Folate, Alcohol, and Cancer Risk
The associations between alcohol intake and certain cancers are well known, but complex. A recent review addressed the relationships between cancer risk, folate and other methyl-related nutrients (i.e., methionine, vitamin B6, and vitamin B12), alcohol, and a specific genetic polymorphism that affects folate metabolism (MTHFR 677C->T). The review found that
- women who drink alcohol and have a high folate intake are not at increased risk of breast cancer;
- diets low in methionine and folate but high in alcohol are associated with a higher risk of colorectal adenoma and cancer;
- people with the MTHFR 677C->T polymorphism who have adequate folate intake may have a lower risk of colorectal cancer but are especially sensitive to alcohol’s carcinogenic effects.
The author summarizes intake recommendations based on these conclusions, such as increasing intake of foods rich in folate (e.g., citrus fruits and juices, dark green leafy vegetables, dried beans and peas) and methionine (e.g., poultry, fish, low-fat dairy), and/or using folate supplements.
This exhaustive review of a complex area suggests that folate may reduce the risk of breast and colorectal cancer in people who drink alcohol. Fortification of foods has led to a decrease in the prevalence of inadequate folate intake. Still, for those who consume alcohol and have a diet low in methyl-related nutrients, it is reasonable to advise folate supplementation or increased consumption of foods rich in folate, methionine, vitamin B6, and vitamin B12. Because of possible folate toxicity, clinicians should recommend increased folate intake only to people with inadequate intake and, in particular, to those who also drink alcohol.R. Curtis Ellison, MD
Bailey LB. Folate,
methyl-related nutrients, alcohol, and the MTHFR 677C->T polymorphism
affect cancer risk: intake recommendations. J Nutr. 2003;133:3748S–3753S.