A common question I get from people is, “Which vitamins and supplements should I be taking?” Zinc? Iron? Coenzyme Q10? Which nutritional supplements are proven to improve health and are recommended for healthy individuals? The truth is that the answer depends on who you ask. Different doctors, nutritionists, and expert organizations give different answers depending on their standards of proof and their personal or institutional biases. Indeed, I too have my own biases and standards.*
However, one nutritional supplement we nearly all agree on is folate supplementation in women of childbearing age — that is women who are planning to become pregnant or who could become pregnant. In fact just earlier this month, the U.S. Preventive Services Task Force, the gold standard in preventive medicine, reaffirmed their recommendation for daily folic acid supplementation. Specifically they state that “all women planning or capable of pregnancy take a daily supplement containing 400 to 800 micrograms of folic acid.”**
Folate (or vitamin B9) is a water-soluble vitamin that occurs naturally in foods, particularly leafy green vegetables like spinach and turnip greens, citrus fruits and bananas, avocados, and dried beans and peas. Folic acid is the synthetic or manmade form of folate that is found in supplements and added to fortified foods such as breads and cereals. Folate helps produce and maintain new cells, which is especially important during periods of rapid growth such as pregnancy and fetal development. However, despite its wide availability, only a third or so of reproductive age women are receiving sufficient amounts of folic acid.
The benefit of folic acid supplementation is that it reduces the risk of neural tube defects. Neural tube defects are a type of birth defect that result from a malformation of the unborn baby’s central nervous system. They are among the most common birth defects in the United States affecting 1 in every 1000 pregnancies. When started at least one month before conception and continued through the first trimester, folic acid supplementation has been shown to reduce the risk of neural tube defects.
The reason folic acid is recommended for all women of childbearing age is two-fold. One is that studies show that to be most effective folic acid supplementation must begin at least 1 month before conception. The central nervous system develops during the first month of pregnancy, before many women realize they are pregnant. Two is that about half of pregnancies in the United States are unplanned. As a result, all women who are capable of becoming pregnant — not just those who are planning on becoming pregnant — are advised to take folic acid.
Folic acid can be taken as an individual supplement or as part of a prenatal vitamin. While most of the other nutritional supplements found in prenatal vitamins have no proven benefit to mother or baby, they are generally considered safe when taken in the appropriate doses. Regardless of which formulation you choose, make sure it includes between 400 to 800 micrograms of folic acid and that you take it regularly.
While the experts argue about which other supplements are best for people like you, make sure you cover your basics and are at least taking the one supplement unquestionably proven to make a difference. If you are planning to become pregnant or could become pregnant take folic acid every day.
- Shantanu Nundy, M.D.
* Based on the best available evidence, the only nutritional supplement I recommend in healthy individuals is folate. While other vitamins may help protect against disease or are found to be lacking in many healthy individuals, folate is the only supplement shown to actually improve health. For example, studies consistently show that many people do not receive the daily recommended amounts of calcium and vitamin D in their diets. At the same time, studies show that calcium and vitamin D help protect against bone loss and osteoporosis. However, to date studies that have taken post-menopausal women and randomized them to receiving calcium and vitamin D or placebo have not shown any health benefit of supplementation. While these women did improve their calcium and vitamin D levels, their risk of fracture was unchanged. At the same time they had an increased risk of kidney stones, a painful condition that can lead to permanent kidney damage. Thus my bias is to wait for the data to definitively show a health benefit from supplementation and not simply rely on documentation of common deficiencies or in vitro benefits.
** This recommendation does not apply to women who have had a previous pregnancy affected by neural tube defects or women taking antiseizure medications, who are typically recommended to take higher doses of folic acid.