proteins and supplements
  • Nitrates and nitrites from vegetables such as spinach, beet root and arugula and from supplements.

6)     Foods (primarily vegetables) and supplements providing dietary nitrates have been shown to modestly lower blood pressure in healthy individuals. They are likely to provide the other benefits associated with nitric oxide as well, without the side effects associated with nitric oxide enhancing medications.

7)     Nitrates and nitrites from vegetables are unlikely to increase cancer risk because vitamin C and other antioxidants from the vegetables prevent the conversion of nitrates and nitrites to nitrosamines.

8)     If you are taking any medications, especially medications for angina, high blood pressure or erectile dysfunction, consult with your doctor or pharmacist before increasing your dietary nitrate intake.

9)     High blood pressure is a silent killer. You should never substitute dietary nitrates for blood pressure medication. Always consult with your physician first. They may be willing to work with you to lower the amount of medication if appropriate. Finally, even if you don’t have high blood pressure, you should monitor your blood pressure on a regular basis. High blood pressure can sneak up on you without you realizing it.

 

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.

Are Organic Foods Healthier?

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Organic Fruits & Vegetables

Author: Dr. Stephen Chaney

 fruits-vegetables

Are organic foods healthier for us than conventionally grown foods, specifically fruits and vegetables? The controversy about the benefits of organically raised produce continues. In fact, about the only thing that all sides agree on is that:

  • Organic foods have lower pesticide and herbicide residues and cause less environmental pollution.
  • Organic foods generally cost more.

But that is where all agreement ends.

  • Some experts argue that the pesticide levels on conventionally grown fruits and vegetables are within safe levels and that any risk from the pesticides is outweighed by the health benefits of the fruits and vegetables themselves.
  • Some studies have suggested that organic foods, fruits and vegetables, are healthier because they have higher antioxidant levels, while other studies have reported no nutritional differences between organic and conventionally grown fruits and vegetables.

Benefits of Organic Food?

The present study (Baranski et al, British Journal of Nutrition, doi: 10.1017/S0007114514001366) tried to overcome the shortcomings of many of the previously published reports.

To begin with this study was a meta-analysis that combined the results from 343 of the best designed previous studies to increase the statistical power of the analysis. In addition, the investigators utilized a type of statistical analysis that was superior to previously published studies. In short, it was a very good study. It does show some benefits of organic food.

organic-farms

The results were fairly clear cut:

  • Pesticide residues were four-fold lower in the organically raised produce than the conventionally raised produce. This result has been consistently seen in all of the previously published studies, and is probably the #1 reason that people choose organic produce. It is also one of the most agreed upon benefits of organic food.
  • Polyphenol antioxidant levels were significantly higher in the organically raised produce. The percent increase ranged from 19% to 69% depending on the polyphenolic compound tested. This increase has not been seen in all previously published studies, but would represent a side benefit if true.
  • Levels of the toxic metal cadmium were significantly less in the organically grown fruits and vegetables. The authors speculated that the cadmium found in conventionally grown produce came from the inorganic fertilizers that were used.

Should You Choose Organic Supplements?

natural-medicine

If organic foods are better for you than conventionally grown foods, does that mean that you should also choose organic supplements? While that idea sounds logical, the reality is actually more complex.

While organic foods clearly have less pesticides and toxic metals than conventionally grown foods, the level of those contaminants is not zero – even in foods with organic certification. The problem is that our environment is so polluted that no farm is contaminant free. A farmer can use the best organic practices, but if their groundwater is contaminated or pesticides from neighboring farms blow on to their farm, some of those toxic residues will end up in their “organic” crops.

 

So with supplements, “Organic” certification is not an absolute guarantee of purity. Instead you should insist on getting your supplements from a company with a very rigorous quality control program and a policy of rejecting any raw materials that contain contaminants of any kind.

The Bottom Line

1)     The latest study shows that pesticide residues are four-fold lower in the organically raised produce than the conventionally raised produce. This result has been consistently seen in all of the previously published studies, and is probably the #1 reason that people choose organic fruits and vegetables.

2)    Polyphenol antioxidant levels were significantly higher in the organically raised produce. The percent increase ranged from 19% to 69% depending on the polyphenolic compound tested. This increase has not been seen in all previously published studies, but would represent a side benefit if true.

3)    While one of the benefits of organic foods is they are less likely to be contaminated than conventionally grown foods, an organic certification is not a sufficient proof of purity when you are choosing supplements.You should insist on getting your supplements from a company with a very rigorous quality control program and a policy of rejecting any raw materials that contain contaminants of any kind.

 

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.

Health Tips From The Professor