People fear cancer more than any other disease.
A poll of more than 2,000 adults found 35pc fear cancer while 25pc are most worried about developing Alzheimer's disease.
Just 3pc are concerned about heart disease more than other illnesses, while 5pc are worried about stroke and 7pc think motor neurone disease is the worst type of disease to get.
Some 2pc of people surveyed for Cancer Research UK said they were worried about catching HIV.
Top of the list of cancers most feared is brain cancer (16pc), followed by bowel cancer (10pc).
People said they feared brain cancer because they thought it was the cancer they were most likely to die from (57pc) or had the worst symptoms (47pc).
Among men, bowel cancer is the second most concerning type (12pc), followed by lung (10pc) and prostate (10pc).
For women, breast cancer (13pc) caused the most concern after brain cancer, followed by bowel (8pc) and lung (7pc).
When asked about survival rates, 21pc of people surveyed thought breast cancer had the best survival rate while 12pc said testicular cancer.