High Folate Intake May Reduce Risk of Colorectal Cancer - updated 7/7/11

http://www.sciencedaily.com/releases/2011/07/110705123616.htm

ScienceDaily (July 5, 2011) — Intake of high levels of folate may reduce colorectal cancer risk, according to a new study in Gastroenterology, the official journal of the American Gastroenterological Association (AGA) Institute. Folate is a water-soluble B vitamin that occurs naturally in food.

"We found that all forms and sources of folate were associated with lower risk of colorectal cancer," said Victoria Stevens, PhD, of the American Cancer Society and lead author of this study. "The strongest association was with total folate, which suggests that total folate intake is the best measure to define exposure to this nutrient because it encompasses all forms and sources." Total folate includes naturally occurring food folate and folic acid from fortified foods and dietary supplements.

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The study also addressed concerns that the intake of high levels of folate frequently consumed in the U.S. -- as a result of the recent increase in the use of folate-containing supplements and mandatory folate fortification of food -- may actually increase risk of cancer. No increased risk of colorectal cancer was found for the highest intake levels, suggesting that the high levels of this vitamin consumed by significant numbers of Americans should not lead to increased incidence rates of this cancer in the population.


http://ods.od.nih.gov/factsheets/folate/

Leafy green vegetables (like spinach and turnip greens), fruits (like citrus fruits and juices), and dried beans and peas are all natural sources of folate [5].

In 1996, the Food and Drug Administration (FDA) published regulations requiring the addition of folic acid to enriched breads, cereals, flours, corn meals, pastas, rice, and other grain products [6-9]. Since cereals and grains are widely consumed in the U.S., these products have become a very important contributor of folic acid to the American diet. The following table suggests a variety of dietary sources of folate.

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