Several people have asked us to comment on recent news stories about research showing that taking vitamin pills has little if any health benefit, and in fact may be harmful in certain instances (such as for people with a cancer diagnosis). A representative article in this vein is the New York Times piece “Vitamin Pills: A False Hope?” by Tara Parker-Pope, published Feb. 16, 2009, and accessed by us online at http://www.nytimes.com/2009/02/17/health/17well.html.
Here’s our commentary, which takes its start from a key passage in the article:
NYT: In any event, most major vitamin studies in recent years have focused not on deficiencies but on whether high doses of vitamins can prevent or treat a host of chronic illnesses. While people who eat lots of nutrient-rich fruits and vegetables have long been known to have lower rates of heart disease and cancer, it hasn’t been clear whether ingesting high doses of those same nutrients in pill form results in a similar benefit.
NYBC BLOG: 1. In fact, most of the studies making news are surveys of people with no known vitamin deficiency and no evident health problem. The studies cited generally found that there was no improvement in rates of disease development over time (heart disease and cancers, primarily) for people taking the vitamins, as opposed to those who didn’t. On the other hand, NYBC’s interest has focused on the detection of vitamin deficiencies in people with chronic illnesses such as HIV, and then targeted supplementation and its results. For example, supplementation with Vitamin D (plus calcium) in people that are deficient has been found to have benefit, both for bone health and for reduction of cardiovascular disease risk (and, according to more recent research, for cancer risk as well). The same goes for supplementation with people deficient in minerals; in a well-known study, University of Miami researchers identified selenium deficiency in people with HIV, and also found that supplementing with this mineral improved health in this group. More generally, many vitamin and other nutrient deficiencies have been detected in people with HIV, and there have been many studies showing health benefits from supplementing to counteract these deficiencies. So, in conclusion, we are not terribly surprised if people with no known vitamin deficiencies and no known health problems are found not to gain much, if any, health benefit from taking vitamins–but that’s really a different question from those (many) studies showing that specific deficiencies and their related disease states can often be successfully addressed by supplementation.
2. Regarding vitamins and cancer: we certainly recommend caution here, and have frequently referred people to the Memorial-Sloan Kettering Cancer Center website on complementary medicine for guidance. Studies have indicated that vitamin supplementation (with C, for example) can accelerate certain cancers. However, as the MSKCC website shows, there is wide interest in, and much evidence for, use of certain dietary supplements as adjuncts in cancer therapy. The world of dietary supplements is much bigger than just the short list of vitamins; and research on supplements and cancer is a major topic among projects funded by such sources as the federal government’s National Center for Complementary and Alternative Medicine. Indeed cancer research has focused quite often on the therapeutic potential of botanical sources. The cancer drug paclitaxel, to give just one example, derives from the yew tree; and many traditional botanicals continue to be studied for their anti-cancer properties: turmeric/curcumin, green tea (with its polyphenols), silymarin, astragalus, to name just a few.
3. While the vitamin studies reported in the NYT article are negative, no one disputes the fact that nutrition has an enormous impact on health. In fact, the New York Times also recently ran articles reiterating the substantial health benefits of the “Mediterranean diet” (good fats like olive oil rather than bad fats; fish rather than meat; carbs from beans, peas, lentils; more veggies than meats), which has been associated with lower risk of heart disease and–in a newer area for research–a lower risk of depression and other mental health disorders. So, can the clear health benefits of a particular diet be translated in any useful way to the field of supplements? One obvious “yes” comes in the increased study and use of fish oil/omega-3 fatty acid supplements over the last few decades. Here’s a case in which an individual nutrient within a healthful diet has been isolated and can be usefully delivered as a supplement that bestows health benefits. (Fish oil supplements have a particular advantage over food sources, too: they can be refined to eliminate mercury contamination, a growing concern these days, whether you are eating fresh or canned fish.) We certainly know that it is possible to extract a component from food and use its particular properties to confer a health benefit, while leaving behind some other parts of the food that we don’t want or need. (This is the case with whey protein powders, which leave behind milk fat, but keep the whey protein with its interesting nutritional benefits.)There may also be increasing recognition that effective supplementation can require a wide-spectrum approach. Instead of emphasis on single vitamins, we’ve known for a while that the B vitamins work together and are usually best taken as a complex; or that a complex of carotenoids from vegetable sources is probably better than just a few select samples of these compounds. Of course, we would like to have more research about the particular value conferred by “food-based” supplements such as the popular “green foods.” In short: do choose a good diet to stay healthy, but don’t throw out the supplements, which can also make their contribution to your health and well-being!