About a month ago, you may have read some of the newspaper headlines or heard the spots on evening news that went something like, "Your Multivitamin May Be Killing You!" - or "Is This The End of Vitamins?"
Many of these (irresponsible) headlines were driven by a new analysis of data from the Iowa Women's Health Study (IWHS) published in the Archives of Internal Medicine (October 2011). The IWHS is a long-running (19 years) study that asks more than 38,000 women about their diet and lifestyle habits - questions about what they eat, what supplements they take, etc. From the newspaper headlines, you might have come away with the idea that swallowing vitamins was poisoning these women and that Iowa must be awash in dead bodies. What the analysis actually found was that older women, who supplemented with high levels of certain minerals (particularly copper and iron), when they didn't need them (because they already had normal levels of these minerals in their diets), encountered health problems, including a very slight statistical increase in mortality (so small that many researchers think the result is an error/artifact of the statistical analysis).
So, the newspaper headlines would have been more accurate if they said something along the lines of, "Older women with excellent diets should go easy on mega-dose minerals" - but, of course, headlines like that don't sell newspapers.
What the latest IWHS analysis DOES suggest to us though, is that older (postmenopausal) women, as well as most men, probably don't need to supplement their diets with iron (but we've known that for years and most multivitamin supplements are formulated with low/no iron for these population groups already). We also know that mega-doses of ANY mineral (or any nutrient for that matter) tends to be a bad idea for anyone - unless you have a known nutrient deficiency that you're trying to correct.
For example, we've known for many years that high-doses of isolated nutrients can actually cause more problems than they prevent - recent examples are beta-carotene in smokers (leading to more lung cancer) and vitamin C in cancer patients (which protects cancer cells more than healthy cells). The "take-away" message from such studies is not that supplements are "bad" - but rather that synthetic, isolated, high-dose supplements are bad in certain circumstances.
Consider another recent problematic example from the "synthetic, isolated, high-dose supplement" approach - that of vitamin E. A study published last month in the Journal of the American Medical Association (JAMA, October 2011) called the SELECT trial, found that vitamin E slightly increased the risk for prostate cancer. The type of vitamin E supplement used in the study was a high dose (400IU) of synthetic form ("dl-") of an isolated type of vitamin E (alpha-tocopherol only, which is one of eight different types of vitamin E that is found in our diets).
About half of Americans report taking at least one supplement on a regular basis - that's a lot if vitamin users. The dietary supplement industry generates about $28 billion in annual sales - which sounds like a lot of money, until you consider that just one cholesterol drug generates $9 billion yearly (Lipitor from Pfizer) and that the pharmaceutical industry spends nearly $15 billion annually just to market their products. Also consider that the most common reason for a visit to the emergency room among senior citizens is not "dangerous" vitamin supplements, but is due to commonly used diabetes pills and blood thinners (prescription drugs are a LOT more dangerous than dietary supplements). According to a new study from the Centers for Disease Control and Prevention (New England Journal of Medicine, November 2011), adverse drug events such as allergic reactions and overdoses accounted for about 100,000 hospitalizations every year in people 65 and older (99,628 drug-induced hospitalizations in 2010).
Again and again, we are finding that synthetic, isolated, high-dose supplements fail to keep us healthy and fail to prevent disease (and may actually cause cellular damage that accelerates the disease process in certain cases). Studying the health benefits - or disease-preventing effects - of dietary supplements is extremely difficult because, unlike drugs where you can study the differences between a treatment group (the drug) and a non-treatment group (a placebo), you cannot have a supplement study where the placebo group gets "zero" of the nutrient being studied (because of baseline levels of the nutrient in the normal diet). As such, you're always comparing a "low-ish" dietary level of the nutrient with a "somewhat higher" supplemental level of the nutrient - and such studies may need to be carried out for decades to tease out small differences in certain health parameters.
We know that drugs are dangerous - that's why they come with a long list of side effects and health warnings printed on a "product insert" - including the most stringent "Black Box" warning (alerting patients to serious injuries, including death) that the US Food and Drug Administration mandates be placed on the most dangerous classes of medications - antidepressants, ADHD drugs, and sleep aids.
What should you do?
Considering the latest studies (and the thousands of studies that have come before them), I still recommend the following when it comes to daily supplementation:
- Keep taking your daily Multivitamin. A balanced formula should contain:
- an adequate level of vitamin D (1,000-3,000IU of vitamin D3)
- a balanced form of natural vitamin E (30IU including all eight vitamin E isomers - tocopherols and tocotrienols)
- a balanced blend of vitamin A in pre-formed and pre-cursor (beta-carotene) forms
- RDA-levels (100% Daily Value) of most minerals in bioavailable forms (such as amino acid chelates) - except for iron in men and postmenopausal women. The exception is athletic men and women, who may require supplemental iron to replace excessive losses.
- Take extra Calcium (up to 500mg from supplements) and Magnesium (up to 250mg from supplements) if you're not getting enough from your diet (1,000mg-1,500mg of calcium and 500mg-750mg of magnesium, depending on age and gender).
- Take a daily Omega-3 supplement. Properly purified and concentrated fish oil is the most effective approach to deliver the 1,000mg of omega-3 fatty acids (EPA & DHA) recommended by most research organizations. Vegetarians can look for flax seed oil and algae-derived omega-3s, but concentrations and potency are much lower.
- Stay away from mega-doses of ANY supplement, but especially avoid mega-doses of any mineral and any antioxidant because we already have very good scientific evidence that pharmacological levels of such nutrients can cause more harm than help in the human body.
- Consider further supplementation based on individual lifestyle goals. For example, if you're an athlete, you may want a supplement to help you recover better/faster from your workouts - or if you're a busy mom, you might want a supplement to help with energy or stress levels - or if you're trying to lose weight, you might want a supplement to help control appetite and burn fat faster.
Keep in mind that our body is a collection of numerous interconnected biochemical networks - all interdependent upon one another for proper functioning. As with an army, there is no single soldier that we can target to significantly affect the performance of the entire army - we must hit multiple "soldiers" simultaneously to influence the health of the overall organism - and no approach is more multi-faceted than a dietary approach consisting of a well-balanced and varied diet (foods) complemented by a well-balanced and varied supplement regimen.
I will certainly continue taking my daily multivitamin supplement (Intense Defense) to help "provide" essential nutrients, "protect" from toxins in the environment, and "promote" fat and carbohydrate metabolism - and I encourage you to continue taking your daily multivitamin - even is it's just for nutritional "insurance" when you can't eat a perfect diet.
Thanks for reading...
Shawn M. Talbott, PhD, CNS, LDN, FACSM, FAIS, FACN