Molecules: You'd better learn to live with them.
Folate is a cofactor, or a small molecule that is involved in the function of an enzyme. It's involved in a number of enzymatic reactions; perhaps the most important relate to the biosynthesis of DNA.
It's amazing to think about the fact that we've only known about its existence for seventy-odd years, considering its crucial role in metabolism. No doubt this was (partly) due to the fact that the requirement for folate is vanishingly small; it's on the order of half a milligram a day! Because of folate's central role in DNA synthesis (along with various other reactions, many of which are crucial to cell division); folate deficiency in pregnant women can be potentially dangerous. Any "prenatal vitamin" will contain folate because of this.
