Folic acid: the good, the bad and the ugly.

The author reflects on the advantages and the disadvantages of the integration of folic acid into the U.S. diet. He presents a background of the link between folate and cancer based on observations on the efficacy of folic acid antagonists in the treatment of animal and human leukemias. He describes the role of folate in methylation. The author also argues against adding more folic acid to the food supply.