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Balancing Migraine Pain with a Paleo Diet | The Paleo DIet

As a migraine sufferer, I was all too excited several years ago when the local hospital hosted an expert panel on migraine remedies which included diet. The 45 minute presentation covered the basic physiology, briefly mentioned chocolate and alcohol, and then spent the bulk of the time on medications – Aspirin, Excederin, Midrin, and Fioricet. During the Q&A I asked about omega-3 PUFAs since they are known to inhibit COX-2. One expert replied that she was unaware of any research on PUFAs or COX-2 for migraine. I appreciated her congenial reply, but sat down disappointed. Most of the medication identified did only one thing in the body – inhibit COX-2.

Let’s start at the beginning. Migraine is a complex condition with many subclasses including with aura (Classic,) without aura (Common,) chronic, retinal, and hemiplegic migraine.1-3

Whatever the name, for the 10-15% of Americans who suffer from them, migraines mean episodic, intense headaches, often with nausea and light and sound sensitivity. In all cases, it affects our quality of life and ability to work.4, 5

While medication remains the primary focus of migraine treatment, its use as the primary treatment has its own concerns. There’s now a class of chronic migraine called medication overuse headache (MOH) where overuse of pain medication can actually cause near daily headaches.6-8

This has led many to seek alternative treatments.

Diet may help. Migraineurs – a term that makes it sound like an exclusive club with a very low voluntary applicant pool – often cite dietary triggers for their migraines. The most common are alcohol, chocolate, cheese, caffeine, MSG and fasting.9 On the other side of the coin, dietary elements such as magnesium and omega-3 fatty acids may be therapeutic.10

Unsurprisingly, all of these dietary elements fit with a healthy, Paleo Diet lifestyle. So let’s take a look at the physiology of a few key elements of the Paleo Diet that can help you spend less time at the ”Migraineur Club House.”

MIGRAINE 101: DON’T GET HYPEREXCITED

There are many theories about the cause of migraines, but the most widely accepted is the neural hyperexcitability theory. Backed by recent MRI studies, it proposes neurons in the trigeminal-vascular region of the brain’s cortex become inappropriately activated, releasing a series of neurotransmitters that cause vasodilation, mast cell degranulation, increased permeability, platelet aggregation, inflammation, and ultimately pain.2, 9, 11-14 Recently, some suggest hyperexcitability is a result of a dysfunction in sodium-potassium transporters.15

For some, their migraine is preceded by a visual aura. This aura is caused by an initial depolarization of the neurons referred to as Cortical Spreading Depression.2, 15

That’s a very short summary of a very complex process. The take home message: an imbalance in excitation signals, neurotransmitters, and electrolytes may be at the root of your migraine pain. Dive in deeper with the references listed below.

POLYUNSATURATED FATTY ACIDS: MIND YOUR 3S AND 6S

While living out of the medicine cabinet may not be the best long term strategy, it’s important to point out that NSAIDs, such as ibuprofen, are very effective at reducing acute migraine pain.1, 4, 16 They do one thing – prevent the formation of molecules called prostaglandins by inhibiting a key enzyme called cyclooxygenase (COX).

So, it’s not surprising prostaglandins have been linked to migraine.1, 17-21 Simply injecting prostaglandin E2 (PGE2) into both healthy subjects and migraine sufferers was enough to cause migraine pain.22-25 The fact that  pain was immediate, indicates that PGE2 may actually be the direct cause of pain for sufferers.22

But how does this relate to diet?

Prostaglandins are created from the polyunsaturated fatty acids (PUFAs) we eat.1 Our bodies are not particular – they will use whatever type of PUFA is available. But we end up with very different prostaglandins depending on whether we consume more omega-3 or omega-6 PUFAs.26

The figure below shows the types of prostaglandins (and other eicosanoids) formed from arachidonic acid (omega-6) verses EPA (omega-3).26

Balancing Migraine Pain with a Paleo Diet | The Paleo Diet

PGE3 and PGI3 from omega-3 PUFAs may actually help prevent both the inflammation and electrolyte imbalance that causes migraines.15, 26, 27 In fact, they have anti-inflammatory benefits for many chronic illnesses including cancer and heart disease.28-32

By contrast PGE2 and PGI2 from Omega-6 PUFAs are pain-causing. Hence they are the targets of most over-the-counter pain killers. These prostaglandins and their precursor arachidonic acid are elevated during migraines and may sensitize of the trigeminal nerve which is the location of migraine pain.1, 15, 19, 20, 33, 34 In fact, the highest level of PGE2 receptors in the body are found in the trigeminal nucleus caudalis.22

Fortunately, when diets are high in omega-3 fatty acids such as EPA from fish oil, the good prostaglandins tend to supplant the bad.26

So, why then was it that studies of omega-3 supplementation have had mixed results for migraine?35-37

The potential answer gets at a key tenant of the Paleo Diet – just popping a few fish oil supplements and calling yourself healthy isn’t enough. It’s all about balance.

Due to the huge increase in vegetable oils and grain fed livestock in the western world, the ratio of omega-6 to omega-3 PUFAs in our diets have risen to 10:1 from an estimated 3:1 or even 2:1 in Paleolithic times.26, 38-40

To see if the ratio influenced migraines, a 2013 study by Ramsden et al, not only increased omega-3 in Migraineurs’ diets, but reduced the omega-6 content. The pain improved significantly. Interestingly, the investigators included a second group that only reduced omega-6 PUFAs in their diet. While not as dramatic, this group also improved.35

Issues with the high ratio of omega-6 to omega-3 fatty acids in the western diet go beyond migraines. The ratio has been associated with many chronic conditions including depression (due to its influence on serotonin), rheumatoid arthritis, inflammatory bowel disease, asthma, heart disease and chronic inflammation.26, 27, 38, 41

A Paleo Diet promotes a better omega-3 to omega-6 ratio. The best source of omega-3 PUFAs is EPA from fish, but other sources include walnuts, lean meats, and some vegetables such as broccoli and spinach.42 Just remember that the shift from omega-3s to omega-6 PUFAs in our bodies takes time – from 6 – 18 weeks.43

MAGNESIUM: THE PAINFULLY FORGOTTEN ELECTROLYTE

Magnesium is sometimes referred to as the “forgotten electrolyte” since it is frequently overshadowed by calcium in the research.44-46 Magnesium is involved in over 300 functions in our body, which means it is not a nutrient we want to forget about. Yet almost 48% of Americans eat less than the RDA.15, 44

Most magnesium is found in our bones and cells with less than 1% in our blood,45 which means that a blood test for magnesium isn’t very effective.47 Up to 14% of the population may be deficient and this deficiency has been associated with many chronic conditions including heart disease.48

Evidently, magnesium deficiency has been clearly linked to migraines.9, 47, 49, 50 In multiple studies, migraine sufferers had lowered levels of magnesium in their blood, saliva, and cerebrospinal fluid during attacks.51-56

Magnesium affects many processes linked to migraine including neurotransmitter release, serotonin receptors, inflammatory mediators, and the inhibition of platelet aggregation.56-63 It may even block some of the inflammatory effects of omega-6 PUFAs.44

Magnesium supplements help migraine sufferers.51, 56 Even more strikingly, people going to the emergency room with migraine pain are frequently treated with an infusion of magnesium sulfate which is more effective than the pharmaceutical treatments dexamethasone and metoclopramide.47, 57

Unsurprisingly with current migraine research pointing to electrolyte imbalances, the “forgotten electrolyte” may play a key role in migraine hyperexcitability.15

Sodium-potassium imbalance may trigger migraines, but overactive calcium channels could be the cause.2 High levels of calcium in the brain make neurons easily excitable.2, 44 Magnesium is a key regulator of calcium and might be able to control this calcium-induced hyperexcitability.44

In fact, in a review of migraine hyperexcitability, Welch proposed that the changes in magnesium levels during a migraine may be an attempt by the brain to restore electrolyte balance.2

Here again, migraines show why a properly balanced diet is far more important than just popping supplements.

With the concern over osteoporosis, daily calcium consumption has been increasing over the past four decades.44 This Western focus on calcium has led to one of the biggest criticisms of the Paleo Diet for its elimination of dairy. This is in spite of recent research questioning the benefits of high calcium intake and worse, linking it to heart disease.64-68

What may be more important than the absolute calcium level is the ratio of magnesium to calcium in the diet which has been decreasing.44 Not something to overlook considering increased magnesium consumption reduced all-cause mortality associated with high calcium intake.69

Worse yet, consuming too much calcium can exacerbate magnesium deficiency.70

The higher calcium-magnesium ratio of the Western diet may contribute to a variety of chronic conditions beyond migraine, including stress, metabolic syndrome, Type II Diabetes, hypertension and vascular disease.44

The Paleo Diet promotes a better calcium-magnesium ratio through the consumption of foods high in both including almonds, cashews, green leafy vegetables, and fish. While research is limited, it is believed that alcohol and sugary drinks can limit magnesium absorption.

ELIMINATING DIETARY PAIN

Food sensitivity remains one of the most common migraine triggers,71, 72 but the foods tend to be highly individual. A food diary is one way for migraine sufferers to identify their triggers. Though this can be difficult since foods interact and sometimes the migraine appears a day or more after eating the culprit foods.9

Fortunately, there may be another way to identify your triggers. Food that causes an IgG antibody response has been associated with migraines.9 Studies eliminating these foods have produced dramatic results with up to 93% of participants becoming headache free.71, 73, 74

Balancing Migraine Pain with a Paleo Diet | The Paleo DietWhile the point of an IgG-elimination diet is individualization, the table to the left shows the most common IgG-inducing food groups.71

This study found that an IgG-elimination diet also helped Irritable Bowel Disease, another condition affected by dietary imbalance.71, 75 Up to 50% of people with IBS suffer from migraines76 with neural hypersensitivity77 and mitochondrial DNA mutations75 linked to both.

We frequently recommend Paleo Dieters suffering from chronic conditions try an elimination diet. Seeing your allergist to help you identify IgG-provoking foods may be a shortcut to help you get past migraine pain.

Certainly PUFAs and magnesium have dominated the literature on diet and migraines – to the point that they were used as a proof of concept for literature research.78 But this doesn’t mean they are the only dietary factors. Both low fat79 and ketogenic diets80 improved migraine symptoms. Migraine hyperexcitability can be affected by the sodium-potassium balance in the diet and hydration status (with dehydration and hypohydration causing migraines).15

The underlying message is migraine pain may be a disease of imbalance. So, while I’ve reached for the Excedrin bottle more than a few times to get through my day, a balanced diet more attune with our evolutionary make-up may ultimately be what keeps us Migraineurs away from the medicine cabinet altogether.

Trevor Connor | The Paleo DietTrevor Connor is Dr. Cordain’s last mentored graduate student and will complete his M.S. in HES and Nutrition from the Colorado State University this year and later enter the Ph.D. program. Connor was the Principle Investigator in a large case study, approximately 100 subjects, in which he and Dr. Cordain examined autoimmune patients following The Paleo Diet or Paleo-like diets.

 

REFERENCES

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50. Innerarity, S., Hypomagnesemia in acute and chronic illness. Crit Care Nurs Q, 2000. 23(2): p. 1-19; quiz 87.

51. Peikert, A., C. Wilimzig, and R. Kohne-Volland, Prophylaxis of migraine with oral magnesium: results from a prospective, multi-center, placebo-controlled and double-blind randomized study. Cephalalgia, 1996. 16(4): p. 257-63.

52. Facchinetti, F., et al., Magnesium prophylaxis of menstrual migraine: effects on intracellular magnesium. Headache, 1991. 31(5): p. 298-301.

53. Schoenen, J., J. Sianard-Gainko, and M. Lenaerts, Blood magnesium levels in migraine. Cephalalgia, 1991. 11(2): p. 97-9.

54. Sarchielli, P., et al., Serum and salivary magnesium levels in migraine and tension-type headache. Results in a group of adult patients. Cephalalgia, 1992. 12(1): p. 21-7.

55. Ramadan, N.M., et al., Low brain magnesium in migraine. Headache, 1989. 29(9): p. 590-3.

56. Mauskop, A. and B.M. Altura, Role of magnesium in the pathogenesis and treatment of migraines. Clin Neurosci, 1998. 5(1): p. 24-7.

57. Shahrami, A., et al., Comparison of therapeutic effects of magnesium sulfate vs. dexamethasone/metoclopramide on alleviating acute migraine headache. J Emerg Med, 2015. 48(1): p. 69-76.

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60. McCarty, M.F., Magnesium taurate and fish oil for prevention of migraine. Med Hypotheses, 1996. 47(6): p. 461-6.

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62. Turlapaty, P.D. and B.M. Altura, Magnesium deficiency produces spasms of coronary arteries: relationship to etiology of sudden death ischemic heart disease. Science, 1980. 208(4440): p. 198-200.

63. Mody, I., J.D. Lambert, and U. Heinemann, Low extracellular magnesium induces epileptiform activity and spreading depression in rat hippocampal slices. J Neurophysiol, 1987. 57(3): p. 869-88.

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Vegetarian Diet | The Paleo Diet

Did you miss Vegetarian and Vegan Diets: Nutritional Disasters Part 1 or Part 2?
Read Part 1 HERE
Read Part 2 HERE

Vegetarian Diets: Other Nutritional Shortcomings

You don’t have to look any further than the ADA’s Position Statement28 or the USDA’s recommendations on vegetarian diets142 to discover additional nutrient shortcomings caused by plant based diets. The ADA matter of factly mentions that “…key nutrients for vegetarians include protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B12..28 The USDA notes that “…vegetarians may need to focus on…iron, calcium, zinc, and vitamin B12.142 These subtle admissions of potential nutrient deficiency problems associated with vegetarian diets represent the tip of a nutritional nightmare. Just as was the case with vegetarian diets and vitamin B12 deficiency, there is little credible scientific evidence to show that people eating a lifelong plant based diet (without taking supplements or eating fortified foods) can achieve adequate dietary intakes of omega 3 fatty acids (EPA and DHA), iron, zinc, iodine, calcium, and vitamin D. To this list you can also add vitamin B6 and taurine, an amino acid.

Mineral Deficiencies and Vegetarian Diets

One of the major complications with the assessment of dietary nutrient adequacy in vegetarian diets, or for that matter, any diet has to do with whether or not the vitamins and minerals measured in certain foods actually get absorbed into our bodies. The bioavailability of vitamins and minerals in foods is just as important in how they impact our health as is the simple content of these nutrients in a food. By now you know that phytate is not a good thing because it prevents absorption of essential minerals. Whole grains and legumes are rich sources of phytate. Accordingly, our bodies have great difficulty extracting certain minerals from these foods because they are tightly bound to phytate. Phytate in whole grains impairs calcium absorption and may adversely affect bone health. Further, phytate also binds zinc, thereby interfering with its assimilation and incorporation into our cells. To this list you can add iron and magnesium. Because vegetarian diets are virtually impossible to follow without including lots of whole grains, beans, soy and legumes, they are inherently high in phytate. This is why it is difficult or impossible for vegetarians and vegans to maintain adequate body stores of calcium, zinc and iron.

Zinc Deficiencies in Vegetarian Diets

From the discussion above, you know that zinc is crucial for normal male reproductive function, but it is also required for good health and disease resistance in virtually every cell in our bodies, whether you are a man, woman or child.20, 41 Marginal zinc status impairs our immune system, slows wound healing, adversely affects glucose and insulin metabolism, and damages our body’s built in antioxidant system.16, 55 Without adequate dietary zinc we experience more upper respiratory illnesses that last longer. Zinc lozenges can slow or prevent common cold symptoms, and zinc oxide creams applied topically can speed healing. If you have ever experienced painful cracked heels or nose bleeds that just wouldn’t stop, try rubbing zinc oxide ointments on these wounds – you will be amazed at how rapidly zinc can heal these stubborn sores. How we got into this problem (marginal zinc status or deficiencies) in the first place originates directly from our diets. Anybody eating excessive whole grains and/or legumes and not eating meat, fish or animal products on a regular basis45, 59, 62 puts themselves at risk for all illnesses and health problems associated with borderline or deficient zinc intakes.

Iron Deficiencies in Vegetarian Diets

Your body stores of iron run hand in hand with zinc. The same types of diets that produce zinc deficiencies also create iron deficiencies. High phytate vegetarian diets based upon whole grains, beans, soy and other legumes invariably cause iron deficiencies5, 135 which are the most common nutrient deficit worldwide. In the U.S. 9% of all women between 12 and 49 years are iron deficient, while 4% of 3 to 5 year old children have insufficient stores of this crucial mineral.25 If you are pregnant, low iron status increases your risk of dying during childbirth, and frequently causes low birth weights and preterm deliveries. Even more disturbing is the potential for iron deficiencies to prevent normal mental development in our children and young adults.39, 90, 96 As a parent, I would never wish upon my child or for that matter anyone else’s, a diet causing nutritional deficiencies known to impair brain development and normal mental function. But this is just the case if you eat a vegetarian diet and impose it upon your children. Plant based diets not only increase the risk of impaired cognitive function in your children, but will hamper your own mental functioning. Numerous experimental studies show that inadequate iron stores in adults can slow or impair tasks requiring concentration and mental clarity.73

One of the most important outcomes of diets that cause iron deficiencies is that they make us fatigued and tired. If you are an athlete or have a demanding job requiring physical exertion, low iron stores will invariably reduce your performance. A recent (2009) experiment involving 219 female soldiers during military training showed that iron supplements improved blood iron stores, increased performance for a 2 mile run and enhanced mood.92 Similarly a study by Dr. Hinton and colleagues demonstrated that iron supplements in iron deficient male and female athletes improved endurance performance and efficiency.56 Whether you are an athlete, a laborer or even an office worker, your best nutritional strategy to improve iron stores, add vigor to your life and improve performance is to eliminate whole grains and legumes from your diet by adopting The Paleo Diet.

The burden of proof that vegetarian diets will not produce multiple vitamin and mineral deficiencies lies upon the governmental (USDA) and dietary organizations (ADA) that recommend these diets to us all and tell us that they are safe.28, 142 You might expect that the experimental evidence surrounding vegetarian diet recommendations would be convincing and overpowering. Nothing could be further from the truth, particularly when it comes to iron deficiencies and vegetarian diets.

As always the devil is in the details when it comes to getting correct answers to nutritional questions. Scientists who believe that vegetarian diets don’t adversely affect our iron stores often cite scientific papers showing no difference between blood iron concentrations in vegetarians and meat eaters. What they don’t tell us is how iron measurements were performed in the experiments they quote to support their viewpoint. This information is absolutely essential in knowing if iron deficiencies exist or not. Any study examining blood levels of iron in vegetarians using either measurements of hemoglobin (an iron carrying substance in red blood cells) or hematocrit (the concentration of red blood cells) are unreliable indicators of long term iron status. A much better marker is an iron carrying molecule called ferritin.75 Virtually all epidemiological (population) studies of vegans or ovo/lacto vegetarians show them to be either deficient or borderline iron deficient when blood ferritin levels are measured. Given this nearly unanimous finding from epidemiological studies, you might think that either the USDA or the ADA would become concerned and re-examine their endorsement of vegetarian diets. Unfortunately, we still live with governmental and institutional dietary recommendations that may do considerable harm to our health.

The most convincing type of experiments to reveal whether or not vegetarian diets may cause our iron stores to nosedive are called dietary interventions. Why not put a large group of non-vegetarians on a plant based diet for an extended period and see what happens to their blood iron levels? Wow what a great idea – unfortunately no such study has ever been conducted. The closest we have come to this experiment is a short term study (8 weeks) by Dr. Janet Hunt and co-workers at the Grand Forks Human Nutrition Research Center in North Dakota.63 The results of this experiment were anything but conclusive as the researchers made a fundamental blunder in the design of their experiment – they forgot to include a control group. Without a control group, it is impossible to interpret the outcome of this or any experiment.

Nevertheless, when women were placed on lacto/ovo vegetarian diets, their intestinal iron absorption was reduced by 70%; however, inexplicably, blood ferritin levels (a marker of their long-term iron status) did not decline for the group as a whole. It should be noted that nearly half of the subjects did experience drops in blood ferritin concentrations. Because the authors of this study failed to include a control group, then extraneous variables likely swayed the experiment’s outcome. You recall from earlier in this essay that vegetarian diets caused 7 out of 9 women to stop ovulating. With the cessation of menstrual periods, monthly blood loses also cease which in turn prevents monthly iron losses because blood is a rich source of iron. Hence, in any study evaluating blood iron stores in women, it is absolutely essential to know if their normal menstrual cycles were altered. Unfortunately, Dr. Hunt did not provide us with this information, thereby making the correct interpretation of her experiment difficult or impossible.

In order to once and for all know whether or not vegetarian diets cause iron deficiencies, we would need to perform Dr. Hunt’s experiment again, for at least a year with more subjects, a control group and monitor changes in menstrual periods. You would think that this kind of very basic experimental evidence would have already been in place before any governmental or institutional organization told us that vegetarian diets were safe and didn’t cause nutritional deficiencies. Unfortunately, these precautionary steps have never been taken, and millions of Americans who adhere to vegetarian diets with the mistaken belief that they will benefit health-wise will actually suffer.

Iodine Deficiencies in Vegetarian Diets

A number of studies have reported that vegetarian and vegan diets increase the risk for iodine deficiency.40, 77, 102, 153 One study from Europe demonstrated that 80% of vegans and 25% of ovo/lacto vegetarians suffered from iodine deficiency.77 Additionally, a dietary intervention by Dr. Remer and colleagues in 1999 confirmed this epidemiological evidence.102 After only five days on ovo/lacto vegetarian diets, iodine status and function became impaired in healthy adults.102 The primary reason why vegetarian diets cause iodine deficiencies is that plant foods (except for seaweed) are generally poor sources of iodine compared to meat, eggs, poultry and fish. Gross deficiencies of iodine cause our thyroid glands to swell producing a condition known as goiter, and in pregnant women result in severe birth defects called cretinism.141 Because salt is fortified with iodine, most people in the U.S. and Europe rarely develop gross iodine deficiencies.40, 140, 141 However moderate to mild iodine deficiencies appear in westernized countries, particularly among vegetarians and vegans.77, 102 Moderate iodine deficiency impairs normal growth in children and adversely affects mental development.140, 141, 152 A large meta analysis revealed that moderate childhood iodine deficiency lowered I.Q. by 12-13.5 points.153 Paleo Diets are not just good medicine for adults, but they also ensure normal physical and mental development in our children because of their high iodine content.

One of the problems with plant based diets is that they may put into play a vicious cycle that makes iodine deficiencies worse. When the thyroid glands iodine stores become depleted, as often happens with vegetarian diets, then certain antinutrients found in plant foods can gain a foot hold and further aggravate iodine shortages. Soy beans and soy products are frequently a mainstay in vegetarian diets and may promote inflammation.66 Unfortunately soy contains certain antinutrients (isoflavones) that impair iodine metabolism in the thyroid gland,43, 95 but only when our body stores of iodine are already depleted. Other plant foods (millet, cassava root, lima beans, sweet potatoes, and cruciferous vegetables [broccoli, cauliflower, turnips, kale, cabbage]) also contain a variety of antinutrients which hinder normal iodine metabolism. So, plant based diets put us at risk for developing iodine deficiencies in the first place, and when this happens our bodies become vulnerable to plant antinutrients that worsen the pre-existing deficiency. The important point here is that antinutritional compounds have virtually zero effect upon our thyroid gland when our body stores of iodine are normal and fully replete. Because meats, fish, eggs and poultry are rich sources of iodine, you will never have to worry about this nutrient when you eat Paleo style.

Vitamin D and Vitamin B6 Deficiencies in Vegetarian Diets

In my paper, Cereal Grains: Humanity’s Double Edged Sword, I have pointed out how excessive consumption of whole grains adversely affects vitamin D status in our bodies.148 Hence it goes without saying that vitamin D deficiencies run rampant in vegetarians worldwide because it is nearly impossible to become a full-fledged vegetarian without eating lots of grains. In the largest study of vegetarians ever undertaken (The Epic-Oxford Study), Dr. Crowe and fellow researchers reported that blood concentrations of vitamin D were highest in meat eaters and lowest in vegans and vegetarians.29 Nearly 8% of the vegans maintained clinical deficiencies of vitamin D. Vitamin D is not really a vitamin at all, but rather a crucial hormone that impacts virtually every cell in our bodies.

By now, you are starting to get a pretty good picture of what a nutritional nightmare vegetarian diets really are. When we let the data speak for itself, the number of nutrient deficiencies and adverse health effects associated with plant based diets are appalling and far outweigh any supposed health effects of this unnatural way of eating. One of the biggest kept secrets about vegan or vegetarian diets is that they frequently cause vitamin B6 deficiencies. If you recall, neither the ADA,28 nor the USDA142 has given us any warning that meatless diets increase our risk for vitamin B6 deficiencies.

On paper, it would appear that vegetarian diets generally meet daily recommended intakes for vitamin B6. This assumption comes primarily from population surveys examining the foods that vegans and vegetarians normally eat. In contrast, when blood samples are analyzed from people relying upon plant based diets, they unexpectedly reveal that long term vegetarians and vegans frequently are deficient vitamin B6. A recent study of 93 German vegans by Dr. Waldman and colleagues showed that 58% of these men and women suffered from vitamin B6 deficiencies despite seemingly adequate intakes of this essential nutrient.131 It turns out that the type of vitamin B-6 (pyridoxine glucoside) found in plant foods is poorly absorbed.47, 103 The presence of pyridoxine glucoside in plant foods along with fiber has been reported to reduce the bioavailability of vitamin B6 so that only 20 to 25% is absorbed and completely utilized.47 In contrast, vitamin B6 found in animal foods is easily assimilated, and an estimated 75 to 100% fully makes its way into our bloodstreams.47

Compelling evidence that vegetarian diets relying upon the plant form of vitamin B6 adversely affect our body’s overall vitamin B6 stores comes from Dr. Leklem’s laboratory at Oregon State University.47 Nine women were put on diets either high or low in the plant form of vitamin B6 (pyridoxine glucoside). After only 18 days, the high pyridoxine glucoside diets consistently lowered blood concentrations and other indices of vitamin B6 status. Deficiencies in this vitamin elevate blood homocysteine concentrations and increase our risk for cardiovascular disease similar to shortages of folate and vitamin B12. Further, vitamin B6 is an important factor in normal immune system functioning149 and shortfalls of this crucial nutrient have been identified in depression150 and colorectal cancer.151

Omega 3 Fatty Acid Deficiencies in Vegetarian Diets

A few years ago I was involved in a series of experiments here at Colorado State University in which we were interested in determining how high and low salt diets affected exercise-induced asthma. Our working hypothesis was that high salt diets would make measures of lung function worse, and low salt diets would improve things. One of our concerns with this experiment was to somehow make sure our subjects had fully complied with either the high or low salt diets. Completely removing salt from your diet is not an easy thing to do, and if some of our subjects had decided to sneak in a piece of pizza or some Doritos, it would mess up the experiment’s outcome. Fortunately, there was an easy way to figure out if our subjects had been compliant with the prescribed diets. All we had to do was to spot check their urine, because measurement of urinary salt levels is an accurate gauge of dietary salt consumption. High urinary salt levels universally reflect high salt consumption, whereas low urinary salt concentrations indicate low salt consumption. Short of major disease, there is virtually no other way high amounts of salt in the urine don’t indicate high amounts of salt in the diet.

In a similar manner, there are equivalent telltale indicators of omega 3 fatty acids in our bloodstreams that tell us beyond a shadow of a doubt whether or not we have regularly consumed fish, seafood or other good sources these healthful fats. The three main types of omega 3 fatty acids we need to concern ourselves with are EPA, DHA and ALA. EPA and DHA are called long chain omega 3 fatty acids and are only found in high amounts in fish, seafood, certain meats, and other foods of animal origin. Plant foods contain no EPA or DHA. On the other hand, ALA is called a short chain fatty acid and is found in both plant and animal foods. Both EPA and DHA in our red blood cells are markers of these important fatty acids in our diet. Without good dietary sources of EPA and DHA such as are found in fish, seafood and certain meats, our blood levels of EPA and DHA will decline. Just like salt in our urine was an indicator for dietary salt, EPA and DHA concentrations in our red blood cells are markers for our dietary intake of these long chain omega 3 fatty acids. It is virtually impossible to achieve high blood levels of EPA and DHA without regularly consuming fish, seafood and certain meats and organ meats (particularly grass produced meats and organ meats).

One of the major nutritional shortcomings in vegans is that they obtain absolutely no EPA or DHA from their diets.108, 110, 111 Consequently, they are totally dependent upon plant based ALA, supplements or fortified foods to obtain these healthful long chain omega 3 fatty acids. Without supplements or fortified foods, all vegans will become deficient in EPA and DHA because plant based ALA is inefficiently converted into these long chain fatty acids in our bodies. The liver converts less than 5% of ALA into EPA and less than 1% of ALA into DHA.15, 97 Virtually every epidemiological study that has ever been published shows that vegans, who do not supplement or consume long chain omega 3 fortified foods, to be deficient in both EPA and DHA76, 88, 108, 110, 111 Lacto/ovo vegetarians don’t fare much better because milk and egg based vegetarian diets simply do not supply sufficient DHA or EPA to maintain normal blood concentrations.88, 111

There is little doubt that vegan or vegetarian diets cause reductions in blood concentrations of DHA and EPA, which in turn represent a potent risk factor for many chronic diseases. Perhaps the single most important dietary recommendation to improve your health and prevent illness is to increase your dietary intake of EPA and DHA. Thousands of scientific papers covering an assortment of diseases clearly show the health benefits of these fatty acids. In randomized clinical trials in patients with pre-existing heart disease, omega-3 fatty acid supplements significantly reduced cardiovascular events (deaths, non-fatal heart attacks, and non-fatal strokes).19, 48, 138 Omega-3 fatty acids lessen the risk for heart disease through a number of means including a reduction in heart beat irregularities called arrhythmias, a decrease in blood clots, and reduced inflammation which is now known to be an chief factor causing atherosclerosis or artery clogging.

In addition to lowering the risk for heart disease, regular consumption of fish or supplemental omega-3 fatty acids may be useful in averting, treating, or improving a wide range of diseases and disorders, including virtually all inflammatory diseases (any disease ending with “itis”): rheumatoid arthritis,99 inflammatory bowel disorders (Crohn’s disease, ulcerative colitis), periodontal disease (gingivitis). Also mental disorders (autism, depression),3, 84 postpartum depression, bi-polar disorder, borderline personality disorder, impaired cognitive development in infants and children) may respond favorably to these beneficial fatty acids. Further, acne, asthma, exercise induced asthma, many types of cancers,120 macular degeneration, pre-term birth, psoriasis, insulin resistance, type 2 diabetes, cancer cachexia, intermittent claudication, skin damage from sunlight, IgA nephropathy, lupus erythematosus, type 1 diabetes, multiple sclerosis, and migraine headaches also improve with omega 3 fatty acids.

Taurine deficiencies in Vegetarian Diets

Although the number of nutrients which are frequently lacking in vegetarian and vegan diets may seem endless to you, we are now at the end of the list. Taurine is an amino acid (actually a sulfonic acid because it lacks a carboxyl group) in our bloodstreams that has multiple functions in every cell of our body. Unfortunately, this nutrient is not present in any plant food and is found in low concentrations in milk (6 mg per cup).80 In contrast, all flesh foods are excellent sources of taurine.80 For example, ¼ pound of dark meat from chicken provides 200mg of taurine. Shellfish are even richer still with over 800mg per quarter pound. The daily taurine intake in non-vegetarians is about 150mg, whereas lacto/ovo vegetarians take in about 17mg per day, and vegans get none. Although our livers can manufacture taurine from precursor molecules, our capacity to do so is limited – so much so that this amino acid is regularly fortified in infant formulas. As you might expect, studies of vegans show that their blood taurine levels are lower than meat eaters.81, 100 How depleted blood concentrations of taurine affect our overall health, is not entirely understood. Nevertheless, shortages of this amino acid and omega 3 fatty acids (EPA and DHA) may cause certain elements (platelets) in our blood to clot more rapidly which in turn increase our risk for cardiovascular disease.85, 91 Despite their meat free diets, vegetarians almost always exhibit abnormal platelets that excessively adhere to one another. In one dietary intervention, Dr. Mezzano and colleagues demonstrated that after eight weeks of EPA and DHA supplementation normal platelet function was restored in a group of 18 lacto/ovo vegetarians.85 Obviously, compromised taurine status will never become a problem in Paleo Diets, because meat, fish, poultry and animal products are consumed at nearly every meal.

In summary, if you have adopted, or are considering adopting a plant based diet for reasons of improving your health, make sure you reread this chapter and look up all of the references I have provided you. The evidence that vegetarian and vegan diets almost always cause a multitude of nutritional deficiencies is overwhelming and conclusive. Over the course of a lifetime, vegetarian diets will not reduce your risk of chronic disease and will not allow you to live longer. Rather, this abnormal way of eating will predispose you to a host of health problems and illnesses. Vegetarianism is an unnatural way of eating that has no evolutionary precedence in our species. No hunter-gatherer society ever consumed a meatless diet, nor should you. The ADA has labeled The Paleo Diet a fad diet because it eliminates “two entire food groups” (grains and dairy). Yet hypocritically, they exempt vegan diets from this characterization despite also eliminating two food groups (dairy, meats and fish). If The Paleo Diet is a fad diet, then it is the world’s oldest.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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Vegetarian Diet | The Paleo Diet

Did you miss Vegetarian and Vegan Diets: Nutritional Disasters Part 1? Read it HERE

Vegetarian Diets and Homocysteine

Vitamin B12 deficiencies caused by vegetarian or vegan diets are just as devastating to adults as they are to infants and pregnant women. Vitamins technically are defined as “organic catalysts” – meaning that without their presence in our diets, our metabolic machinery slows, or is sufficiently damaged to eventually cause illness and disease. One of the most destructive changes in our bodies caused by vitamin B12 deficiency is the appearance of a toxic substance in our bloodstream known as homocysteine. Without sufficient dietary sources of vitamin B12, a chemical reaction within our bodies is impaired and causes blood concentrations of homocysteine to rise. Homocysteine is a toxin for almost every cell in our bodies, and increases the risk for birth defects, infertility, dementia, psychological illness, stroke, heart attacks, blood vessel disease, blood clots, osteoporosis and overall death rates. Worldwide studies of vegetarians and vegans show that the less animal food they eat, the higher are their blood concentrations of homocysteine.9, 21, 38, 60, 67, 70, 94, 101 Let’s take a look at how vegetarian diets raise blood concentrations of homocysteine and increase the risk for numerous diseases.

Homocysteine and Cardiovascular Disease

It is widely assumed that vegetarian diets reduce the risk for cardiovascular disease and heart attacks because they lower total and saturated fats in our diets. Unfortunately, this simplistic explanation is only part of the story. Total fat and saturated fat have been shown in large meta analyses to have negligible effect upon the atherosclerotic process that clogs the arteries and causes heart and blood vessel disease.143-146 In contrast, meta analyses published in the past 15 years have confirmed that homocysteine is an independent risk factor for cardiovascular disease and heart attacks.61, 130 The higher your blood levels of homocysteine, the greater will be your risk of having a stroke or heart attack. As I mentioned earlier, homocysteine is toxic to almost all cells in our bodies. It is particularly dangerous when high concentrations build up in our bloodstreams because it damages the cells lining blood vessels. This initial injury to the blood vessels represents one of the first steps in the artery clogging process. If blood concentrations of homocysteine remain high and the blood vessel damage goes on unabated for decades, it may result in fatal strokes and heart attacks. A recent (2008) meta analysis by Dr. Humphrey and colleagues indicated that for each (5 micromol/L) increase in blood homocysteine levels, the risk for cardiovascular disease events increased by approximately 20%.61

Because vegetarian diets cause vitamin B12 levels in the bloodstream to plummet, which in turn causes homocysteine levels to dangerously rise, you might expect to find high rates of cardiovascular disease in strict lifelong vegetarians. One of the problems in examining cardiovascular disease in vegetarians from the U.S. and Europe is that many of them aren’t strict vegetarians, and typically haven’t consumed vegetarian diets for their entire lives. All of these variables tend to confound the results of epidemiological studies. Given this scenario, what better place to examine vegetarian diets and cardiovascular disease than in India? With a population of 1.17 billion people, 31 % (362,700,000) of whom are vegetarians,42 India represents a country which can give us insight into study cardiovascular disease and plant based diets. As opposed to vegetarians in the U.S. and Europe, many Indian vegetarians are committed to lifelong vegetarian diets due to their religious convictions and family conventions.

If vegetarian diets provide protection from cardiovascular disease as the ADA suggests, then you might expect to find a low prevalence of heart disease and stroke in India because almost one third of its population are vegetarians. Unfortunately, this is not the case.137 In reality, the incidence of cardiovascular disease is much higher in India than in most other places in the world. Moreover, Indians develop cardiovascular disease at a much earlier age than people from other countries. In the largest study ever of 368 lifelong Indian vegetarians with cardiovascular disease, Dr. Kumar and co-workers showed that heart disease was higher in vegetarians and that they had lower blood levels of vitamin B12.79 I quote Dr. Kumar, “We believe that the beneficial effect of a vegetarian diet in this population is circumvented by deficiency of vitamin B12.

Homocysteine and Neurological Diseases

Not only is homocysteine toxic to our blood vessels, but numerous studies also have found that it adversely affects brain function, behavior and mood.23, 129 People with higher blood concentrations of homocysteine have a greater risk for Alzheimer’s disease, dementia, depression, Parkinson’s disease and stroke. In a comprehensive 2010 review of 1,627 articles on high blood levels of homocysteine and vitamin B12 Dr. Werder133 concluded that: “Hyperhomocysteinemia (high blood levels of homocysteine) with or without hypovitaminosis B12 (low blood levels of vitamin B12) is a risk factor for dementia.” In addition to vitamin B12 deficiencies another B vitamin, folate, can cause blood concentrations of homocysteine to rise. However in a study involving 2,403 older people, Dr. Clarke and colleagues24 found that, “the relative importance of vitamin B12 deficiency as a determinant of homocysteine concentrations and cognitive impairment is probably greater than that of folate deficiency in older adults.” Additionally, a recent study by Dr. Selhub’s research group showed that high dietary intakes of folate seems to make B12 deficiencies worse by further increasing blood concentrations of homocysteine.114 This is precisely the dietary pattern found in the blood of most vegetarians – low B12 and adequate or elevated folate. Is it any wonder why so many vegetarians and vegans have dangerously high blood levels of homocysteine?

Homocysteine and Bone Disease

The list of chronic diseases associated with high blood concentrations of homocysteine seems almost endless and has recently been extended to bone disease. By raising blood homocysteine levels, vegetarian diets may not only increase your risk for neurological disorders and cardiovascular disease, but they also increase bone fracture risk. The notion that vegetarians have weaker bones than their meat eating counterparts was verified in the largest study ever undertaken in a vegetarian population (9,420 vegetarians and 1,126 vegans). The authors of the EPIC-Oxford study concluded that, “The higher fracture risk in the vegans appeared to be a consequence of their considerably lower mean calcium intake.2 Low calcium and vitamin D intakes are well known risk factors for bone fractures and osteoporosis, and these nutritional deficiencies are common in vegan and vegetarian populations. But to add insult to injury, you can now add another strike against vegan and vegetarian diets in promoting bone disease. Since 2003, numerous studies have identified low B12, low folate or high homocysteine blood levels as risk factors for poor bone density, increased fractures, or osteoporosis.2, 4, 17, 34, 51, 53, 54, 58, 78, 82, 112, 125

Although we don’t completely understand how high blood levels of homocysteine adversely affect bone, tissue studies have identified a number of mechanisms. First homocysteine seems to impair the normal bone mineralization process.17 It also causes an accelerated breakdown of bone and inhibits the formation of new bone cells.51 Some of the best evidence implicating homocysteine in bone disease comes from human dietary interventions. In a two year study of 559 elderly women in Japan, Dr. Sato and fellow researchers showed that supplementation of vitamin B12 and folate reduced blood concentrations of homocysteine by 38%.112 But more importantly women in the vitamin supplemented group suffered 33 fewer hip fractures than women in the un-supplemented control group.

One of the best ways you can prevent hip fractures is to follow The Paleo Diet. Because you will be eating meat and fish at virtually every meal, you won’t have to worry about vitamin B12 deficiencies, as these two foods are our best sources of this essential vitamin. The other mainstay of The Paleo Diet is fresh fruit and veggies which are rich sources of the B vitamin, folate. The combination of lots of meat and fish along with plenty of fruits and vegetables at every meal will ensure that you do not develop vitamin B12 or folate deficiencies and that your blood homocysteine levels will remain low throughout your life – just as nature intended.

Homocysteine and Infertility

Before I leave homocysteine, I’ve got to cover one more topic that for some of you may be the most important revelation of all about this noxious molecule. By now, you know that elevated blood concentrations of homocysteine result primarily from too little vitamin B12 and folate in our diets. When adequate stores of these two 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. I’ve previously outlined how 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 and folate can severely reduce your chances for successful fertilization and conception. Infertility is a huge problem in both the U.S. and elsewhere11, 122 and affects at least 6 million people in the U.S. or more importantly about 7.4% of the reproductive age population.119 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 and/or folate are low and your homocysteine is elevated, your chances for a normal conception and pregnancy will be significantly reduced.8, 12-14, 30, 36, 93, 98, 116, 128

The injurious effects of homocysteine in our bones and in our cardiovascular and nervous systems have been much better studied than in our reproductive systems. Nevertheless, it is becoming increasingly evident that the low vitamin B12 and folate status responsible for elevated homocysteine is toxic to both sperm and egg cells and may represent a major, previously unrecognized 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.65 Additionally, a number of these earlier studies hinted that vitamin B12 supplementation could improve sperm function and vigor and even boost male fertility.57, 65

If we fast forward to the 21st century, in the past five to ten 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 homocysteine68 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.13, 126

Vegetarian Diets: Additional Fertility Problems

Menstrual Problems caused by Vegetarian Diets

In addition to B vitamin deficiencies and elevated blood concentrations of homocysteine, vegetarian 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. Not all types of scientific experiments have equal clout in establishing cause and effect. Of the five studies, four were epidemiological (population) studies and one was an actual experimental intervention. Because dietary interventions represent the most powerful experimental procedure for determining if dietary changes improve health or cause illness, they carry more weight than epidemiological studies. Let’s take a look at the only dietary intervention 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.147 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 takeaway: 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.31 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 deficiencies32, 44, 45, 62 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%.44 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.117 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.20, 32, 44, 45, 62 Numerous studies have shown that infertile/subfertile men had poor seminal quality that was associated with vegetarian diets6, 65 or 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.136 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.37 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.123

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 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.

In Vegetarian and Vegan Diets: Nutritional Disasters Part 3 we’ll discuss the additional copious shortcomings of vegetarian and vegan diets and why The Paleo Diet is optimal for health and wellbeing.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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119. Stephen EH, Chandra A. Declining estimates of infertility in the United States: 1982-2002. Fertil Steril. 2006 Sep;86(3):516-23.

120. Szymanski KM, Wheeler DC, Mucci LA. Fish consumption and prostate cancer risk: a review and meta-analysis. Am J Clin Nutr. 2010 Nov;92(5):1223-33.

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Is human fecundity declining in Western countries? Hum Reprod. 2010 Jun;25(6):1348-53.

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Calcium Leafy Vegetables | The Paleo Diet

More and more high-profile individuals are achieving measurable results on The Paleo Diet. These public triumphs threaten the antiquated low fat, high carbohydrate diets still officially endorsed by the government and prominent medical institutions. Accordingly, defenders of the low-fat doctrine are increasingly lashing out against the Paleo movement.

Just last month, The Wall Street Journal publicized NBA superstar Lebron James’ Paleo success, encapsulated by a viral photo posted to his Instagram account.1 This prompted NBC’s The Today Show to publish an article by Registered Dietitian Elisa Zied, in which Zied asserts, “There’s little science supporting the weight loss or health benefits of a Paleo diet.”2

According to Zied, the Paleo Diet “falls short on calcium and vitamin D,” and includes proportionally too much protein and fat and not enough carbohydrates. Paleo detractors say surprising things, but Zied’s comments are particularly fantastic. Let’s start with her vitamin D claim.

Vitamin D

Many are of the opinion the Paleo Diet is vitamin D deficient with the exclusion of milk, which is typically fortified with vitamin D. This would imply that non-Paleo Diets are vitamin D adequate only due to supplementation. After all, fortified milk is simply a food combined with a supplement. It would therefore be strange to call the Paleo diet vitamin D deficient when vitamin D supplements, if necessary, could always be added to the Paleo Diet.

According to the Institute of Medicine (IOM), we should be consuming 600 IU/day of vitamin D with an upper limit of 4,000 IU/day.3 Excluding fortified foods, the foods richest in vitamin D are fish and seafood, which, of course, are Paleo compliant. Just 100g of herring, for example has over 1,600 IU. Mackerel, sardines, salmon, trout, halibut, and shrimp are also particularly good sources.

Calcium

Others speculate the Paleo Diet also “fall short on calcium” because it excludes dairy. The IOM recommends 1,000 mg/day of calcium for adults with an upper limit of 2,500 mg. The foods highest in calcium are Paleo foods, including leafy green vegetables, herbs, and clams. A standard Paleo Diet, including plenty of leafy greens and seafood provides plenty of calcium.

Fat to Protein Ratio

In her article, Zied references a recent review of 19 studies published in PLoS, which concluded that overweight and obese people lose similar amounts of weight whether on low-carb or low-fat diets.4 But if you look at those 19 studies, one by one, the low-carb, Paleo Diets are clearly favorable. 9 of the 19 studies showed cardiovascular disease risk factors decreased on low-carb diets compared to low-fat diets. 8 of the studies suggest that low-carb and low-fat diets yield similar results, and only 2 studies, both published by the same author, suggest low-fat diets are better. Furthermore, the PLoS study did not include at least 10 additional randomized controlled trials (RCTs) comparing low-carb and low-fat diets, all of which show low-carb diets to be superior for weight loss and/or the prevention of metabolic syndrome and cardiovascular disease.5, 6, 7, 8, 9, 10, 11, 12, 13, 14

The latest, recently published study, funded by the National Institutes of Health concluded, “The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet. Restricting carbohydrate may be an option for persons seeking to lose weight and reduce cardiovascular risk factors.”15 Zied claims little scientific evidence supports the Paleo Diet, but in fact over 60 published studies support core aspects of the diet.

Criticisms to the Paleo Diet are consistently unscientific, which suggests these challenges are perhaps motivated by an interest in protecting the obsolete low-fat model of nutrition.

Christopher James Clark, B.B.A.
@nutrigrail
Nutritional Grail
www.ChristopherJamesClark.com

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.

References

1. Cohen, Ben. (August 18, 2014). Why LeBron James Is Suddenly Skinny. The Wall Street Journal. Retrieved September 11, 2014

2. Zied, Elisa. (August 21, 2014). Want to try LeBron James’ Paleo diet? 3 things we get wrong about carbs. Today.com. Retrieved September 11, 2014.

3. Committee to Review Dietary Reference Intakes for Vitamin D and Calcium. (November 2010). Dietary Reference Intakes for Calcium and Vitamin D. Institute of Medicine. Retrieved September 11, 2014.

4. Cameron, W. (July 2014). Low Carbohydrate versus Isoenergetic Balanced Diets for Reducing Weight and Cardiovascular Risk: A Systematic Review and Meta-Analysis. PloS One, 9(7). Retrieved September 11, 2014.

5. Guldbrand, H., et al. (August 2012). In type 2 diabetes, randomisation to advice to follow a low-carbohydrate diet transiently improves glycaemic control compared with advice to follow a low-fat diet producing a similar weight loss. Diabetologia, 55(8). Retrieved September 11, 2014.

6. Volek, J., et al. (April 2009). Carbohydrate Restriction has a More Favorable Impact on the Metabolic Syndrome than a Low Fat Diet. Lipids, 44(4). Retrieved September 11, 2014.

7. Shai, I., et al. (July 2008). Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet. New England Journal of Medicine, 359(3). Retrieved September 11, 2014.

8. Gardener, C., et al. (March 2007). Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal WomenThe A TO Z Weight Loss Study: A Randomized Trial. Journal of the American Medical Association, 297(9). Retrieved September 11, 2014.

9. Daly, ME., et al. (January 2006). Short-term effects of severe dietary carbohydrate-restriction advice in Type 2 diabetes—a randomized controlled trial. Diabetic Medicine, 23(1). Retrieved September 11, 2014.

10. Volek, J., et al. (2004). Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition Metabolism, 1(13). Retrieved September 11, 2014.

11. Yancy, W. et al. (May 2004). A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia: A Randomized, Controlled Trial. Annals of Internal Medicine, 140(10). Retrieved September 11, 2014.

12. Brehm, B., et al. (July 2013). A Randomized Trial Comparing a Very Low Carbohydrate Diet and a Calorie-Restricted Low Fat Diet on Body Weight and Cardiovascular Risk Factors in Healthy Women. Journal of Clinical Endocrinology & Metabolism, 88(4). Retrieved September 11, 2014.

13. Sondike, S., et al. (March 2003). Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. Journal of Pediatrics, 142(3). Retrieved September 11, 2014.

14. Bazzano, et al. (September 2, 2014). Effects of Low-Carbohydrate and Low-Fat Diets: A Randomized Trial. Annals of Internal Medicine, 161(5). Retrieved September 11, 2014.

15. Ibid, Bazzano.

Easy Baked Kale Chips | The Paleo Diet

Kale is often touted to be one of the healthiest vegetables on the planet. It belongs to the Brassica family which includes cabbage, collard greens, and broccoli. Kale’s nutrient profile is outstanding when it comes to the antioxidant Vitamins A, C, and K. In fact, 1 cup of kale will supply your body with the 1180.1% of the %DV requirement for Vitamin K. It also has many sulfur-containing phytonutrients. When compared to all other vegetables Kale ranks superior in antioxidant concentrations.

If you’re following Paleo, consider incorporating this nutritious vegetable in your diet. Where to start with this leafy green? Give our baked kale chips a try – an easy baked, delicious snack to keep your hunger at bay.

Ingredients

Serves 3-4

  • 3-4 large leaves of kale (preferably organic)
  • 1 Tbsp Coconut or olive oil
  • Favorite Paleo spice medley

Directions

1. Preheat oven to 350° F.

2. Rinse kale leaves and shred each leaf into chip-sized pieces, discarding the center stem.

3. In a Tupperware container, add coconut or olive oil and Paleo spices. I personally prefer sage, basil, red pepper flakes, black pepper, and oregano or thyme.

4. Seal container and toss ingredients until all leaves are fully coated.

5. Spread seasoned kale leaves on a non-stick cooking sheet. Make sure that each leaf is completely opened and not crumpled to ensure even cooking.

6. Place the kale chips in the oven and bake for 12 minutes or until crisp around the edges.

7. Remove the kale chips from your oven and place them in a bowl or plate to cool.

8. Enjoy!

 
Best,

Kyle Cordain, The Paleo Diet Team

Fibromyalgia, Pregnancy, Calcium | The Paleo Diet

Hello Dr. Cordain,

I was wondering if you would tell me if I can start The Paleo Diet while pregnant? I’m coming up to 17 weeks and suffer from Fibromyalgia. My doctor recommended this diet regiment. He advised I cut out pulses, which I eat a lot of, and wheat, which I don’t often eat much of, and to cut dairy products. But, I thought calcium intake was very important during pregnancy? I also use soy milk in cereals and the soy shakes. I was told to stop consuming all of these foods for a month or so to see how I feel. My stomach feels less bloated and I feel better, but feel I may need longer than a month on this diet to relieve aches and pains induced by my condition. I know some people suffer terribly from Fibromyalgia everyday, but my symptoms come and go. I look forward to hearing from you.

Marina

Dr. Cordain’s Response:

Marina,

The Paleo Diet excludes all grains, dairy, legumes, soy, sugar, unbalanced oils, and processed foods. The Paleo Diet emphasizes eating nutrient dense anti-inflammatory food that is derived from the earth in an unprocessed state. These foods include sustainably raised meat, fruit, vegetables, seeds, nuts, and healthy oils like coconut and olive.

Fibromyalgia is characterized by chronic and sometimes severe pain throughout the entire human body. Its exact cause has yet to be determined, but many people have had success healing their Fibromyalgia with The Paleo Diet.

I would strongly advise you to cut out wheat, dairy, and soy to treat your condition and to reduce overall inflammation in your body. Many people believe that soy milk is a healthy alternative to dairy-based milk for meeting the human calcium requirement. In reality, soy milk has many harmful properties that can actually inhibit absorption of calcium and other vital minerals and nutrients. Increasing you intake of fish is not only a good source of calcium, but it is also very rich in Omega-3 which is essential to development.

Many individuals who adopt The Paleo Diet question whether their calcium intake is sufficient, especially during pregnancy if dairy products are not permitted.

Foods that Naturally Contain High Levels of Calcium and Magnesium

Fish
  • Sardines
  • Salmon
  • Other small fish with soft cooked bones
Leafy Greens
  • Spinach
  • Kale
  • Lettuce chard
  • Arugula
Bone Broth
Dried Fruit
  • Apricots
  • Figs

All of the options above should provide your body with an adequate amount of calcium. It’s also worth mentioning that Vitamin D is an absolutely necessary component for synthesizing calcium and magnesium. Modern society emphasizes a lifestyle that is based on “indoor” activities. You can take all the calcium your heart desires, but if you are deficient in Vitamin D your calcium levels can still remain deficient!

The number one source of Vitamin D is sunlight. Spending only twenty minutes a day in full sunlight can provide your body with the necessary levels of vitamin D required for synthesizing calcium. If you live at a latitude that receives little sunlight, or if you lead a busy lifestyle that prevents you from getting outdoors, than you should take a Vitamin D supplement. A dosage of 2000 IU of Vitamin D per day is adequate for most adults. If you still feel that you are unable to meet your calcium requirements, you may want to consider taking a calcium supplement or drinking pure water that has been fortified with calcium.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

Affiliates and Credentials