A new study has just discovered that there’s actually one simple thing that girls and young women can do to greatly cut their risk of breast cancer later in life.

A large U.S. study involving 44,000 women just released recommends that women get more fiber in their diet, according to a Reuters report.

The study, led by Maryam Farvid of the Harvard T.H. Chan School of Public Health in Boston and published in the journal Pediatrics, found that there’s a link between more consumption of dietary fiber and lower breast cancer risk. The researchers think that fiber may be causing breasts to develop in such a way that the long-term breast cancer risk is lowered, and it’s the first time scientists have followed such a large group for such a long period. Specifically, it’s possible the foods rich in fiber can reduce the risk of breast cancer by lowering estrogen levels, which has already been died to the development of breast cancer.

It’s possible that foods that are high in fiber are also high in other nutrients that play a role in reducing the risk of breast cancer, but the study took great pains to factor for other possibilities, and the connection with fiber was still strong.

“Previous studies of fiber intake and breast cancer have almost all been non-significant, and none of them examined diet during adolescence or early adulthood, a period when breast cancer risk factors appear to be particularly important,” Farvid said in a statement. “This work on the role of nutrition in early life and breast cancer incidence suggests one of the very few potentially modifiable risk factors for premenopausal breast cancer.”