Progress in research methodology allows for better characterizing biological processes of brain aging, and therefore to detect dementia or Alzheimer's disease (AD) at a very early stage. Clinically, AD is characterized by progressive memory loss. Moreover, psychiatric symptoms such as anxiety, apathy or depression are frequently present, and may overlay cognitive dysfunction in early AD. There is a broad consensus in the research community that early stages of AD offer a promising window of opportunity for potential therapeutic intervention. Recent studies also suggest that a healthy and active lifestyle has a significant preventive effect. By supporting the patient in lifestyle and health management, the treating physician can make a relevant contribution to the prevention of AD.