- 5 Reasons Why You Don’t Need Vitamin Supplements
- Studies Show That Supplemented Vitamins Do Not Always Decrease Incidence Of Disease
- Using Multi-vitamins & Vitamin Supplements May Increase Your Risk Of Disease
- Artificial Vitamins and Anti-Oxidants May Inhibit The Benefits of Exercise
- Fruits & Vegetables Today Are Not Drastically Lower in Vitamins and Minerals Than Several Years Ago So You Need Vitamin Supplements To Replace Them
- Vitamin Supplements Are Not Needed To Prevent Deficiencies
5 Reasons Why You Don’t Need Vitamin Supplements
Estimates are that anywhere from 25% to 50% of American adults have taken some form of vitamin supplement over the past year, with sales in the United States reaching a little over $13 billion for vitamin and mineral supplements in 2006, of which $5.4 billion was for multi-vitamins.[1,3,18,19] Popular since the 1940’s when they were first artificially synthesized, savvy marketing on the part of the supplement industry has made it such that today most members of the general public believe vitamins to be a quick and inexpensive to improve their health, increase their energy and make up for bad eating habits. Those who work out regularly swear by them and extensive marketing has propagated the belief that a multi-vitamin a day serves as somewhat of an insurance policy against getting sick, especially among adherents of alternative medicine and those keen on avoiding Western medicine as much as possible. However, as ubiquitous as these vitamin supplements have become, with the exception of pregnant women, acquired immune deficiency syndrome patients, older populations and those on meat restricted diets who are advised to take specific supplements for special purposes[34, 35], there is little in the way of credible and unbiased research to show that vitamin supplements have any effect whatsoever in improving your health and are not required. Numerous studies show that most supplemented vitamins are not just ineffective but may not be healthy at all.
Vitamins and minerals are essential nutrients that our bodies need for normal growth and optimal health, however the basic problem with vitamin supplements is that they cannot replicate all the ingredients found in whole foods, nor can they make up for poor lifestyle and eating habits. Not all vitamin supplements are suspect, as there is substantial evidence demonstrating that vitamin D and calcium can increase bone density in postmenopausal women and folic acid supplementation can reduce birth defects when taken by pregnant women.  Aside from these and other very specific populations there is no need for vitamin supplementation in the general population- athletes included. Throughout history we have been able to meet our vitamin and mineral needs by consuming available plant and animal foods. With the exception of human breast milk no one food is better than another or absolutely necessary for optimal health, but by mixing and matching our foods we are naturally able to create healthy diets that not only meet our nutrient needs but also suit our tastes, cultural, religious and ethnic preferences. In this article we outline five strong and science based reasons why it is in your best interest to rely on vitamins from fresh fruit, vegetables, whole grains, beans and legumes as opposed to getting them from artificially made supplements.
One of the main selling points of supplemented vitamins is the idea that they supply much needed anti-oxidants that help prevent disease and many vitamin takers are routinely held up as perfect examples of robust health. Several studies have shown a correlation, (very important word), between people who regularly take vitamins and a significantly reduced incidence of chronic disease when compared to those who don’t. Note the word ‘correlation’ as all of those studies which are often cited by the supplement industry have one very fundamental flaw. You see, the act of regularly taking a vitamin supplement is associated with several other characteristics. People who take vitamin supplements regularly are less likely to be smokers, less likely to abuse alcohol, are more likely to exercise, more likely to eat in moderation and are also more likely to be well educated and in a high income bracket. A subgroup of society who are healthier than the rest of the population regardless of whether or not they take vitamin supplements.
We know without a doubt that regular consumption of naturally occurring foods high in the very vitamins, minerals and anti-oxidants that vitamin supplements contain do have a beneficial effect in reducing the incidence of cancer, heart disease and other metabolic related illnesses, however peer reviewed studies show that man-made vitamins do not seem to have the same effect. In 2009 researchers from the Women’s Health Institute concluded a 15 year study of methods to prevent heart disease and cancers in post-menopausal women, a study that was monumental in its scope, observing a total of 161,808 women using vitamin supplements for eight years and then checking in on them for several years afterwards. The study’s conclusions were not very positive for proponents of vitamin supplement use as researchers noted that there was ‘convincing evidence that multivitamin use has little or no influence on the risk of common cancers, CVD or total mortality.’
Another recent meta-analysis of over 27 studies encompassing a total of 355,080 women had a similar finding- namely that multivitamin use had no effect on decreasing the risk of breast cancer. A study on the intake of the popular vitamins E and vitamin C by 15,000 male physicians over the course of ten years found absolutely no health benefits as well. These results don’t come from small scale, industry-sponsored, single nutrient research but from credible and peer reviewed scientific study conducted over several years. Nevertheless, vitamin supplement manufacturers do everything to distract us from the facts, with claims that their vitamins are more natural than other brands used in the studies or that they have some proprietary blend that magically makes their product as effective as real food. Great marketing, but poor on truth and it’s important to not be distracted by the cacophony of misinformation. What is more alarming is that several other studies have shown that some vitamin supplements may actually increase your risk of developing certain diseases.
One of the first warnings against the use of vitamin supplements came in 2005 with a study finding that a high percentage of men with prostate cancer who were white, well educated, active and living healthy lifestyles had one thing in common- they regularly took vitamin supplements. Following up on this was a trial of 295,344 men enrolled in the National Institutes of Health Diet & Health Study. The trial found that while vitamin supplements didn’t seem to increase the risk of localized prostate cancer, those who took them frequently had, in some cases, twice the risk of developing advanced prostate cancer. Frequent users of vitamin supplements were also were more likely to die from prostate cancer than those who never took vitamin supplements at all- a sobering statistic to say the least. Positive cancer associations with excessive vitamin use were strongest among men with a family history of prostate cancer or among those who took individual micronutrient supplements such as selenium, beta-carotene and zinc.
The use of individual vitamins as antioxidants has also raised concerns in the medical community after one of the most comprehensive reviews of randomized trials of 232,606 adults taking supplemented beta-carotene, vitamin A, vitamin C (ascorbic acid), vitamin E and selenium. Researchers found that not only did participants not receive any health benefits from using vitamin supplements, but that supplemented intake of beta carotene, vitamin A, and vitamin E appeared to increase mortality rates. More studies were recommended to research the possible links between supplemented vitamin C and selenium and higher rates of mortality but in 2008 a study on the ability of vitamin E and selenium to lower the risk of prostate cancer was halted amidst fear of potential harm to participants. The study was stopped after it was found that supplemented vitamin C in certain doses may do more harm than good as it may have a role in protecting cancerous cells.
Vitamin C is perhaps the most popular supplemented individual vitamin with a strong belief that it can help reduce the severity of symptoms of the common cold- a claim that studies have found to be due only to the placebo effect as those taking vitamin C and those not taking vitamin C had the same outcomes depending on whether they believed they were taking vitamin C or not. The placebo effect is a remarkable phenomenon that many supplement manufacturers rely on for testimonies to the efficacy of their products, [See my article on the Placebo Effect On Sports Performance], however studies also find that an increase in supplemented vitamin C is also associated with an increased risk of kidney stones and iron related disorders. Even more alarming, Patients with iron overload and healthy people of Northern Africa and those of North African descent often have abnormal low contents of ascorbic acid in their blood and tissues. For them, taking a high dosage of supplemented vitamin C in the absence of desferioxamine, which is used to treat iron poisoning, can be deadly. Many Caucasians have a gene disorder for iron overload called hemochromatosis and ingestion of high amounts of supplemented vitamin C can lead to deleterious and lethal consequences. Those with a gene disorder called thalassemia, which is common among those of Mediterranean descent have died after ingestion of high levels of vitamin C. It gets worse. A recent control study in the United Kingdom found that high circulating blood levels of Vitamin B(12) and (in cohort studies) folate were associated with an increased risk of prostate cancer  casting severe doubts on recommendations for the use of vitamin B12 supplements and folic acid in men. Another study found that long term use of zinc from multivitamins or single nutrient supplements was associated with a doubling of the risk of prostate cancer. Adding to the growing evidence for an unfavorable role of vitamin supplements in general on prostate cancer carcinogenesis.
It doesn’t end there; a study published in the Journal of the American Medical Association concluded that, ‘in patients with vascular disease or diabetes, long-term supplementation with 400 IU/day of vitamin E may increase the risk for heart failure.’ It isn’t all bad feedback on vitamins as there is compelling cause and effect data linking the use of folic acid supplementation with consistent and significant reductions in adverse pregnancy outcomes in women, even though folic acid supplements may have adverse effects on men. Vitamin B12 is often prescribed for vegans and those who do not eat meat as this vitamin only occurs in animal sources and many on such diets are indeed vitamin B12 deficient. However the link between B12 supplementation and prostate cancer risk is not fully understood and vegans in developed countries tend to forget that long before vitamin B12 supplementation, human populations were able to survive without eating meat. Before today’s world of pesticide treated fruits and vegetables, (and yes- even organic produce is treated with pesticides), we ate a diet rich in fruits and vegetables- with some of them coming from wild uncultivated sources that contained tiny insects and larvae. These small particles of animal matter do not constitute useful protein sources but served as an important source of vitamin B12 and a supplemental source of essential amino acids which tend to be low on a vegan diet.[35,36] It might sound strange for those living in the United States to think of tiny bits of insects in your produce, but growing up in the islands it was something you never thought twice about and it is how we ate for hundreds of thousands of years. It also explains to a large degree how apes and other mammals are able to meet their B12 requirements without the direct consumption of animal proteins.
Even the vitamins that may be beneficial can be harmful when taken in large doses- to quote Paracelsus- it is the does that makes the poison and this is no truer in the case of vitamins. Calcium may help improve bone strength, but if too much is ingested it can promote the buildup of plaque in the arteries , high levels of vitamin A can cause osteoporosis while high levels of vitamin D can dangerously elevate calcium levels. In addition to the dangers mentioned above, continued high intake of vitamin C can increase the risk of kidney stones and red blood hemolysis- which can lead to anemia. High supplemented vitamin C intake by pregnant women has also been shown to increase the risk of dental decalcification in infants and the risk of them being born with vitamin C deficiencies. Chronically high vitamin C intake may also adversely affect estrogen levels. It’s a complex issue but not one where the use of supplemented vitamins seem to make sense, especially given the safer alternative of consuming a diet high in fresh fruits vegetables which can supply all the vitamins and minerals you need without he risk of easily overdosing.
It is estimated that over 90% of athletes take some form of dietary supplementation, creating and following their own prescriptions or the prescriptions of self-designated coaches and trainers despite established recommendations regarding the risks connected with prolonged and excessive intake of specific vitamins and minerals.[21,22] Regular physical activity as well as prolonged and or intensive exercise have well documented beneficial effects on health outcomes including a reduction of the risk of cancer, heart disease, osteoporosis, diabetes and other chronic diseases. However, exercise is one of the main causes of oxidative stress and many athletes believe that they need extra vitamins to compensate for this and the loss of minerals through sweat during exercise. While it does (on the surface) sound like good idea, there has however been no evidence to justify the massive intake of vitamin and mineral supplements among those who regularly exercise.[24,25]
It should be noted that while naturally occurring vitamins and minerals in foods are required for normal growth, maintenance and repair of muscle tissue, large amounts can be toxic and high levels of any single nutrient being ingested into our bodies is an inherently unnatural occurrence.[21,22] Our bodies are very much a product of our evolutionary environment and under natural conditions, it simply isn’t possible to come across large amounts of any single nutrient as they invariably coexist with a host of other valuable micronutrients, macronutrients, phytochemicals, trace minerals and compounds in ratios that our bodies have adapted to over the span of millions of years. Not surprisingly studies have found that high levels of single nutrients can actually interfere with the absorption and the functions of other nutrients and also adversely affect the way our bodies benefit from the stress of exercise.[26,27,28] Exercise is essentially a stress and the health benefits of exercise are our adaptations to this stress- a cycle that is as old as our very species. [See my article- How Muscles Get Bigger & Stronger] Oxidative stress and the muscle damage that comes as a result is what triggers our bodies’ beneficial muscle adaptation to exercise.[26, 27, 28] Recent research has also shown that some of the health-promoting effects of exercise are also directly related to oxidative stress as exercise-induced free radical production appears to promote insulin sensitivity and helps to prevent type 2 diabetes.[31,13] Taking anti-oxidant supplements interfere with this cycle and may actually delay muscle recovery and reduce the positive effects of exercise.
A study published in 2009 evaluated the effects of a combination of vitamin C (1000 mg/day) and vitamin E (400 IU/day) on insulin sensitivity in exercising men and researchers found that artificial supplementation with antioxidants inhibited the beneficial reduction in insulin sensitivity usually produced by exercise. Other studies have reported similar findings- that supplementation with vitamin C, vitamin E and other antioxidants, or antioxidant mixtures can reduce symptoms or indicators of oxidative stress while having no beneficial effect on performance. The studies’ researchers all concluded that until more studies have fully documented the long term safety and effects of supplemented antioxidants, physically active individuals should avoid them and instead ingest a diet of foods rich in naturally occurring antioxidants.[14, 15.16] A recommendation that flies in the face of the practices of millions of athletes but one that they should take to heart nonetheless.
Fruits & Vegetables Today Are Not Drastically Lower in Vitamins and Minerals Than Several Years Ago So You Need Vitamin Supplements To Replace Them
The depleted soil theory has been a popular selling point for manufacturers in the vitamin industry for years. The theory holds that soils today have been depleted by years of intensive agriculture practices so the fruits and vegetables of today contain far less nutrients than they did 50 years ago. As a result, you need a vitamin supplement to get the missing nutrients. A logical sounding argument but not exactly an accurate one. Studies have found some reduction in nutrient content in vegetables grown today as opposed to 50 years ago, but his has nothing to do with soil quality which has remained the same. So what is the real story? Well, the marked increase in American food production over the past several decades occurred as new technology developed crops that grew faster and thus produced greater yields than ever before in the history of humankind. This is one reason why we have more food at this time than ever before, however the a faster growing plant does not have as much time to acquire the same amount of nutrients from the soil or from synthesis as much as their slower growing counterparts.  The reduction in nutrients vary depending on the crop with declines found mainly in protein, calcium, phosphorus, iron, riboflavin and vitamin C. Reductions ranged from 6 % for protein, 20 % for vitamin C, 15 % for iron, and 38% for riboflavin.
This study is frequently mentioned by those marketing vitamin supplements and they conveniently omit the author’s affirmation that fruits and vegetables are still extremely high in vitamins, minerals and phytochemicals and remain our best sources of these nutrients. Valuable nutrients that are not present in vitamin supplements. The study also concluded that while there was a decline in the amount of certain nutrients in some crops, this came with the benefit of more fruits and vegetables being available for consumption in amounts that were not possible before. So while our great-grandparents would have had slightly more nutrients from fruits and vegetables they ate, today the average man or woman in a developed country can eat far more fruits and vegetables than their forefathers. This more than makes up for any nutrient reduction and is demonstrated by the fact that severe vitamin and mineral deficiencies no longer exist among populations in developed countries which is a far cry from the near pandemic levels of severe deficiencies several generations ago. Which leads to our next point:
“Deficiency symptoms have been induced only under experimental conditions and there is no convincing evidence that the ordinary diet requires supplementation with these nutrients.” Food & Drug Administration.
While hundreds of millions of people throughout the world suffer from nutritional deficiencies in developing countries because of inadequate food supplies and poverty related conditions, here in the United States and in other developed countries overt symptoms of dietary deficiencies are far less prevalent. For most Americans, while there is no arguing that the average diet high in sugar, salt, fats and refined foods is in need of drastic improvement, micronutrient deficiency to the point of severity is almost non-existent. A true deficiency of an essential vitamin or mineral tends to come with very tangible and recognizable symptoms- usually in the form of digestive, neurological or skin disorders, which is not the case for the general population of people in developed countries. Our main nutritional problems stem from the overconsumption of refined foods that can lead to obesity and a higher risk of metabolic related diseases. Vitamin and mineral deficiencies are the least of our worries today, in spite of what you may hear in the media and from studies funded by special interest groups who want you to buy vitamin supplements. A good example is a recent study that made headlines reporting that 90% of Americans are nutrient deficient. The ‘research’ found that nine out of ten Americans are deficient in 11 key nutrients including calcium, vitamin D and potassium. It sounds alarming but before you run to buy some vitamins you might want to consider two important facts. The study wasn’t reviewed or recognized by any scientific authorities on nutrition and the fact that the study was conducted by the Milk Processor Education Dairy Research Program. Not surprisingly, the study, (if you can really call it that), came with a recommendation that drinking more milk would alleviate the aforementioned deficiencies. It’s a typical industry-centered public relations campaign which is designed to looks like a scientific study, but is really just another way to make you buy more products. (Read more on industry marketing practices in The Economics of Obesity)
That being said, even though food production levels in the United States are enough to meet the energy requirements of every member of the population several times over, some Americans do not eat a proper diet because they are simply too poor to be able to afford it. As much as 20 million American adults and children go hungry and while studies have found nutrient intakes below recommended levels among groups of people living in poverty, such findings are only rarely accompanied by clinical signs of vitamin and mineral deficiencies When clinical signs of vitamin deficiencies do occur in these populations, it is usually associated with the increased nutritional requirements of pregnancy, infancy, illness, injury or as a result of drug or alcohol abuse. It would be absurd and insulting to think that a few vitamin pills would solve the problem of poverty related malnutrition as what these populations really need is access to a reliable source of wholesome foods. Yet, when vitamin supplement companies do their own self-promoting studies, they very often include the millions of Americans living on the poverty line in their statistics as people who could easily increase their low vitamin intake with their pills and powders.
Does Cooking Reduce Vitamins In Foods?
Another marketing statement used to promote the need for supplemental vitamins is the argument that cooking reduces vital nutrients in our foods that we need to replace with vitamins. If this were the case given the laws of natural selection humans would have either died out as a species several hundred thousand years ago from severe vitamin deficiencies when we began using fire to cook foods or stopped cooking. Ironically, the exact opposite is true as scientists believe fire played a major role in our survival as cooking is essential for the consumption of tubers. Cooking is essential for the conversion of the complex carbohydrates they contain to the simpler forms that humans can digest, thus allowing early humans to absorb more food energy per unit of food consumed. Our digestive system has evolved to deal with cooked foods and some researchers credit the increased nutrition from cooked plant and animal sources with the increase in brain size that made us modern humans. That being said, cooking foods isn’t a valid reason for supplementation even though it may reduce vitamin content slightly in some foods, but nowhere near enough to bring about deficiencies.
The Fitness Industry’s Role In Promoting The Use Of Vitamin Supplements
Unfortunately selling vitamins is often a major source of income for many in the health and fitness field and few are willing to jeopardize losing their commissions by speaking out against them. Vitamin and supplement distributors spend a lot of time convincing health professionals to sell their products- I get at least one requests a week. Interestingly enough, each company sidesteps the science that clearly demonstrates that vitamin products are not required for healthy individuals by saying that their vitamins are made with ingredients that are ‘more natural’, (whatever that is supposed to mean), and of better quality than what is already on the market. Keep in mind that the FDA does not monitor the manufacturing conditions of vitamin supplements so you really don’t have any guarantees that what you are buying is what is really in the bottle. That said, vitamin supplement companies can be quite persuasive and the compensation to sell them can be substantial, and it creates a legion of trainers and coaches who are trusted by consumers, pushing the use of vitamins onto their clients. It is without question a brilliant marketing strategy, but one that puts profit before public health. The magic pill ideology also takes away from the important message of eating more fruits, vegetables and natural foods while incorporating exercise into your life. Taking a pill here and there isn’t going to make you any healthier and in many cases it might do more harm than good.
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