Scientists report that high doses of the supplement may be no better for the body than the daily recommended dose.
The mantra “the more, the better” doesn’t always apply for folic acid, a new study finds. A key liver enzyme converts folic acid to a useful form much more slowly in humans than it does in rats, researchers report online August 24 in the Proceedings of the National Academy of Sciences. The slow rate suggests that higher doses of folic acid may not be any better for the body than the daily recommended dose.
Chemists created folic acid in 1945 as a nutritional supplement because people weren’t getting enough folate, the natural form of the supplement, in their diets. Among pregnant women, this deficiency is strongly associated with birth defects such as spina bifida.
Folates help the body use the fuel it ingests, explains study coauthor Steven Bailey of the University of South Alabama in Mobile. To do the job of its natural counterpart, folic acid must first be activated by a liver enzyme called dihydrofolate reductase, or DHFR. But t