Choosing fish and nuts instead of pickles and ice cream may help prevent your daughters from developing breast cancer later in life. According to recent evidence, pregnant and nursing women who eat foods packed with omega-3 fatty acids may reduce breast cancer risk in their daughters.

“Diet matters, Mom,” says lead researcher W. Elaine Hardman, PhD. “Pregnant women need to eat more fish or take an omega-3 supplement to help reduce the risk of cancers in the next generations.”

A typical Western diet—which is deficient in omega-3s but heavy in omega-6 fatty acids found in meat, eggs, poultry, cereals, breads, baked goods, vegetable oils, and margarine—can increase maternal estrogen levels, which raise the risk of breast cancer in offspring, according to an animal-based study presented at the American Association for Cancer Research’s annual meeting.