Being overweight increases the risk of cancer
People aged over 55 are less aware than younger adults of how to reduce their risk of cancer, a UK survey suggests.
A survey of 2,000 people found those in that age group were less likely to know that poor diet, being overweight and drinking alcohol all increase risk.
The World Cancer Research Fund said it is estimated healthier lifestyles could prevent a third of common cancers.
Cancer Research UK said the survey results were worrying given the disease is primarily one of old age.
The YouGov survey of almost 2,000 people found that 56% of the over-55s were aware a poor diet increases the risk of cancer, compared with 60% of younger adults.
Some 54% of the older age group knew that being overweight is another risk factor, compared with 59% of the under-55s.
A lower proportion of the over-55s than younger adults pointed to being physically active and limiting alcohol intake as ways to reduce cancer risk.
However, the survey did show that awareness overall of cancer risks had increased in the past couple of years.
The World Cancer Research Fund, which commissioned the survey, said there was convincing scientific evidence that all the lifestyle factors featured in the survey were associated with the risk of cancer.
Lisa Cooney, WCRF head of education, said: "The scientific evidence that we can reduce our cancer risk by making healthy lifestyle choices is overwhelming, so it is a real concern that so many older people are not aware of this.
"This is because if people do not know what increases and reduces risk then they are not in a position to make informed choices about their lifestyle.
"We need to get the message across that it is never too late to start thinking about cancer prevention."
She added there was still a long way to go in raising public awareness of the health issues to the levels seen with smoking.
Jessica Harris, health information officer at Cancer Research UK, said: "Living a healthy life can have a real impact on cancer risk, so we want everyone to know about the positive steps they can take to reduce their risk of cancer.
"It's worrying to see that awareness of these risks is lower among older people, especially since three-quarters of cancers are in people aged 60 or over."