Pregnancy and "Folic Acid Follies"

Slate Magazine: Folic Acid Follies, by Amanda Schaffer:

Pregnant women should stop popping these pills like candy.

No woman who's expecting, or expecting to expect, can avoid the advice, from any doctor or health site worth its salt: Take folic acid. The vitamin deserves its exalted status. When women take it before and during pregnancy, it reduces the risk of devastating neural-tube defects in the fetus. It's one of the only things we can do to improve fetal health that is supported by rigorous evidence.

But these days millions of women (and men) are getting high doses of the vitamin—and not because we're piling our plates with natural sources like spinach and collard greens. Since the late 1990s, the United States has fortified many breads, cereals, and pastas with folic acid. And then there are the supplements: both in regular multivitamins and freestanding folic acid pills. . . .