Women who eat a lot of red meat early in life have a moderately higher risk of breast cancer, according to a new study, though experts not involved with the Harvard research are skeptical. The study tracked 89,000 women aged 24 to 43 and concluded that women who ate the most red meat had a 22% higher risk of developing the cancer, the BBC reports. "Replacing red meat with a combination of legumes, poultry, nuts, and fish may reduce the risk of breast cancer," they wrote, though other experts say that dozens of other studies have failed to establish any connection between breast cancer and diet.
"Diet is notoriously difficult to measure," a cancer expert at Oxford University tells the Guardian. "The most reliable measure of meat consumption is whether or not people are vegetarian. Vegetarians do not have lower risks of breast cancer than non-vegetarians, further supporting other evidence that meat consumption is unlikely to play a major role in breast cancer." The Harvard researchers, however, say most other studies have looked at diet in midlife or later, not in young adulthood—and an American Cancer Society expert tells the AP that the connection is plausible because "breasts are still developing and are more susceptible to carcinogens before women have their first full-term pregnancy."