What is the difference between Alzheimer’s and dementia?

Dr Rob Hicks, Spring Chicken GP says:

Dementia is a collection of symptoms that include memory loss and problems with thinking. There are a number of causes of dementia, of which Alzheimer’s disease is the most common.

Other causes of damage to the brain that result in dementia include a lack of oxygen to the brain as occurs during a stroke – called vascular dementia – and when abnormal structures called Lewy bodies develop inside brain cells resulting in the type of dementia called ‘dementia with Lewy bodies’.