By Maureen Williams, ND
Healthnotes Newswire (May 18, 2006)—New research suggests that women who do not get enough folic acid should avoid alcohol, as that combination puts them more at risk for breast cancer.
Breast cancer continues to be the most common cancer in women. Diet has been shown to affect a woman’s risk of developing breast cancer. For example, fiber from whole grains, fruits, and vegetables, and omega-3 fats from fish have been found to decrease risk, while saturated fat and alcohol increase risk.
In the case of alcohol, some research has suggested that it changes the way the body handles estrogens—particularly synthetic estrogens used in hormone therapy—increasing estrogen’s cancer-causing effects. Other research has suggested that alcohol robs the body of folic acid (a B vitamin that is sometimes referred to as folate) and leaves it more susceptible to cancer.
The new report, published in the European Journal of Clinical Nutrition, was drawn from a large study known as “Diet, Cancer, and Health.” In the substudy, 24,697 cancer-free, postmenopausal women between ages 50 and 64 filled out a detailed questionnaire and then were followed for three to seven years, depending on when they entered the study.
The researchers measured women’s alcohol and folic acid intake and compared the results of those who developed breast cancer with those who did not. Higher alcohol was only associated with increased breast cancer risk in the women who got less than 300 mcg of folic acid per day. For these women, drinking on average 10 grams of alcohol (the amount found in slightly more than one glass of wine) per day increased their risk of breast cancer by 19%.
The recommended daily intake of folic acid for adults is 400 mcg. In the current study, alcohol’s negative effect on breast cancer risk was seen in women who were getting 75% of this amount. The researchers noted that “only a modest reduction in folate status appears to be necessary for the enhancement of carcinogenesis in association with alcohol intake.”
Good sources of folic acid include leafy green vegetables, legumes (such as beans), nuts, and whole grains, but folic acid can be destroyed by many kinds of processing, including cooking. Eating raw salads made from dark greens is a good way to add folic acid to the diet, and most multivitamins contain the full recommended daily amount.
The current findings add weight to existing research, including three previous studies that found a link between folic acid, alcohol, and breast cancer risk. “Women can be encouraged to take an active role in preventing breast cancer by eating a high-fiber, low-saturated-fat diet, exercising regularly, and getting adequate folic acid from food and supplements, especially if they drink alcohol,” says Alan Gaby, MD, chief science editor at Healthnotes.
(Eur J Clin Nutr 2006;60:280–6)
Maureen Williams, ND, received her bachelor’s degree from the University of Pennsylvania and her Doctorate of Naturopathic Medicine from Bastyr University in Seattle, WA. She has a private practice in Quechee, VT, and does extensive work with traditional herbal medicine in Guatemala and Honduras. Dr. Williams is a regular contributor to Healthnotes Newswire.