It starts with forgetfulness: Where did I leave my key? What's the name of that guy on TV again? Around eight percent of people over the age of 65 suffer from slow memory loss, and the trend is rising: the nerve cells die off and the exchange of information between the brain cells no longer works.

Suspected triggers: protein deposits in the brain, known as beta-amyloid plaques.

Cause unclear: The findings on these protein deposits are contradictory. Although they can be detected in all Alzheimer's patients, there are also many people who do not develop Alzheimer's despite considerable deposits.

Inflammation: Inflammation often occurs around the deposits. The body tries to defend itself against the protein - and damages the body's own tissue in the process. This inflammation could contribute to the development of Alzheimer's disease.

Treatment: The disease cannot be cured - but there are a number of medications that can delay its progression and thus improve quality of life. It is therefore important to see a doctor at the first sign of the disease.