Smoking and cancer

Folates may play role in oral cancer

Folates—those B-vitamin nutrients found in oranges, legumes and leafy green vegetables—and select antioxidants are involved in complex relationships with oral cancer and smoking, according to research done at Tufts.


Folate levels are different in smokers and non-smokers, according to Dr. Joel B. Mason, director of the Vitamins and Carcinogenesis Program at the Jean Mayer USDA Human Nutrition Research Center on Aging.

Mason analyzed the diets and studied blood and cheek cells of 56 men and women between the ages of 30 and 80. Approximately half of the subjects had smoked at least 10 cigarettes a day for at least the past year. “Regardless of dietary intake, smokers had lower levels of folate in both blood and cheek cells, compared with non-smokers,” Mason reports. Consistent with previous research findings, the cheek cells of smokers had significantly more genetic aberrations—called micronuclei—which increase the risk of developing oral cancer, diagnosed in more than 300,000 people worldwide every year.

However, the research, published in the American Journal of Clinical Nutrition, did not prove a causal link. “Based on our findings,” Mason said, “it does not appear that folate depletion induced by smoking is a major avenue for the formation of the genetic aberrations that increase risk of oral cancer.”

It’s possible, he noted, that diminishing folate in cells may cause the cellular milieu to change, inducing the formation of cancerous cells.

Folate not only helps create and preserve cells, it is also critical for the synthesis of DNA—a universal set of blueprints for cells that, if sufficiently altered, often leads to cancer.