Fiber-rich whole grains are associated with many positive benefits in the body. There has been some research out of Columbia University Medical Center that suggests a high-fiber diet lowers your risk of cognitive impairment and Alzheimer’s disease as you age. It also reduces overall inflammation and oxidative stress, as well as potentially lowers blood pressure. All of these effects have a role in reducing the risk of brain disorders. It is key that you choose whole grains, however, not refined. White flour, for example, has an extremely high glycemic index and is associated with an increased risk of cancer.