Two thirds of people over the age of 50 fear that they will develop the condition, while just one in 10 said they were frightened about getting cancer.
Just under four per cent said they were frightened about getting a heart condition and less than one per cent were concerned about developing diabetes, according to a survey of 500 adults aged over 50 from across the UK who were asked which condition they feared most.
There are around 800,000 people with dementia in the UK but as the population ages, this figure is expected to soar in coming years.