After comparing fiber consumption and types of fiber intake with breast cancer incidence rates from 17 cohort trials, 2 nested case control trials, and 1 clinical trial, those who consumed the most fiber were found to have an 8% reduced risk for premenopasual and postmenopausal cancers compared to those who consumed the least amount.
According to the researchers the strongest associations with the reduced risk were seen in soluble fiber from cereals, fruits, legumes, and vegetables with the strongest associations being observed in fruit fiber.
The authors concluded that: “A random-effects meta-analysis of prospective observational studies demonstrated that high total fiber consumption was associated with a reduced risk of breast cancer. This finding was consistent for soluble fiber as well as for women with premenopausal and postmenopausal breast cancer.”
There are several possible mechanisms behind the reduced risk of breast cancer including improved blood glucose control and insulin sensitivity; increased levels of sex hormone binding globulin; and improved composition of intestinal microbiota.
High fiber diets were noted to be associated with increased intake of vitamins, minerals, phytochemicals, and other various compounds that offer protective effects that fight against cancer. Their findings also support the American Cancer Society’s recommended dietary guideline suggesting to consume fruits, vegetables, whole grain, and other higher fiber food choices to help reduce the risk for cancers.
