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Dangers of Avoiding Meat

A vegetarian diet focuses on plants for food. These include fruits, vegetables, dried beans and peas, grains, seeds and nuts. There is no single type of vegetarian diet. People who follow vegetarian diets can get all the nutrients they need. However, they must be careful to eat a wide variety of foods to meet their nutritional needs. Nutrients vegetarians may need to focus on include protein, iron, calcium, zinc and vitamin B12.

The most common approaches are these:

  • Semi-vegetarian. You still eat animal products, but more selectively. Many semi-vegetarians eat chicken and fish but not red meat.
  • Pescatarian. You avoid meat and poultry but still eat fish and seafood.
  • Lacto-ovo vegetarian. You skip all meat, fish, and poultry but include dairy and eggs in your diet.
  • Vegan. This solely plant-based diet is the strictest form of vegetarianism. You eat no animal products at all—not even eggs or dairy products.

Watch your nutrition

Vegetarian and vegan diets can be healthy, but they can lack certain nutrients. You may have to use a little creativity to ensure you get enough protein, calcium, iron, and vitamin B12.

You can find many of these nutrients in eggs and dairy if you’re vegetarian, and from plant sources if you’re vegan. But you may need an added boost. Because vitamin B12 is found only in animal sources, if you’re a vegan you might consider taking a supplement. Omega-3 fatty acids are found in both fish and flaxseeds, but your body doesn’t absorb the plant-based form as readily as the omega-3s from seafood. Plant-based supplements are available if your diet needs more of these heart-healthy fats.

Meat vs veggie: From depression to infertility, how your choice of diet can wreak havoc on your health –

People who adopt vegan diets for health reasons never seem to be satisfied with just being vegan. They’re inclined to pile on more restrictions like no added oils or no cooked foods, or only whole plant foods, or even no nuts and seeds. If any of those restrictions had actual benefits, it would be one thing of course. But they don’t, and they can actually work against good health for vegans.

Researchers with the WHO are also taking a new look at protein needs—and some believe that these needs may be higher than previously believed. That’s not a big deal for the average omnivore, and probably not for the average vegan, either. But for those vegans who eat a raw foods diet or a super-low-fat diet that minimizes higher-protein foods, it could be.

The health argument is not foolproof. If people don’t get the intended benefit—reduced cholesterol or weight loss—they don’t have much reason to stick with a vegan diet. In contrast, the ethical argument for veganism always delivers on its promise. It is always the most compassionate choice and it always promotes an ethic of justice for animals.

The health argument isn’t unique. People who are focused only on the health aspects of a vegan diet are more likely to be enticed by other dietary philosophies that make promises about improved health. For ethical vegans, there is no comparable or alternative way of eating and living.

There is, of course, a pretty good argument for eating more plants (lots more plants) and less animal food, but no one has shown that you must eat a 100 percent plant diet in order to be healthy. So to make an argument for a 100% vegan diet based on health benefits alone, we have no choice but to stretch the truth. We have to overstate the benefits of vegan diets, and sometimes minimize or dismiss the risks. And as soon as we stray from the actual facts, our advocacy is on shaky ground.

10 VEGAN DIET DANGERS – By Catherine,

Definition: vegan diets exclude all animal products including meat, eggs, seafood, dairy products, and honey.

  1. HISTORICALLY, THERE ARE WIDE-SPREAD CULTURES THAT HAVE THRIVED BY SUBSISTING OFF OF ANIMAL-FREE DIETS. Gleaning dietary wisdom from those who have come before you is one of the best ways to learn about health. Along with that goes eating foods that people have been consuming for generations. The link between a diet low in animal foods (thus low in fat-soluble vitamins) and tooth decay.
  2. PEOPLE OFTEN TURN TO VEGAN DIETS BECAUSE THEY HAVE TROUBLE DIGESTING MEAT AND DAIRY PRODUCTS AND HAVE OTHER ISSUES LIKE FATIGUE, INFLAMMATION, ACNE, BLOATING, AND WEIGHT GAIN. Intolerance to certain foods does not mean there is a problem with that particular food group per se, but it does indicate imbalances within the body, which can cause weaker digestive function (such as slowed metabolism and sluggish thyroid function). Some people tend to gravitate toward a vegan diet because the included foods are “easier” to digest due to poor digestive juices. Eliminating these “problematic foods” completely and permanently only avoids the problem, instead of getting at the root issue, which is working to re-balance the body to regain tolerance of a wide variety of foods.
  3. THE BEST DIETS ARE THOSE WITH THE GREATEST VARIETY OF NUTRIENTS AND WITHOUT DIETARY LIMITATIONS. Blacklisting certain food groups interferes with your body’s communication system, which causes you to ignore your body’s cravings by placing certain types of food off-limits. The more you ignore your cravings the more they become needs and desires that cannot be ignored.
  4. VEGAN DIETS TEND TO BE LOW IN HIGH-QUALITY PROTEIN (AND LOW PROTEIN DIETS CAN INCREASE TOXICITY). One thing that happens in the vegetable diet, heavily based on [the] cabbage family, or beans, lentils and nuts, these proteins, in quality, rank about 15 times lower than the highest quality protein.  And so even though a person might think they’re eating nothing but protein rich foods, beans, and nuts, their quality is so low that their liver simply can’t respond to the thyroid. To counterbalance this, processed plant proteins (protein powders and meat substitutes) are commonplace; further contributing to nutritional deficiencies. According to a recent study, vegans and vegetarians also have lower sperm count and mobility! Long-term vegan diets tend to impair liver detoxification pathways leading to toxicity. Protein deficiency itself contributes to the harm done by toxins, since the liver’s ability to detoxify them depends on adequate nutrition, especially good protein.
  5. PLANT FOODS DON’T CONTAIN REAL VITAMIN A, ONLY THE PRECURSORS THAT REQUIRE CONVERSION. Real vitamin A, called retinol is only found in animal foods. Plant foods contain vitamin A precursors, such as beta-carotene that requires conversion into real vitamin A by the liver and intestines if conditions are right. However, some gene mutations can decrease one’s ability to make this conversion by up to 90%! Aside from genetic mutations that can impact one’s ability to get real vitamin A from plant foods like carrots and sweet potatoes, there are also non-genetic factors such as poor gut health, low thyroid function (will slow the conversion of beta carotene to vitamin A), liver disease, and nutritional deficiencies that can greatly reduce your body’s ability to make this conversion. As a little reminder, vitamin A is extremely important for thyroid function, hormone production, fertility, a healthy immune system, eye health, and fighting fatigue.
  6. PLANT-BASED DIETS CAN DECREASE DIGESTIVE JUICES. Protein stimulates the production of HCL (hydrochloric acid) in your stomach to break down proteins. Proper digestion begins with strong stomach acid production that sets the stage for the pH driven digestive process. Without regular and healthy stimulation of digestive juices, your digestion weakens and fewer nutrients are able to be absorbed in your body.
  7. DIETARY DOGMA THAT IF IT’S NOT WORKING FOR YOU, YOU’RE DOING IT “WRONG.” Immersion in any dietary paradigm can be very powerful, and the vegan community is no exception. The side effects are wide ranging and in order to continue on the vegan diet you must make excuses for the side effects or reason away the cause.
  8. BECAUSE OF THE BODY’S ABILITY TO ADAPT TO ANY TYPE OF FUEL (FOR SURVIVAL), IT OFTEN TAKES TIME TO SEE THE NEGATIVE EFFECTS OF THIS WAY OF EATING. Due to the body’s incredible ability to adapt, the decline of health due to a vegan diet is often slow and gradual. This can make it very difficult to detect. At first, you may not notice the lack of fat soluble nutrients you’re getting (particularly retinol and K2) and that a protein deficiency is hurting your health. Because your body will first exhaust your “nutritional bank account,” it may be many months or years until nutrient deficiencies cause impaired detoxification, thyroid issues, and/or hormonal imbalance.
  9. VEGAN DIETERS OFTEN FAVOR SOY PRODUCTS. Since protein is scarce when you avoid animal products, soy products like edamame, tofu, soy protein powder, and tempeh are often dietary staples. The reality is that soy protein is very difficult to digest, thyroid suppressive and estrogenic due to phytoestrogens. It also contains high levels of phytic acid that cause less assimilation of nutrients, as well as contain trypsin inhibitors that can interfere with digestion.
  10. VEGAN DIETS CAN BE HEAVY IN NUT CONSUMPTION. In an effort to increase dietary protein and calories, nuts are often adopted to form a more significant part of the diet. But there are major downfalls to heavy nut consumption. Nuts are very hard to break down, especially for those with low stomach acid. They are also very high in polyunsaturated fats, contain enzyme inhibitors, and include phytic acid that blocks the absorption of minerals.

Yes: Cut Animal-Based Protein – By Dr. T. Colin Campbell

I was raised on a dairy farm. I milked cows until starting my doctoral research over 50 years ago at Cornell University in the animal-science department. Meat and dairy foods were my daily fare, and I loved them. When I began my experimental research program on the effects of nutrition on cancer and other diseases, I assumed it was healthy to eat plenty of meat, milk and eggs. But eventually, our evidence raised questions about some of my most-cherished beliefs and practices.

Our findings, published in top peer-reviewed journals, pointed away from meat and milk as the building blocks of a healthy diet, and toward whole, plant-based foods with little or no added oil, sugar or salt.

My dietary practices changed based on these findings, and so did those of my family. So, what is this evidence that has had such an impact on my life?

In human population studies, prevalence rates of heart disease and certain cancers strongly associate with animal-protein-based diets, usually reported as total fat consumption. Animal-based protein isn’t the only cause of these diseases, but it is a marker of the simultaneous effects of multiple nutrients found in diets that are high in meat and dairy products and low in plant-based foods.

More than 70 years ago, for example, casein (the main protein of cow’s milk) was shown in experimental animal studies to substantially increase cholesterol and early heart disease. Later human studies concurred. Casein, whose properties, it’s important to note, are associated with other animal proteins in general, also was shown during the 1940s and 1950s to enhance cancer growth in experimental animal studies.

Casein, in fact, is the most “relevant” chemical carcinogen ever identified; its cancer-producing effects occur in animals at consumption levels close to normal—strikingly unlike cancer-causing environmental chemicals that are fed to lab animals at a few hundred or even a few thousand times their normal levels of consumption. In my lab, from the 1960s to the 1990s, we conducted a series of studies and published dozens of peer-reviewed papers demonstrating casein’s remarkable ability to promote cancer growth in test animals when consumed in excess of protein needs, which is about 10% of total calories, as recommended by the National Research Council of the National Academy of Sciences more than 70 years ago.

One of the biggest fallacies my opponent presents is that a diet including meat and dairy products is the most efficient way of giving the body the nutrients it needs with a healthy level of calories. Plant-based foods have plenty of protein and calcium along with far greater amounts of countless other essential nutrients (such as antioxidants and complex carbohydrates) than meat and dairy.

Higher-protein diets achieved by consuming animal-based foods increase the risks of cancer, cardiovascular diseases and many similar ailments, caused by excess protein and other unbalanced nutrients as well. It’s also worth noting that the government recommendations for certain population groups to increase their protein and iron consumption come from the U.S. Department of Agriculture, an agency long known to be subservient to the meat and dairy industries.

The dairy industry has long promoted the myth that milk and milk products promote increased bone health—but the opposite is true. The evidence is now abundantly convincing that higher consumption of dairy is associated with higher rates of bone fracture and osteoporosis, according to Yale and Harvard University research groups.

Some of the most compelling evidence of the effects of meat and dairy foods arises when we stop eating them. Increasing numbers of individuals resolve their pain (arthritic, migraine, cardiac) when they avoid dairy food. And switching to a whole-food, plant-based diet with little or no added salt, sugar and fat, produces astounding health benefits. This dietary lifestyle can prevent and even reverse 70% to 80% of existing, symptomatic disease, with an equivalent savings in health-care costs for those who comply.

By contrast, any evidence that low-fat or fat-free-dairy foods reduce blood pressure is trivial compared with the lower blood pressure obtained and sustained by a whole-foods, plant-based diet.

No: It’s a Question of Balance – By Dr. Nancy Rodriguez

For years a wealth of scientific research has supported the idea that healthy nutrition begins with a balanced diet consisting of the basic food groups: fruits, vegetables, grains and protein and dairy. Each group offers nutrients that are essential to our health. Experts agree that the most important thing to remember when considering a vegetarian or vegan lifestyle is that essential nutrients removed from the diet with the elimination of meat or dairy need to be obtained from other foods.

Individuals who stop eating meat and dairy products are at risk of not getting enough calcium, vitamin D, protein, vitamin B12, zinc and iron in their diets—all nutrients that come mostly from food products derived from animals.

What happens then? Insufficient calcium and vitamin D can compromise bone structure. Lack of zinc can hinder growth in children. B12 and iron assist production of red blood cells, which deliver oxygen throughout the body. Proteins are essential for building and maintaining muscle and keeping our brains healthy. And animal proteins provide all the essential amino acids, nutrients our bodies cannot make on its own.

Including dairy and meat in a balanced diet can be an important way to get essential nutrients without excess calories—a key consideration given concerns about our overweight and undernourished nation. Our average daily consumption of dairy products, for example, provides more than half of the recommended daily amount of calcium and vitamin D in our diets, for only one-tenth of the calories. A three-ounce serving of beef has less than 10% of the calories in a typical 2,000-calorie-a-day diet while supplying more than 10% of the daily value for 10 essential nutrients.

Contrary to popular belief, Americans aren’t eating too much protein. According to Economic Research Service data from the U.S. Department of Agriculture, the daily caloric contribution of flour and cereal products increased by about 200 calories per person from 1970 to 2008, compared with only a 19-calorie increase from meat, eggs and nuts.

The Dietary Guidelines (the U.S. government’s science-based nutritional recommendations, compiled and issued every five years) have noted that some Americans need more protein, and that adequate consumption of iron and B12 (both found in lean meat) is a concern for specific population groups. The Dietary Guidelines are founded on evidence-based, peer-reviewed scientific literature, and take into account the entire body of research, not just a single study.

Proponents of a vegan diet paint a grim picture of the effects of animal protein on human health. But the effects of powdered, isolated casein on rats tells us very little about what traditionally consumed forms of milk will do to humans. And it tells us nothing that can be generalized to all “animal nutrients.” Casein is one of many proteins found in milk and is recognized around the world for its nutritional quality.

It is simply untrue to suggest that animal protein causes cancer. The American Cancer Society, along with other leading health organizations, emphasizes that the effects of foods and nutrients need to be considered in the context of the total diet. Research from many sources shows that other factors, such as not smoking, responsible alcohol consumption, maintaining a healthy weight and regular physical activity, are much more important to reducing cancer risk than eating or avoiding any individual food.

There is scientific evidence that low-fat or fat-free dairy and lean meat, as part of a balanced diet, produce specific health benefits such as reducing blood pressure. Fat-free, low-fat and reduced-fat options are widely available, as are lactose-free milk and milk products. Many of the most popular beef cuts are lean, including top sirloin, tenderloin, T-bone steak and 95% lean ground beef.

Finally, contrary to my opponent’s assertions, dairy’s role in strengthening bones has long been established by the nutrition and science community. Don’t take just the Dietary Guidelines’ word. Dozens of randomized, controlled, clinical trials—the gold standard in research—have demonstrated that calcium and dairy products contribute to stronger bones. These trials far outweigh any observational studies which, by their very design, cannot show a causal relationship between eliminating meat and dairy foods and a subsequent improvement in health.

The Risk of No Red Meat Diets – by CHRIS DINESEN ROGERS, Oct 03, 2017

Vitamin Deficiencies: You may find that eliminating your consumption of red meats puts you at risk for vitamin deficiencies, especially if you are a vegetarian. Dietary vitamin B12 is found primarily in animal sources such as red meat, poultry and eggs. This vitamin is essential for red blood cell formation and a healthy metabolism. If you don’t get adequate amounts, you may fatigue easily and develop anemia, according to the Office of Dietary Supplements from the National Institutes of Health.

Protein Intake: Another diet concern involves protein intake. Not all proteins are created equal. Animal proteins like red meat are considered complete proteins which contain all of the essential amino acids, explains the Centers for Disease Control and Prevention. Plant sources do contain protein, but you will need to eat a variety of foods in order to make sure you are getting all of the building blocks of protein. An adult woman requires 46 g of protein each day.

Effects: The effects of a no red meat diet may result from the consequences of nutritional deficiencies. You may experience weight loss or muscle wasting if your diet does not contain enough protein. While reducing fat in your diet can be healthy, you still need to consume no less than 20 percent of your calories from healthy fat sources such as lean red meat. Otherwise, you may increase your risk of other dietary deficiencies such as vitamin E, warns the U.S. Department of Health and Human Services.

Health Risks: One concern some people may have with red meat consumption is its effects on health risk factors. A 2010 study published in the journal “Circulation” found that red meat consumption did not increase the risk of developing coronary heart disease or diabetes mellitus. Rather it was the consumption of processed meats which showed a higher incidence of these health conditions. If you’ve given up meat for health reasons, you may be depriving yourself of a highly nutritious food.

Guidelines: To gain the health benefit of red meat consumption, you can simply limit your intake of red meat to just a few times a month. You can also choose lean sources rather than full-fat red meats. Switching from regular ground beef to extra lean will reduce your fat intake by over one-half, explains the U.S. Department of Health and Human Services. If you choose to give up red meat, you will need to make other dietary changes in order to avoid the consequences of nutritional deficiencies, such as including other protein sources like tofu, beans and nuts.

The Negative Effects of Vegetarianism – by LYNNE SHELDON, Oct 03, 2017

Vegetarianism can be a healthy way to eat, provided that you design your meals carefully to give your body all the nutrients it needs. If your vegetarian diet lacks certain vitamins and minerals, you may develop deficiencies that can be damaging to your health and even life-threatening. Consider consulting with a nutritionist to come up with a meal plan, and discuss any changes with your doctor before making them.

Iodine: Your metabolism is regulated by hormones in your thyroid, and these require iodine to function properly. The function and maintenance of your heart, brain and kidneys also depend on this mineral. Seafood is the best source of iodine, though it can also be found in dairy products and kelp. Being a vegetarian, especially one who also excludes dairy, can put you at risk for developing an iodine deficiency, which can lead to side effects like hypothyroidism and goiter.

Vitamin B12: helps your body produce red blood cells. However, this vitamin occurs naturally in animal products alone, so following a strict vegetarian diet can put you at risk for a deficiency, as well as increase your risk of developing anemia. Other signs of a B12 deficiency include numbness, fatigue, diarrhea, nervousness or a shortness of breath. If you have a B12 deficiency, it may go undetected for a prolonged time due to the high amounts of folate a vegetarian diet often contains. Folate can mask the signs of a B12 deficiency until the more severe symptoms, such as neurological damage, begin to occur.

Zinc: Without zinc, your immune system cannot properly function, and zinc also plays a key role in cell division and helping your body to form proteins. While zinc can be found in both animal and plant products, your body absorbs this mineral more readily through animal-based foods. Signs of a zinc deficiency may include a loss of appetite, unintentional weight loss, loss of taste or sense of smell, hair loss, poor wound healing and depression.

Solutions: While these nutrient deficiencies can be severe, you can prevent most of them fairly easily. For example, consume iodized table salt daily, since just a 1/4 tsp. contains 95 mcg of iodine, and adults over the age of 14 need 150 mcg of this mineral per day. Both vitamin B12 and zinc can be found in items like fortified breakfast cereals and milk products, and you can ask your doctor about adding supplements as well to ensure your body is absorbing these key nutrients.

Precautions When Going on a Vegetarian Diet –

Including more vegetables and other plant foods in your diet is definitely a great idea. But there are also some disadvantages to vegetarian and vegan diets that you should be aware of. Below are the downsides to having a completely plant-based diet or one that includes only little amounts of animal proteins:

Potential lack of amino acids — Amino acids are the building blocks of proteins. They help form muscle and are important for cellular health and proper metabolism. Low protein diets might cause a lack in certain amino acids, although it depends on the specific diet.

Low levels of vitamin B12 — You can only get vitamin B12 in substantial amounts by consuming meat, fish, eggs and dairy. Cutting out all of these foods can sometimes be problematic and contribute to vitamin B12 deficiency symptoms like fatigue, weakness and others. For this reason it’s recommended that all vegetarians and vegans who abstain from eating most or all animal foods take vitamin B12 supplements.

High amounts of phytic acid — Some grains, beans and legumes, such as raw soybeans, lentils and mung beans, may contain trypsin inhibitors and other “antinutrients” that can make digestion difficult and hinder nutrient absorption. These inhibitors can block key digestive enzymes, and phytic acid found in grains can keep you from absorbing calcium, magnesium, iron and zinc. However, soaking and sprouting your grains and legumes can greatly reduce phytic acid.

Overconsumption of carbohydrates — One of the most common trends I’ve found from working with hundreds of vegans and vegetarians is that they tend to overconsume carbohydrates and sugars. Eating too many carbs can cause candida and yeast overgrowth, along with weight gain. There are some who have been able to find better balance, but this can take a lot of work and planning.

Fatigue and low energy — Again, fatigue and weakness can be due to the lack of certain vitamins that we normally get from meat and fish. This includes B vitamins, zinc and others.

Potential inability to put on muscle — This may be due to the lack of certain vitamins or protein that we normally get from meat and fish.

The Healing Foods Diet says to consume about 70 percent raw plant-based foods, and 30 percent is organic grass-fed beef, organic pastured dairy, wild-caught fish, and free-range organic poultry and eggs.

The Scary Mental Health Risks of Going Meatless: Vegetarianism can come with some unexpected side effects. BY JILL WALDBIESER, December 2, 2015

More and more women are vegging out…of their minds. New research suggests that along with shedding pounds, slashing cancer risk, and boosting life expectancy, vegetarianism could come with lesser-known side effects: Panic attacks. OCD. Depression. WH investigates the puzzling blow of going meatless—and how to stay plant-based without going mental.

It’s tough to argue with the science—and with a movement that’s been endorsed by everyone from Gandhi to Beyonce. And it’s natural to assume that peak mental health and a perpetually blissed-out attitude are just two more side effects of the glowing vegetarian lifestyle.

So it was startling last year when Australian researchers revealed that vegetarians reported being less optimistic about the future than meat eaters. What’s more, they were 18 percent more likely to report depression and 28 percent more likely to suffer panic attacks and anxiety. A separate German study backs this up, finding that vegetarians were 15 percent more prone to depressive conditions and twice as likely to suffer anxiety disorders.

Even the pros find the stats confounding in a chicken-or-egg way. “We don’t know if a vegetarian diet causes depression and anxiety, or if people who are predisposed to those mental conditions gravitate toward vegetarianism,” says Emily Deans, M.D., a Boston psychiatrist who studies the link between food and mood.

How Scary Are the Mental Health Risks of Vegetarianism?: How strong is the link between vegetarianism and mental illness? – Posted Dec 15, 2015

The bad news is that vegetarians and semi-vegetarians were indeed more likely that non-vegetarians to suffer from all four of the categories of mental illnesses. For example, vegetarians were twice as likely as non-vegetarians to have had an anxiety disorder and five times more likely to have suffered from an eating disorder. The frequency of mental illness among the semi-vegetarians generally fell between the vegetarians and the non-vegetarians.

The researchers found substantial links between vegetarianism and psychiatric illness. But does this support the claim of the Women’s Health Magazine headline – that giving up meat CAUSES mental illness? Not at all. The researchers pointed out three potential explanations of the connection between diet and mental disorders.

Hypothesis 1: Vegetarians diets can cause poor mental health by affecting brain chemistry.

Hypothesis 2: Psychological factors such as personality traits make some people prone to choose a vegetarian life style and also predisposes them to mental health problems.

Hypothesis 3: The decision to give up meat is, in some cases, a consequence of a mental disorder, for example, hypochondria.

The Vegan Brain: Plant-based diets, micronutrients, and mental health – Posted Sep 30, 2017

Vitamin A is important to many aspects of brain function including vision, learning, and memory. Contrary to popular belief, plant foods are lousy sources of vitamin A. In fact, they contain no vitamin A at all! Instead, they contain carotenoids, which we must then convert into retinol, the form of vitamin A our bodies can use. This is 12 to 24 times more difficult than obtaining retinol from animal foods.

Vitamin D3 is important in brain growth and development, regulates calcium levels within the brain, helps protect brain cells from damaging oxidation, and supports the health of the hippocampus (the brain’s memory center). The form of vitamin D our bodies need is vitamin D3 (cholecalciferol). We can make Vitamin D3 from sunshine or obtain it from animal foods. The form of vitamin D found in plant foods is vitamin D2 (ergocalciferol). Our bodies can convert some D2 to D3, but D2 is less potent, doesn’t last as long in the bloodstream, and may be harder to store in our body fat for rainy days and dark winters. If we spend enough time in the sun, we don’t need to obtain any vitamin D from our diet at all, yet many people (regardless of chosen diet) are deficient. Most studies have found that vegans have lower blood levels of vitamin D3 and are more likely to drop to deficient levels during winter months than omnivores.

Vitamin K2: When most people think of vitamin K they think of vitamin K1, which is abundant in many plant foods, but vitamin K2 is just as important and often overlooked. Vitamin K2 is confusing because it comes in many forms, but the essential form we need is called MK-4. In the brain, MK-4 is required to build critical cell membrane components called sphingolipids, as well as to support the overall health and function of brain cells. The MK-4 form of vitamin K2 only exists in animal foods. The body can convert a little bit of K1 into MK-4, but not nearly enough to fully meet our needs. Therefore, savvy vegans turn to natto (fermented soy), which contains a bacterial form of vitamin K that our bodies can turn into MK-4 a little more easily.

Vitamin B12 (Cobalamin): Without this essential vitamin, the body cannot synthesize DNA, RNA, red blood cells, or myelin (the substance that wraps around and insulates our brain circuitry). Not surprisingly, B12 deficiency causes a whole host of serious psychiatric problems, including depression, psychosis, memory problems, mania, and changes in behavior or personality. Vegan diets contain virtually no vitamin B12, and severe, prolonged B12 deficiency is fatal. Most vegans and vegetarians are aware of this danger and either take supplements or consume fortified yeast (unfortified yeast doesn’t naturally contain any vitamin B12). Unfortunately, deficiency is still far more common than it should be, with some studies finding that as many as 86% of adults (regardless of chosen diet) are deficient. Researchers report wide ranges of values, but overall, vegetarians tend to have lower B12 levels than omnivores, and vegans on average tend to have the lowest B12 levels.

Vitamin B1 (thiamin), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin) and B9 (folate) all work together to extract energy from food, build vital molecules, and regulate the metabolism of neurotransmitters such as serotonin. The brain is a high-energy organ, so even temporary, mild deficiencies of a single B vitamin can significantly disrupt normal brain function. All of the B vitamins except for B12 can be found in plant foods, yet some studies find that vegans are more likely to be deficient in vitamin B3 (niacin), B6 (pyridoxine), and B2 (riboflavin). Riboflavin seems to be the one that vegans need to pay the most attention to, as studies have more consistently shown higher risk of deficiency of this B vitamin in vegans compared to vegetarians and omnivores. All three of these B vitamins can be found in plant foods, but often in smaller amounts than animal foods, so it can be challenging to obtain adequate amounts from a vegan diet unless great care is taken to include just the right mixture of foods

Iodine: Lack of iodine, particularly in early life, stunts body and brain growth. Iodine is a required building block in thyroid hormone, which is critical in brain development and maintenance. Iodine deficiency affects two BILLION people, and is the most common preventable cause of intellectual disabilities in the world. Most plant foods are quite low in iodine compared to many animal foods. Although vegans are generally more likely to have iodine deficiency compared to vegetarians and omnivores, iodine deficiency in the United States is uncommon due to the widespread use of iodized salt.

Iron: When people think of iron deficiency, they think of anemia (lower numbers of red blood cells in the circulation), but the truth is that the brain needs iron just as much as red blood cells do. Iron is required for neurotransmitter production (serotonin, dopamine and norepinephrine), generation of brain energy, hippocampal function (memory!), cell signaling, and infant brain development. Many plant foods are lower in iron than animal foods, and to make matters worse, plants contain a form of iron that is far more difficult to absorb than heme iron, the form found in animal foods. Most vegans and vegetarians have about the same amount of iron in their blood as omnivores do, but their total body iron stores (how much they have in reserve) do tend to be lower.

Zinc: The brain requires zinc for serotonin synthesis, vitamin B6 activation, and cell signaling. Plant foods are far lower in zinc than animal foods. Zinc deficiency is much more common among vegans than iron deficiency, and yet gets far less attention. A 2017 Swiss study found that 47% of vegans had inadequate zinc levels compared to only 10% of omnivores. Some clinical trials show that combining zinc supplements with antidepressants improves outcomes, and there’s even been one randomized controlled trial demonstrating that zinc supplements alone can reduce severity of depression symptoms.

Essential Omega-3 Fatty Acids: DHA and EPA – DHA and EPA are the forms of essential omega-3 fatty acids required for brain and immune system function. The brain is extremely rich in DHA, which is required to make myelin (the material that wraps around nerve cells, insulating brain circuits), and to keep cell membranes fluid and flexible enough to pass neurotransmitters back and forth. DHA is critical in the formation of healthy synapses (connections between brain cells), therefore infant brains require lots of DHA to develop properly. In short, DHA plays a “unique and indispensable role” in the “cohesive, organized neural signaling essential for higher intelligence” [Dyall SC 2015 Frontiers in Aging Neuroscience 7(52)]. Vegan diets contain absolutely no DHA or EPA, and vegetarian diets contain only small amounts from eggs and dairy. In comparison to omnivores, DHA and EPA levels can be about 30% lower in vegetarians and more than 50% lower in vegans. This is because the form of omega-3 (ALA) found in plant foods is very difficult for the body to convert into DHA. At best, women convert only about 9% of the ALA they consume into DHA, whereas men convert a dismal 0-4%.

Do Vegans Have Low Brain Cholesterol? – We are often told that one advantage of a vegan diet is that all plant foods are naturally 100% cholesterol-free. Yet the brain (and indeed, every cell in the human body) requires cholesterol to function properly. Although the brain represents only 2% of total body weight, it contains 20% of the body’s cholesterol. Cholesterol is required for brain cell membrane structure and function, and is a vital component of myelin (brain cell insulation).

The science is clear on this point: unsupplemented vegan diets pose great danger to brain health. The right conclusion to this debate is that yes, a diet and your mental state are connected. However, it’s true for ANY diet as whether you eat or don’t eat meat doesn’t matter when your meal plan is unbalanced. If you want to stay strong and keep your mind and body healthy, you must stick to a healthy diet full of all the nutrients you need.

Less than 1 percent of the U.S. population is vegan. While many people try it out, most go back to eating animal products. But the religiously committed seem to inevitably wind up preachy, angry or silly.

What exactly might explain this bizarre behavior?

Consider one theory: Our bodies require Vitamin B12 for proper brain function. Vitamin B12 is only found naturally in animal products. It’s possible to get it through supplements, but as many as 92 percent of vegans are deficient in B12, according to the Daily Mail. (Vegans are also at risk of deficiencies in iron, calcium and omega-3s.)

And as one nutritionist recently explained to the paper, Vitamin B12 deficiency can lead to “fatigue, megaloblastic anemia, early dementia, increased risk of heart disease, nerve dysfunction, forgetfulness, lack of coordination, and psychiatric disorders.”

The “Diagnostic and Statistical Manual of Mental Disorders” suggests, “A mental disorder is a syndrome characterized by clinically significant disturbance in an individual’s cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning.” Could veganism fit the bill?

When people rebel against humans’ fundamental nature, problems can arise. Just as we have circadian rhythms and need oxygen, perhaps it’s simply in our nature to eat animal protein. Humans have eyes that face forward, like a predator, not to the side like an herbivore. Scientists believe that a meat-based diet contributed to brain growth in humans over time. Herbivorous food wasn’t calorie-dense, and so large stomachs were required (think of a cow) to plow through roughage. Meat, on the other hand, provided plenty of energy to grow our brain. Meat made us smarter. And given that researchers have pointed to a B12 deficiency as leading to a higher risk of brain shrinkage later in life, it’s only smart to accept ourselves for what we are.



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