According to the University of Maryland College of Agriculture & Natural Resources, folate, also known as folic acid, may reduce the risk of colorectal cancer, pancreatic cancer and breast cancer. In one study involving more than 25,000 adults, those who ate diets high in folate had fewer precancerous polyps, which are associated with the eventual development of colorectal cancer. Folate is found in dark green leafy vegetables, legumes, citrus fruits, citrus juices, fortified breakfast cereals and grain products. The highest concentration of folate is found in black-eyed peas, spinach, great northern beans, asparagus and broccoli. Research found folic acid in supplements is better absorbed by the body than the folate naturally occurring in foods. Folate is a water-soluble B vitamin that occurs naturally in food. Folic acid is the synthetic form of folate that is found in supplements. Folate, or folic acid, helps prevent changes to DNA that may lead to cancer.

From 1980 to 1994, the Nurses Health Study tracked over 88,000 women who were cancer-free at the beginning of the study. Researchers found that women ages 55 to 69 years in this study, who took multivitamins containing folic acid for more than 15 years, had a markedly lower risk of developing colon cancer.