Fortified foods: Too much of a good thing?

You say folic acid, I say folate
Folic acid is the synthetic form of the B vitamin folate, which is naturally found in foods such as dark leafy greens, citrus fruits, legumes and nuts, such as peanuts. In its natural form, folate can be lost through cooking and exposure to heat, while folic acid is the more stable form used for fortifying foods or in supplements.

Both forms seem to offer a defence against some cancers, including colon cancer and breast cancer, especially in women who consume alcohol. A shortfall of folate or folic acid is linked to a higher risk of colon cancer, but too much of the latter, the synthetic form, may also boost the risk. It's possible that large amounts of folic acid may be a growth factor in precancerous or cancerous cells. It's also possible that the excess may enhance the transformation of benign growths into cancers, or of small cancers into larger ones. Too much folic acid can also mask a deficiency of vitamin B12.

Folic acid will be on the ingredients list if the synthetic form is used to fortify foods. Note that the daily recommended intake of folic acid is 400 mcg (0.4 milligrams), the amount found in some multivitamins. The maximum safe amount from fortified foods and supplements is 1,000 mcg (1 milligram) per day.

Rosie Schwartz, RD, is a Toronto-based consulting dietitian.

This article was first printed in the October 2008 issue of Homemakers Magazine. Click to subscribe online and never miss an issue.