Depression and obesity also promote later illness. Over 1.8 million people in Germany suffer from the previously incurable Alzheimer's disease, which causes the nerve cells in the brains of those affected to steadily deteriorate.

Regular physical activity and exercise can slow the progression of dementia and Alzheimer's. Untreated high blood pressure can lead to vascular changes and increase the risk of vascular dementia. An online dementia test with pictures, numbers and shapes can reveal the first signs. Am I becoming demented? Ten risk factors that promote illness.