Unlike refined (white) grains, whole grains retain the bran and germ—two key parts that contain nearly all the fiber and nutrients. Consuming whole grain foods instead of refined grains is linked to numerous health benefits, including reduced risk of heart disease, stroke, and type 2 diabetes. High-fiber whole grains can also help maintain a healthy weight by increasing satiety and delaying hunger.

On the other hand, a consistent intake of refined grains—such as white rice, white bread, and refined breakfast cereals—may worsen acne in some cases. Heavily processed grains are quickly broken down during digestion, leading to a rapid rise in blood sugar levels. In response, the pancreas produces a surge of insulin—the hormone responsible for moving glucose from the bloodstream into the cells. According to scientific hypotheses, high insulin levels enhance the binding of androgens (hormones involved in acne) to cells.

Make at least half your grain intake whole grains, such as oats, brown rice, quinoa, and barley. When shopping for bread or breakfast cereals, choose products made with 100% whole grains. If the label doesn’t say so, read the ingredient list. Look for whole grains—e.g., oats, whole wheat, whole rye, brown rice—listed first (ingredients are listed by weight, from highest to lowest). Choose products where all listed grains are whole.