The maker of my multivitamin says it doesn't include folic acid because too much from supplements can be harmful. Is that true?
Although folic acid is an essential B vitamin with important functions, there are legitimate concerns about getting too much folic acid from supplements and fortified foods. For example, a high daily dose of folic acid from a supplement has been associated with a more than doubling of the risk of prostate cancer. High doses of folic acid from supplements can also complicate the diagnosis of vitamin B-12 deficiency and cause kidney damage. For details about how much is too much, and how this compares to the amounts of folic acid in the many popular multivitamins and B vitamins we've tested, see the Multivitamin Supplements Review and B Vitamin Supplements Review >>