High-Fat Diets Linked with Breast Cancer

Diets high in saturated fat may increase the chance of developing 3 common types of breast cancer, a new study says. The study included more than 337,000 women who answered questions about diet. In the next 11½ years, about 10,000 were diagnosed with breast cancer. Researchers adjusted the numbers to account for other things that can affect breast cancer risk. They found that women whose diets were high in total fat and saturated fat were 30% more likely to develop 2 specific types of breast cancer than women who ate the least fat. These cancers are known as estrogen-receptor (ER) positive and progesterone-receptor (PR) positive. They grow in response to hormones. Women who ate the most saturated fat were also more likely to develop HER2-negative breast cancer. These cancers do not contain the HER2 protein, which promotes cancer growth.