Folic acid fortification and supplementation questioned
A woman who becomes pregnant is prescribed by her obstetrician prenatal vitamin supplements. And one of the most important of these is folic acid. Folic acid is a synthetic form of folate; folate is an essential B vitamin that plays an important role in many bodily functions. Folic acid supplementation has helped prevent many birth defects over the years, especially spina bifida. What many of us may not know is that flour and grains in most developed countries, including the US, are also fortified with folic acid for more than a decade now.
Unfortunately, recent research studies are casting doubt on the benefit of folic acid fortification and supplementation. Several clinical trials have shown for example that folic acid does not reduce risks of developing chronic diseases and may even have some adverse effects. Below I summarize some of the studies on folic acid supplementation.
Folic acid and its effects on the genes of offspring
Researchers from the University of Toronto have observed in mice that folic acid supplementation during pregnancy induces changes in the genes of the offsprings. The changes may consist of either silencing or activating genes that suppress tumors. This suggests that maternal supplementation with folic acid can have an effect on the susceptibility of the offsprings to cancer.
Folic acid and heart disease
This clinical trial of Harvard’s Brigham and Women’s Hospital in Boston followed up 5,400 female health professionals for about 7.3 years. The results suggest that folic acid did not lower levels of the amino acid homocysteine, believed to be a biomarker for cardiovascular disease. Thus, folic acid supplemention does not reduce cardiovascular risks.
Folic acid and cancer
This study by researchers at Harvard Medical School looked at the effect of folic acid, vitamin B6, and vitamin B12 in reducing cancer risk in women. The results showed that a combination of these three vitamins did not protect women from breast cancer or total invasive cancer.
This recent research results raise the question of the benefits of folic acid fortification of food for the general population. Could it be that people in developed countries like the US are consuming too much folic acid? Could it be that long-term consumption of folic acid (as found in our food) can increase development of cancer in some people? Could folic acid supplementation during pregnancy increase cancer risk in the unborn child?
Currently, there isn’t enough evidence to change the clinical practice of taking folic acid supplementation during pregnancy. Several studies are ongoing to try to answer the aforementioned questions.