Researchers worldwide are working to discover other factors that affect Alzheimer risk. Some of the most exciting preliminary evidence suggests that strategies for general healthy aging may also help reduce the risk of developing Alzheimer’s. These measures include control-ling blood pressure, weight and cholesterol levels; exercising both body and mind; and staying socially active. How Alzheimer’s disease affects the brain Scientists believe that whatever triggers Alzheimer’s disease begins to damage the brain years before symptoms appear. When symptoms emerge, nerve cells that process, store and retrieve information have already begun to degenerate and die. Scientists regard two abnormal microscopic structures called “plaques” and “tangles” as the hallmarks of Alzheimer’s disease. Amyloid plaques (AM-uh-loyd plaks) are clumps of protein fragments that accumulate outside of the brain’s nerve cells. Tangles are twisted strands of another protein that form inside brain cells. Scientists have not yet determined the exact role that plaques and tangles may play.