High Fiber Diet Linked to Immunotheraphy Response

A high-fiber diet is associated with higher survival rates in patients with melanoma being treated with a type of immunotherapy called checkpoint inhibitors, according to study results published in Science. The high-fiber diet is similar to the one endorsed by the American Cancer Society, and recommends high consumption of fruits and vegetables, whole grains, and legumes – a regimen that’s also helpful for prevention of heart disease and promoting general good health, but unfortunately, only 1 in 10 Americans follow.

Diet is a key determinant of the health of the microbiome, and the gut microbes associated with response to immunotherapy are the same bacteria that help us digest fiber, so it makes sense that a high-fiber diet would be associated with a positive response. In this particular study, patients who reported higher consumption of dietary fiber intake from fruits, vegetables, legumes, and whole grains experienced significantly longer PFS (progression-free survival – length of time after treatment that the disease does not get worse). Every 5-gram increase in daily fiber intake correlated with an approximately 30% lower risk for cancer progression or death. Probiotic supplement use was not associated with a significant difference in PFS or response to immunotherapy, proving that food is really the best medicine.

Based on these and other similar studies that show improved outcomes to cancer therapy with a change in diet, oncologists should be recommending a plant-based, high-fiber diet to patients. And for those of us who are fortunate enough not to have cancer, this is also the best diet to prevent getting it.