If you have diabetes or prediabetes and you need motivation to get your blood sugar under control, consider this: a study published Dec. 2, 2014, in Annals of Internal Medicine suggests that diabetes in midlife appears to age the mind at a faster rate in later life. Researchers analyzed changes in the thinking skills of more than 15,000 people during a 20-year period. The average age at the start of the study was 57. Twenty years later, among people with a history of diabetes, there was 19% more decline than expected. There were even declines, although smaller, among people with a high blood sugar condition known as prediabetes. “We know that over time, diabetes, like hypertension, will cause mini-strokes in the brain that will impair one’s thinking and memory. This study strengthens the claim that addressing cardiovascular risk factors like diabetes early may prevent dementia in the future,” says Dr. David Hsu, a psychiatrist in the Center for Alzheimer Research and Treatment at Harvard-affiliated Brigham and Women’s Hospital. You can lower your blood sugar—and your risk of diabetes—by exercising, losing weight, and cutting back on refined grains and added sugars.