By: Micheal Greger, MD, Director of Public Health and Animal Agriculture at the Humane Society of the United States.
That Black Women’s Health Study, which highlighted collards and carrots, was out of Boston University. Across the Charles River, the Harvard Nurse’s Health Study also tried to determine which plants were particularly protective in reducing breast cancer risk, and they identified nuts.
The intake of fiber and nuts during adolescence and incidence of proliferative benign breast disease, such as fibrocystic breast disease, fibroadenomas—noncancerous breast lumps—but is considered a marker for increased breast cancer risk. Depending on what biopsies show it could indicate anywhere from 30% to 1300% greater risk of going on to develop cancer.
Breast cancer can take decades to develop, so they wanted to start early, asking women what their diets were like in high school. Now in adults it’s clear, as you can see in this 2012 review, the more fiber you get in your diet the lower your risk of breast cancer… And same thing, apparently, when you’re younger. Women who had the most fiber intake during adolescence have a 25% lower risk of this potentially precancerous breast disease. But there’s fiber in fruits, vegetables, beans, whole grains, nuts, seeds—all whole plant foods.
Did any class of plant foods stick out? Nuts was found to be particularly protective. Two servings a week was associated with a 36% lower risk, but that raises the question, which type of nuts? Like peanut butter and jelly sandwiches or do you have to eat true nuts, like almonds, pecans, walnuts, that sort of thing. Just tree nuts, or peanuts as well? And the answer is both. Compared to those who rarely ate nuts, those eating just one or two handfuls a week during high school appeared to drop risk around 30%,
“In summary, their study observed significant inverse associations between adolescent dietary intake of fiber and nuts and risk of proliferative benign breast disease. Our results provide supportive evidence of the important role of dietary exposures during a unique period in a woman’s life in the earlier stage of breast carcinogenesis, the early stage of breast cancer development. These findings, if corroborated, may suggest a viable means for breast cancer prevention.”
Harvard also found that fiber and nut consumption was associated with a significantly longer lifespan in women. See What Women Should Eat to Live Longer. Soy consumption during adolescence also seems particularly protective. See Thursday’s video Why Do Asian Women Have Less Breast Cancer?. The reference to the Black Women’s Health Study was referring to Friday’s video-of-the-day Preventing Breast Cancer By Any Greens Necessary. What effect might even just a few weeks on a diet full of plants have on breast cancer cell growth? See Answer to the Pritikin Puzzle. Don’t nuts make you fat, though? You’d be surprised—see Nuts and Obesity: The Weight of Evidence.
About Michael Greger M.D.Michael Greger, M.D., is a physician, author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous “meat defamation” trial. Currently Dr. Greger proudly serves as the Director of Public Health and Animal Agriculture at the Humane Society of the United States.
Photo Source: NutritionFacts.org