Some months ago, results of a Swedish study published in one of the premier scientific journals in the field, The American Journal of Clinical Nutrition, revealed a startling association. After following over 35,000 women for 9 1/2 years, they noted that those who reported taking a multivitamin everyday had a 19% greater likelihood of developing breast cancer. This was an unexpected finding, contrary to the protective association seen with increased intake of fruits, vegetables and whole grains and lower rates of many cancers. In trying to explain the results, they postulated it might be the folic acid in the pills that was accountable.
You see, folate is an extremely important B-vitamin, crucial for proper DNA replication. Lack of folate has been shown to result in increased birth defects, especially neural tube defects like spina bifida, which occur during the first few weeks of the embryo’s life. That’s one main reason the government started fortifying grains with folic acid. It’s easy to get enough folate from your food if you eat enough vegetables regularly, but many young women of childbearing age do not have healthy enough diets. At the same time, while over one-third of the adult population of America is clinically obese, ironically many of these individuals are actually under-nourished. They get more than enough calories, but not enough vitamins, minerals and antioxidants.
The problem with multivitamins is that the artificial form of folate that is added to most pills, folic acid, enters the cell and interacts with another vital nutrient, vitamin B12, slightly differently. It’s actually much more bioavailable than the natural form, so that you get a big hit from the pill. But that may not be completely beneficial.
A subsequent meta-analysis, which is a grouping of lots of smaller studies so the results can be considered as if it were a really, really large study, did not find the same association between multivitamins and breast cancer. They found no statistical significance one way or another. However, given the gravity of the subject, they recommended further research be done on the subject.
My approach to nutrition is to encourage eating more delicious and colorful vegetables and fruits everyday, as well as a balance of other food groups, so that you maximize your nutrition in the most natural as well as most pleasurable way possible. Almost everyone thinks she or he is eating healthy. A registered dietitian or licensed nutritionist can measure your actual nutrient intake scientifically with enough accuracy to determine your individual needs and how well you are meeting them, which can be surprising. For my clients who do require supplements, especially those over 40, I recommend locating a brand of multivitamin that contains a natural form of folate and taking the pill 3 or 4 times a week. With nutrition, as with many other things in life, too much of a good thing is not always helpful.