from Brain Fitness 101: Answers to Your Top 25 Questions. Does a brain fitness program prevent Alzheimer's disease and other forms of dementia? Studies have shown mentally active people have lower rates and later onset of symptoms for Alzheimer’s disease and other forms of dementia. These diseases involve a number of variables like family history, physical fitness, nutrition, and brain fitness. People who remain intellectually active and engage in hobbies reduce the risk of Alzheimer’s disease by one third.