The burden related to the ever-increasing dementia prevalence in older individuals, imposes the implementation of prevention strategies. It is now known that brain lesions related to Alzheimer's disease precede the onset of the first symptoms. Consequently, prevention strategies should be implemented early, before clinically overt dementia. Blood and spine fluid tests, electroencephalogram, brain magnetic resonance and brain nuclear imaging should help physicians to better target "high-risk" patients prone to benefit from such strategies, already in a preclinical disease stage. Since no efficient pharmacological treatments exist for the time being, lifestyle factors such as nutritionand physical exercise are the cornerstones for dementia prevention.