Several studies over the years have shown that high fiber intake is associated with a reduced risk of certain diseases and cancers, possibly due to a healthy microbiome. Whether a high-fiber diet may have beneficial effects on breast cancer risk has been debated, but new analysis of existing studies has found a positive link between the two.
Past studies have linked high-fiber foods to reducing the risk of cardiovascular disease, colon cancer and obesity. The reason is thought to be that fiber plays an important role in helping to maintain healthy gut bacteria, which may play an important role in both physical and mental health. Fiber can be found in some plant-based products, including whole wheat and corn, bananas, carrots, sweet potatoes and other foods.
Harvard T. Researchers at H. Chan Public Health recently published a new analysis evaluating 20 different observational studies. Based on the data, the analysis found that people who ate the highest levels of fiber had a significantly lower risk of breast cancer — up to 8 percent at the highest level.
The study found that, based on available data, total fiber intake (including soluble and insoluble fiber) was associated with a reduced risk of breast cancer in premenopausal and postmenopausal women. Similarly, soluble fiber is particularly associated with reduced breast cancer risk.
Soluble fiber refers to the type of fiber found in barley, peas, lentils, seeds, certain vegetables and fruits, oat bran and other foods. Insoluble fiber includes the skins of certain fruits and seeds, brown rice and whole grains. The researchers note that these findings do not suggest that fiber itself is a direct cause of reduced breast cancer risk — rather, it suggests that certain lifestyle factors, such as a healthy diet, may affect a person’s risk of developing the deadly disease.