Beef - it may be what's for dinner, but according to Harvard University doctors, that steak or hamburger may mean a greater risk of breast cancer.
A new study by Harvard researchers suggests red meat consumption in women as early as their 20s may increase their risk for developing a certain type of breast cancer.
The researchers followed and surveyed more than 90,000 female nurses for 12 years, concluding that the more red meat women consumed during their 20s, 30s and 40s, the greater their risk was for developing hormone-receptor positive breast cancers.
The reason why red meat was strongly associated with breast cancer, however, is still unknown, said Eunyoung Cho, the lead author of the study, in a press release.
Hormone-receptor positive breast cancer occurs when levels of estrogen or progesterone stimulate tumor growth.
Women who eat more than 1 1/2 servings of red meat each day have nearly double the risk for hormone receptor-positive cancer compared with those who eat less than three servings per week, the study said.
One serving is the same as about one hamburger patty or hot dog.
While Harvard's findings may seem alarming, they don't provide an exact conclusion because the study was through surveys and not through scientifically controlled experiments, said Carol Johnston, chairwoman of ASU's Department of Nutrition.
The results are nevertheless "interesting" and need to be further investigated, Johnston added.
Johnston, who is a vegetarian, said the study does not mean women who like a good steak or hamburger need to cut red meat out of their diets altogether.
"It's not perhaps the meat itself," Johnston said. "It's the lifestyle that goes with that consumption."
People who eat excessive amounts of meat each day often get their food from fast food restaurants, have higher levels of stress, exercise less and may have unhealthy smoking or drinking habits, Johnston said.
Even if all those factors don't come into play, the methods for cooking red meat often cause problems, Johnston added.
Frying, burning or charring red meat changes the chemical composition, making it carcinogenic, meaning it can cause cancer, she said.
Plus, the problems with red meat extend beyond women's health issues, Johnston said.
Red meat is high in saturated fats, which can increase risk for heart disease, and processed red meats have been linked to prostate cancer.
The best course of action, Johnston said, is merely to live an active, healthy lifestyle, not smoke, learn how to control stress and eat moderately.
"The sooner you adopt a healthy lifestyle, the sooner the better off you're going to be," Johnston said.
Reach the reporter at: Annalyn.Censky@asu.edu.
