Tag Archives: Supplementation

Anti-Aging Supplements | The Paleo Diet
Coenzyme Q10 (CoQ10) is one of the most widely consumed antioxidant supplements, but according to recently published research CoQ10 doesn’t function as commonly believed. Earlier this month, a team of researchers led by professor Siegfried Hekimi of McGill University (Canada) published their remarkable findings in Nature Communications.[1] Specifically, they demonstrated that CoQ10 doesn’t behave as antioxidant and, thus, shouldn’t be marketed as an anti-aging supplement.

This spells bad news for the rapidly growing CoQ10 market, but good news for people genuinely interested in improved health. A recently published market research report suggests the global CoQ10 market will nearly double by 2020, ballooning to an estimated $850 million. This money would be much better spent on healthy food, which provides plenty of antioxidants.

Professor Hekimi explained, “Our findings show that one of the major anti-aging antioxidant supplements used by people can’t possibly act as previously believed. Dietary supplements cost a lot of money to patients throughout the world—money that would be better spent on healthy food. What’s more, the hope for a quick fix makes people less motivated to undertake appropriate lifestyle changes.”[2]

CoQ10 is a lipid-like substance occurring naturally in all cells of the body. Cell mitochondria use CoQ10 to create energy from oxygen and various nutrients. In addition to this vital role, CoQ10 was also thought to behave as an antioxidant, hence being positioned as an anti-aging supplement.

The researchers experimented with a strain of mice unable to produce adequate amounts of endogenous CoQ10 and, therefore, requiring supplements. As expected, absent supplementation, those mice suffered severe illnesses and early death due to CoQ10’s vital role in energy production. Surprisingly, however, the scientists observed no signs of elevated oxidative damage when supplementation was suspended. This lack of damage, they determined, was not due to deployment of other antioxidant strategies. Eventually, they concluded that CoQ10 is not an antioxidant.

This study underscores a larger, more important issue with respect to supplements, particularly antioxidant supplements. Besides simply being ineffective, as per CoQ10, antioxidant supplements (or those marketed as such) can actually damage your health. Dr. Cordain has written extensively about the numerous randomized controlled trials and meta-analyses showing these products actually increase all-cause mortality. For example, a 2007 meta-analysis spanning 67 random controlled trials (232,606 participants) determined that antioxidant supplementation with vitamin E or vitamin A increases overall death rates.[3]

For most people, the only supplements Dr. Cordain recommends (if any) are fish oil and vitamin D. And, whereas the recently published study shows CoQ10 is not an antioxidant, you might wonder whether it’s a worthwhile supplement based on CoQ10’s role in energy production. This is a valid question, but the answer is very simple and straightforward. By consuming a healthy Paleo diet, your cells will have all the CoQ10 they need. Dr. Cordain further points out that meat, poultry, and fish are concentrated sources of natural CoQ10.

Supplementation is a dangerous game because nutrients can easily be consumed excessively and in the wrong proportions with respect to other nutrients. Whole foods don’t have this problem. That’s why the Paleo diet emphasizes food while largely discouraging supplements.

Christopher James Clark, B.B.A.
Nutritional Grail

Christopher James Clark | The Paleo Diet TeamChristopher James Clark, B.B.A. is an award-winning writer, consultant, and chef with specialized knowledge in nutritional science and healing cuisine. He has a Business Administration degree from the University of Michigan and formerly worked as a revenue management analyst for a Fortune 100 company. For the past decade-plus, he has been designing menus, recipes, and food concepts for restaurants and spas, coaching private clients, teaching cooking workshops worldwide, and managing the kitchen for a renowned Greek yoga resort. Clark is the author of the critically acclaimed, award-winning book, Nutritional Grail.



[1] Wang Y, et al. (Mar 2013). Mitochondrial function and lifespan of mice with controlled ubiquinone biosynthesis. Nature Communications, 6(6393).

[2] McGill University. (Mar 6, 2015). Popular antioxidant likely ineffective, study finds. ScienceDaily.

[3] Bjelakovic G, et al. (Feb 2007). Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: systematic review and meta-analysis. JAMA, 297(8).

Nutrient Deficiencies and Supplementation | The Paleo Diet

I was recently asked by a Natuopathic Doctor (ND) whether supplements should be prescribed to help patients achieve certain therapeutic effects that may not be achieved through diet alone. In regards to vitamin, mineral and nutritional supplements I believe that most people following a traditional western junk food diet or a vegetarian/vegan diet will ultimately become nutrient deficient or nutrient impaired. Over the course of years, decades and lifetimes, these nutrient impairments and deficiencies will promote increased morbidity (disease incidence) and mortality (death rates).

Clearly, overt nutrient deficiency diseases such as scurvy (lack of vitamin C), pellagra (lack of niacin or vitamin B3), and beriberi (lack of thiamine or vitamin B1) ultimately can be fatal. However, in the western world we rarely or never see these potentially fatal nutrient related diseases. What clinicians often see are nutrient insufficiencies that promote obesity, ill health and disease. In regards to health in the western world, it is probably more important to focus upon the foods that we should avoid (modern processed foods) than upon the foods that we should eat.

My point is that anyone consuming a contemporary “Paleo Diet” will never become deficient in these or any other nutrient. In fact, data from our laboratory indicates that modern diets based upon Stone Age hunter-gatherer food groups (fresh fruits, vegetables, grass produced meats, organ meats, fish, seafood, free ranging eggs, and nuts) are incredibly nutrient dense1, 2 and far surpass the DRI of governmental recommendations for the 13 nutrients most lacking in the US diet.1, 2 Accordingly, no supplementation is required of people who are adherent to modern diets which emulate the food groups our ancestors ate.

A few key caveats should be mentioned:

  1. Most westerners, particularly those living at northern latitudes, do not receive sufficient sunlight exposure required for our bodies to produce adequate blood concentrations of vitamin D. Hence, I recommend vitamin D3 supplementation (at least 2,000 IU or more daily) for people unable to get out into the sun on a regular basis.
  1. Our hunter-gatherer ancestors consumed the entire carcass (brains, liver, marrow, gonads, etc.) of the terrestrial and aquatic animals they killed — accordingly these foods are rich sources of long chain omega 3 fatty acids (EPA and DHA). If patients do not or have not consumed fatty fish (salmon, mackerel, sardines, and/or herring) regularly, then I recommend these people should supplement with fish oil.
  1. People who have practiced a vegetarian and/or vegan diet for long periods of time will certainly be deficient in a wide variety of nutrients.3 Accordingly, health care practitioners advising their patients should require a broad panel of blood parameters from a reliable laboratory and provide nutrient prescriptions based upon individual nutrient deficiencies or insufficiencies. However, the best clinical strategy is to prescribe a diet rich in these nutrients (ergo the Paleo Diet). Nutrient deficiencies or insufficiencies rapidly disappear when people stop consuming nutrient poor foods (refined sugars, refined grains, refined vegetable oils, salted foods, processed foods, whole grain cereals, refined cereals, high glycemic load carbohydrates and legumes). Hence, prescriptions of supplements by health care practitioners should typically involve the short term (months) and never the long term, once nutrient dense diets are adopted by your patients.


Loren Cordain, Ph.D., Professor Emeritus



1. Cordain L, Eaton SB, Sebastian A, et al. Origins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr. 2005;81(2):341-354.

2. Cordain L. The Nutritional Characteristics of a Contemporary Diet Based Upon Paleolithic Food Groups. JANA. 2002;5(3):15-24.

3. Cordain, L. “Vegetarianism Can Be Hazardous to Your Health.” The Paleo Answer: 7 Days to Lose Weight, Feel Great, Stay Young. Hoboken, NJ: John Wiley & Sons, 2012. 45-71. Print.

Selenium Supplementation and The Paleo Diet | The Paleo Diet

Last month the International Journal of Cancer published a study conducted by researchers from Newcastle University, the International Agency for Research on Cancer, and the Royal College of Surgeons in Ireland. The research team concluded that lower serum selenium levels are associated with increased risks for colorectal cancer and that people in Europe, on average, are at higher risk than those in North America.1 They estimate that Western Europeans average 80 mcg of selenium per liter of blood, compared to 110-170 for North Americans; they attribute this disparity to lower levels of selenium in European soils.

As colorectal cancer is the second leading cause of cancer related deaths in Europe (as well as in the US), this study has sparked interest in selenium supplementation. Newcastle University professor John Hesketh, one of the study’s researchers, commented, “We think this [study] provides a strong case for a Europe-wide study to investigate the impact of supplementing food with selenium.”2 Hesketh quickly points out, however, that too much selenium is toxic, which makes supplementation problematic. “The difficulty with selenium,” he explains, “is that it’s a very narrow window between levels that are sub-optimal and those that would be considered toxic.”3

So what exactly is selenium? Why is it so important? Are there strategies, short of supplementation, to ensure we’re getting optimal levels? Can the Paleo diet help? Selenium is an essential micronutrient that supports thyroid function and the immune system. The thyroid, in fact, contains more selenium per gram of tissue than any other organ.4 Selenium also acts as an antioxidant, working synergistically with vitamin E (which also acts as an antioxidant). Dr. Nicholas Ralston, one of the world’s leading selenium experts, explains that selenium also supports the formation of an elite family of enzymes. “These enzymes,” Ralston notes, “perform irreplaceable functions, including preventing and/or reversing oxidative damage, controlling essential events in cell signaling, maintaining metabolic pathway processes, controlling protein folding, and regulating thyroid hormone status.”5

Selenium Supplementation and The Paleo Diet | The Paleo Diet

As mentioned above, selenium is tricky because too much is actually counterproductive. According to the Institute of Medicine, the tolerable upper level for adults is 400 mcg/day.6 The FDA recommends 70 mcg/day, but some research suggests this amount is insufficient. Research conducted at the University of Buffalo’s Roswell Park Cancer Institute, for example, has established 200 mcg per day as the safest, most therapeutic amount for cancer prevention (specifically prostate, colon, and lung cancers).7

The great news is that with the Paleo diet, it’s relatively easy to consume 100 to 200 mcg/day of selenium. The best sources include mushrooms, eggs, seafood, poultry, seeds, and nuts. Brazil nuts are the most potent known source; a mere 10 grams (2 nuts) provides 192 mcg.

The chart above shows the selenium content of common Paleo foods. As you’ll see, there’s no need to spend extra cash on selenium supplements. For most people, a carefully planned Paleo diet provides plenty of selenium. And should you need a boost, 1 or 2 Brazil nuts daily can be thought of as superior quality, natural “supplements.”

Christopher James Clark, B.B.A.

Nutritional Grail

Christopher James Clark | The Paleo Diet TeamChristopher James Clark, B.B.A. is an award-winning writer, consultant, and chef with specialized knowledge in nutritional science and healing cuisine. He has a Business Administration degree from the University of Michigan and formerly worked as a revenue management analyst for a Fortune 100 company. For the past decade-plus, he has been designing menus, recipes, and food concepts for restaurants and spas, coaching private clients, teaching cooking workshops worldwide, and managing the kitchen for a renowned Greek yoga resort. Clark is the author of the critically acclaimed, award-winning book, Nutritional Grail.


[1] Hughes, DJ, et al. (March 2015). Selenium status is associated with colorectal cancer risk in the European prospective investigation of cancer and nutrition cohort. International Journal of Cancer, 136(5). Retrieved from //www.ncbi.nlm.nih.gov/pubmed/25042282

[2] Press release, University of Newcastle. (December 16, 2014). New findings in the link between selenium and cancer. Retrieved from //www.ncl.ac.uk/press.office/press.release/item/new-findings-in-the-link-between-selenium-and-cancer

[3] Ibid.

[4] Dickson, RC, and Tomlinson, RH. (May 1967). Selenium in blood and human tissues. Clinica Chimica Acta, 16(2). Retrieved from //www.ncbi.nlm.nih.gov/pubmed/4166400

[5] Ralston, N. (September 2011). Selenium’s Pivotal Roles in Relation to Mercury Exposure Risks. PROMOTING HEALTHY COMMUNITIES: Developing and Exploring Linkages Between Public Health Indicators, Exposure and Hazard Data. Environmental Protection Agency. Retrieved from //www.epa.gov/ncer/events/calendar/2011/sep26/abstracts.html

[6] Dietary Supplement Fact Sheet: Selenium, Office of Dietary Supplements, National Institutes of Health. Retrieved from Ods.od.nih.gov/factsheets/selenium/

[7] Reid, ME, et al. (March 2008). The nutritional prevention of cancer: 400 mcg per day selenium treatment. Nutrition and Cancer, 60(2). Retrieved from //www.ncbi.nlm.nih.gov/pubmed/18444146

Chopping Block | The Paleo Diet

Scientific Veracity and Documentation > Snake Oil Salesmen

To put it bluntly, in the words of a well-known author “money can make whores of us all.” It can destroy partnerships, marriages, families, friends and lives. This concept is nothing new and has been known to humanity since we left our egalitarian roles as hunter gatherers and became agriculturalists with stratified societies separated by haves-and-have-nots dating to at least 10,000 years ago. The modern Paleo Diet concept, despite its ancient origins, represents a mere drop in the bucket from an evolutionary standpoint when contrasted to other present-day diets. For contemporary people, the Paleo Diet idea began in 1985 with Boyd Eaton’s seminal publication in the New England Journal of Medicine.1 It gained a bit of traction in the non-scientific community with the publication of my book, The Paleo Diet, in 2002,2 but really became viral, starting in about 2009, with its recognition across the web and the subsequent  publication of hundreds of cookbooks and diet books on the topic.  As with any new concept or idea embraced by vast numbers of people worldwide, it was inevitable that money would raise its ugly head and become part of the Paleo Diet equation.

My original impetus to study the Paleo Diet concept had little to do with money, but rather to do with improving my own fitness and health. As a young man in my 30s I simply wanted to find a lifelong way of eating that would maximize my health and complement my daily exercise program. After reading Dr. Eaton’s revolutionary article1 in 1987, a light went off in my head that has only glowed stronger throughout my life. I have dedicated my life’s work and academic career to this concept and have tried to do it justice via the scientific method with which I was trained as a Bachelor’s, Master’s and Ph.D. student, and finally as a University Professor (Assistant, Associate and Full).  Accordingly, my original goals, as improbable as they may seem, were not to become  a widely known nutritional scientist, a bestselling author or a public speaker but rather only to discover a universal program of lifelong eating that could improve my personal health.

As I ventured forth in the world with this almost simplistic objective in mind, I met many scientists and lay people who shared my vision that evolution via natural selection was the driving force behind human diet. As I became more well versed in this powerful Darwinian concept, I soon realized these ideas were collectively important for improving the health and well being of all people on the planet. From that point on, I dedicated myself and my career to this Paleo Diet notion and began to publish scientific articles in peer review journals to substantiate this perspective. Eventually, my wife, Lorrie convinced me to write a popular book2 on the topic – Paleo went viral, and the rest is very recent history.

Unfortunately, money and greed have tarnished the simplicity and unadulterated vision of the Paleo Diet concept.

Conmen, Crooks, and Just Simple People

Before the Paleo Diet became a household name, less than a few hundred or perhaps a few thousand people worldwide were even aware of the idea. We used to correspond with one another via primitive “Listserves,” and got to know one another with our posts and ideas. The Paleo world was small then, and our concerns and worries revolved about scientific considerations; did pre-agricultural people eat cereal grains?  How much long chain omega 3 fatty acids did they consume, and what were the health effects? At the time, none of us could even imagine the vast network of Paleo Diet websites, blogs and even scientific articles that exist today.

My old friend, Robert Crayhon, a well-known and now deceased, popular health writer, said, “Always, let the data speak for itself.” I completely agree with Robert as his axiom is consistent with my lifelong academic and scientific training. I offer a second phrase for my friend Robert, “Charismatic individuals relying upon personal ideas should always be suspect.”

Herein lies some of the problems with the contemporary Paleo Diet movement. It has become a Medusa head of ideas spawned by just about anybody who can write a blog, a popular diet book or appear at a Paleo Diet conference. Although the medical and scientific literature is clearly imperfect, it still maintains a powerful modulating factor via peer review – meaning you just can’t say anything you want without input from your scientific peers and the editors of the journal wherein the manuscript was published.  The internet holds no such constraint; anybody can say anything without direct references to support their contentions – much less a critical review of both sides of any issue utilizing legitimate scientific references.

Specific Items

Mainstream Paleo Diet books are rife with nutritional myths their authors consider to be Paleo. Here’s a short list: salt, sea salt, honey, legumes, beans, nut flours, ghee, milk, goat milk, cheese, yogurt, kumis, coconut sugars, date and raisin sugars and molasses to name a few. Our writers and I have addressed many of these issues in prior blogs:

Sea Salt: Between the Devil and the Deep Blue Sea

Dairy: Milking It for All It’s Worth

Beans and Legumes: Are They Paleo?

What’s the Skinny on Ghee?

Honey: The Sticky Truth

With Paleo Diet enthusiasts growing exponentially over the last few years, and manufacturers and vendors catering to this new market niche, the Paleo Diet community has experienced a huge upswing in the dietary supplement market. While a large percentage of the Western population takes supplements, there is little to no need to supplement while following a Paleo Diet as I have previously pointed out in “Vitamin and Nutritional Supplements Increase Chronic Disease Morbidity (Incidence) and Mortality (Death).” Diets consisting of fresh fruits, vegetables, grass produced meats and poultry, eggs, fish, seafood, shellfish and nuts provide our species with all known nutritional requirements.

So Paleo Dieters, I would urge you caution when considering all supplement pushers, and always let the data speak for itself. Don’t necessarily believe charismatic Paleo Diet figures on the web or anywhere else, rather examine the science for yourself. Many claims of supplement necessity are nothing more than opinions which are pushed on us without the rigorous scientific backing needed to make nutritional and health judgments one way or another. These charismatic, non-scientific authors tell us this is how it is – believe me because I tell you it is so. Unfortunately, no randomized controlled trials of these authors’ sponsored products and their respective claims exist, much less meta analyses. I’ll ask you, could it be that your trusted Paleo author has succumbed to money, or do they just not know better?  Let the data speak for itself.


Loren Cordain, Ph.D., Professor Emeritus

Infertility | The Paleo Diet

One of the numerous benefits from eating “Paleo” or switching to a contemporary Paleo Diet if you eat in the standard American way is that you and your spouse/partner/ will greatly improve your chances for successful conception, pregnancy and a healthy baby. Here’s the information you may want to become acquainted with, particularly if you have avoided meats and fish and have previously focused upon whole grain cereals, legumes and processed foods in your diet.

If you fail to regularly eat animal foods (eggs, meat, fish and seafood) you will become deficient in vitamin B12 because plant food sources contain no B12. Further plant foods do not contain the specific types of vitamin B6 which are readily absorbable in the human gut. Accordingly, diets devoid of or lacking in animal proteins, will invariably be deficient in vitamin B12 and vitamin B6. Deficiencies or insufficiencies in these vitamins ultimately increase the level of homocysteine in our blood.

Elevated blood concentrations of homocysteine result primarily from too little vitamin B12. B6 and folate in our diets. When adequate stores of these B vitamins are present from nutritious foods in our diet (e.g. meats, fresh fruits and veggies), then our cells can defuse the poisonous effects of homocysteine and convert it into less toxic compounds. However, when B12 is lacking or deficient, as it almost always is in vegetarian and vegan diets, then homocysteine builds up in our bloodstream and literally infiltrates nearly every cell in our bodies.

Healthy egg cells in women and healthy sperm cells in men are absolutely essential requirements for getting pregnant, staying pregnant and producing normal embryos, vigorous infants and healthy children. Vitamin B12 deficiencies can elevate blood levels of homocysteine and cause numerous adverse health problems in pregnant women, their unborn fetuses and nursing infants. In addition to these unfavorable effects, a diet deficient or marginal in vitamins B12, B6 and folate can severely reduce your chances for successful fertilization and conception.

Infertility is a huge problem in both the U.S. and Europe and affects at least 6 million people in the U.S. or more importantly about 7.4 % of the reproductive age population. Many environmental and genetic factors may be involved. However, one thing is certain, as a couple, if you or your partner’s blood levels of vitamin B12, B6 and/or folate are low and your homocysteine is elevated, your chances for normal conception will be significantly reduced.

It is becoming increasingly evident that the low vitamin B12, B6 and folate status responsible for elevated homocysteine is toxic to both sperm and egg cells and may represent a major, previously un-recognized risk factor for infertility. More than 30 years ago, at least one group of researchers pointed out that Indian vegetarian men maintained lower vitamin B12 concentrations in their sperm than non-vegetarians and attributed these values to their vegetarian diet. Additionally, a number of these earlier studies hinted that vitamin B12 supplementation could improve sperm function and vigor and even boost male fertility.

If we fast forward to the 21st century, in the past five years similar nutritional patterns have been discovered in western populations. In a recent (2009) study of 172 men and 223 women who were unable to conceive, 36 % of men and 23 % of women had vitamin B12 deficiencies. Almost 40 % of the infertile men had abnormal semen that was directly related to their vitamin B12 deficiencies. Other recent studies in men show that low dietary folate and vitamin B12 are associated with high blood concentrations of homocysteine that likely underlie abnormal sperm function. On the flip side of the equation, women with compromised dietary B12 and folate intakes frequently have elevated blood levels of homocysteine which prevent them from becoming pregnant. We are not completely sure how these blood chemistry changes impede successful pregnancies in women, but tissue studies suggest that egg cells infiltrated by homocysteine and deficient in vitamin B12 and folate make them fragile and unable to continue with a normal pregnancy once fertilized.

Menstrual Problems caused by Vegetarian and Low Meat Diets

In addition to B vitamin deficiencies and elevated blood concentrations of homocysteine, vegetarian/low meat diets are frequently associated with menstrual problems known to affect fertility. A total of five studies have compared the incidence of menstrual irregularities between vegetarians and meat eaters. Four out of these five studies demonstrated significantly higher rates of menstrual complications in vegetarians. Let’s take a look at the only randomized controlled trial investigating vegetarian diets on menstrual health.

Dr. Pirke and researchers at the University of Trier in Germany randomly divided 18 young women with normal menstrual periods into either vegetarian or non-vegetarian diet groups. After six weeks, 7 of the 9 women assigned to the vegetarian diet stopped ovulating, whereas only a single woman in the meat eating group experienced this problem. The results of this experiment are shocking – within only six weeks of consuming a vegetarian diet, 78% of healthy, normally cycling women ceased ovulating. The take home message is this: if you are trying to get pregnant, one of your best strategies is to avoid vegetarian diets. While you’re at it, make sure your husband or partner does the same.

Zinc Deficiencies Impair Sperm Function

One of the most frequent nutritional shortcomings of vegetarian and vegan diets is that they fall short of recommended intakes for zinc. In the largest epidemiological study ever of vegetarians (The EPIC-Oxford Study) Dr. Davey and colleagues noted that vegans had “. . . the lowest intakes of retinol [vitamin A], vitamin B12, vitamin D, calcium and zinc. . .” when compared to meat and fish eaters. More importantly, with zinc it’s not just how much is present in your food, but how much is actually absorbed in your body. Although dietary zinc intakes in vegetarian diets sometimes appear to be adequate on paper – in the body they actually result in deficiencies because most of plant based zinc is bound to phytate and therefore unavailable for absorption. Phytate is an antinutrient found in whole grains, beans, soy and other legumes that prevents normal assimilation of many minerals. Laboratory experiments show that vegetarians only absorb about half as much zinc as meat eaters because zinc from animal food is much better assimilated than from plant foods.

Based upon this information, you might expect blood concentrations of zinc to be lower in vegetarians than meat eaters. Sometimes scientists have found this to be the case, but not always. The problem here has to do with where zinc ends up in our bodies after we ingest it. Most zinc finds its way into the interior of cells and does not accumulate in the liquid portion (plasma) of blood. Consequently, unless scientists examine zinc concentrations within cells, readings obtained in blood plasma frequently do not accurately reflect body stores of this essential mineral. In virtually every study of vegetarians which measured zinc levels inside various cells (red blood cells, hair cells and skin cells in saliva), plant based diets caused zinc deficiencies. In one study, 12 meat eating women were put on a lacto-ovo vegetarian diet, and after only 22 days Dr. Freeland-Graves and co-workers reported that zinc concentrations in the women’s salivary cells plunged by 27%. Similar results were described by Dr. Srikumar and colleagues from a longer term experiment in which 20 meat eating men and women adopted a lactovegetarian diet for an entire year. In this study, both hair cells and blood levels of zinc sharply declined and remained low throughout the 12 month experiment.

So, I’ve set the stage for zinc deficiencies and infertility problems. Because of their low zinc content and bioavailability, long term vegetarian diets almost always cause zinc deficiencies. Numerous epidemiological studies have shown that infertile men had poor sperm counts that were associated with reduced zinc levels in their semen. Virtually every well controlled experimental study ever conducted shows that men put on zinc deficient diets ended up with reduced sperm counts, impaired sperm health and often depressed blood testosterone levels. The good news is that these deleterious changes in male reproductive function can be reversed if zinc rich diets (e.g. The Paleo Diet) are consumed, or if zinc pills are supplemented. Dr. Steegers-Theunissen’s research group in the Netherlands showed dramatic improvements in the reproductive health of 103 sub-fertile men when zinc and folic acid were supplemented. Following the six month supplementation program, sperm counts increased significantly in the sub-fertile men while sperm abnormalities declined by 4 %. A similar study of 14 infertile men from India also indicated that zinc supplementation increased sperm health, sperm counts and shortly thereafter resulted in three successful conceptions by these men’s wives.

Whether you are a man or woman, if you want to sidestep infertility problems, the best advice I can give you is to abandon vegetarian/low meat diets and adopt the nutritional patterns that have sustained our hunter-gatherer ancestors for the past 2.6 million years. There are no known risks to adopting The Paleo Diet, and in fact, regular consumption of meat, seafood and fresh fruit and vegetables at the expense of cereals, dairy and processed foods will prevent vitamin B12 and folate deficiencies. In turn these essential vitamins will ensure that your blood levels of homocysteine will return to normal – effectively reducing your risk for cardiovascular, neurological, bone and reproductive diseases.


Loren Cordain, Ph.D., Professor Emeritus


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