As reported in a press release by Washington University in St. Louis, new research shows that girls between the ages of nine and 15 who consume peanut butter or nuts on a regular basis were 39 percent less likely to develop benign breast disease by the age of 30. Although noncancerous, benign breast disease increases the risk of cancer later in life.

According to Susan G. Komen, some of the most common benign breast diseases include hyperplasia, cysts, fibroadenomas, intraductal papillomas, sclerosing adenosis and radial scars.

“These findings suggest that peanut butter could help reduce the risk of breast cancer in women,” said senior author Graham Colditz, MD, DrPH, associate director for cancer prevention and control at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine.

Colditz is also the Niess-Gain Professor in Medicine at Washington University School of Medicine. He led the study with biostatistician Catherine Berky, MA, ScD from Harvard Medical School and Brigham and Women’s Hospital in Boston.

Research findings were based on the health histories of 9,039 girls enrolled in The Growing Up Today Study from 1996 to 2001. During 2005 to 2010, when the study participants were 18 to 30 years old, they reported whether or not they had been diagnosed with benign breast disease that had been confirmed by breast biopsy.

What researchers found was that the participants who ate peanut butter or nuts twice a week were 39 percent less likely than those who never ate them to develop benign breast disease. There was also evidence that beans, lentils, soybeans and corn might help prevent the illness as well. However, consumption of these foods was much lower in the girls so evidence was weaker.

Additionally researchers noted, “Girls with a family history of breast cancer had significantly lower risk if they consumed these foods or vegetable fat.”

Previous studies have linked peanut butter, nut and vegetable fat consumption to a lower risk of benign breast disease. However, participants of those studies were asked to recall their dietary intake during high school years after the fact. This recent study is the first to use reports from participants during adolescence with continued follow ups as cases of benign breast disease were diagnosed in the young women.

Due to the obesity epidemic, Colditz recommends that girls replace high calorie junk foods and sugary drinks with peanut butter or nuts.

This research was published in the journal Breast Cancer Research and Treatment.