More on Vitamins and Pregnancy

One of the hardest parts about writing health stories is figuring out what to leave out. Last Friday I wrote a post that focused on prenatal vitamins and the risk of pediatric cancer. Although the vitamins reduced the risk of some cancers by 50 percent, I calculated that that was not a huge change because the absolute risk of getting cancer in childhood is so low.

"But isn't taking vitamins during pregnancy a good thing?" a reader asked. Yes, absolutely. Taking folic acid, for example, which is found in prenatal vitamins and fortified bread and other cereals, has dramatically reduced the numbers of neural tube defects in newborn babies.

I should have acknowledged that fact in the last paragraph of Friday's post. My oversight serves as a reminder that whenever you read or hear health news, you should ask yourself what has been left out. Even the best health writers can't cover everything.