Regular consumption in childhood tied to 39 percent lower odds of benign breast disease by age 30 .
Benign breast disease -- noncancerous changes in the breast tissue -- is a risk factor for breast cancer, experts agree.
The researchers followed more than 9,000 females, beginning when they were aged 9 to 15 in 1996, until 2010, when they were young women. Eating peanut butter three days a week reduced the risk of developing benign breast disease by 39 percent, said Dr. Graham Colditz, senior study author.
"I think this gives us enormous hope there are strategies we could be following to help prevent breast cancer that we haven't capitalized on yet," said Colditz, the associate director for cancer prevention and control at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine, in St. Louis.
The study, published online Sept. 17 in Breast Cancer Research and Treatment, was funded by the Breast Cancer Research Foundation and the U.S. National Institutes of Health.
Benign breast disease is fairly common, and a known risk factor for breast cancer, Colditz said. Before menopause, "about one in four women have a benign lesion, confirmed by biopsy," he said. "It's very clear there is a strong link between the benign lesion and the subsequent risk of invasive breast cancer."
Depending on the characteristics of the benign lesion, he said, benign breast disease could increase breast cancer risk by threefold.
The study participants were part of a long-term, ongoing study on the health effects of diet and exercise in young people. They filled out questionnaires about their diet annually from 1996 until 2001, then four more times until 2010. They also reported if they had been diagnosed with benign breast disease. In all, 112 women said they had.
The researchers looked at foods with vegetable protein and vegetable fats, then focused on individual foods, including peanut butter, peanuts or other nuts, beans and corn.
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