A review of studies involving intake and cancer was published in Current Opinions in Obstetrics and Gynecology (2004; 16(1):19-25). The authors note that recent studies indicate that folate plays an important role in the prevention of breast cancer. Folic acid, or folate is a nutrient that is found in fresh produce (folate and foliage have the same root). The anti-cancer effect is especially true for women who consume alcohol. The authors note that some data also supports a role of vitamin D in the prevention of breast cancer, although that effect is minor.

Research in the June 12, 2006 online edition of the journal Cancer showed that folic acid supplementation may be beneficial against leukoplakia found on the larynx. Leukoplakia are pre-cancerous lesions. Folic acid is found in fresh produce; it is named from the same root as the word “foliage”. The Italian researchers found that when subjects took folic acid supplements, the leukoplakia did not turn cancerous, and in some instances, the lesions disappeared.

It was a small study, involving 43 subjects. The subjects with leukoplakia had lower levels of folate (a form of folic acid) in their blood. For six months the subjects took 5 mg of folic acid every eight hours. This is a high dose; the RDA for folic acid is 800 mcg (or 0.8 mg) per day.

Homocysteine is an amino acid that is linked to osteoporosis, cancer and heart disease. Folic acid is needed to convert it to the more useful amino acid, Taurine. During the study, the homocysteine levels in the subjects dropped. The researchers checked the leukoplakia every 30 days. None of the lesions turned to cancer while the subjects took the supplementation. In 28% of the subjects, the lesions disappeared. In another 44% of the subjects there was a reduction in the lesions.

Research appearing in the March 15, 2006 Journal of the National Cancer Institute shows that folic acid in the diet (from food sources—not supplements) may reduce the incidence of pancreatic cancer. In their report, the researchers cite earlier studies that folic acid protects against colorectal and breast cancers.