The over-50s are increasingly putting themselves at risk of sexually transmitted infections because they are not using condoms, research suggests.
Condoms protect against infection - no matter what age you are
More than one in 10 of those surveyed admitted not using a condom to prevent an infection - despite not knowing their partner's sexual history.
Sexually transmitted infections (STIs) are becoming more common for all ages - including the over-50s. Saga Magazine questioned nearly 8,000 people aged 50 and over.
The survey examined the general health of this group, as well as their sex lives.
Emma Soames, Editor of Saga Magazine, said, "There is a wide perception that STIs are an issue for the young, and also because over-50s don't need contraception to prevent pregnancy, they feel it is fine to have unprotected sex."
The Health Protection Agency confirmed there had been a rise in STI diagnoses in all age groups.
Gwenda Hughes, Head of the STI section at the HPA Centre for Infections, said: "It may be that older people are less aware they are at risk of STIs.
"If you are having sex with a new partner and don't use a condom you can catch an STI, no matter what your age.
"If people have put themselves at risk they should get tested, even if they don't have symptoms."
The Saga magazine study also found 65% of respondents were sexually active and nearly half had sex at least once a week.
"Its great people are going on having sex and there is no doubt Viagra has a role to play," said Miss Soames.
"Sexual performance enhancing drugs are now part of the landscape and prolong the active sex lives of many couples."
The survey also suggested the quality of sex was better for many over the age of 50.
As many as 85% of respondents said they felt sex was less pressurised after the age of 50, and 70% found it more fulfilling than when they were younger.
This could be because people tend to have less stress at that stage in their life, and are more likely to feel comfortable with their bodies, Saga said.
The respondents do, however, have less sex than in their younger years, with 84% having sex less often in their 50s than in their 20s or 30s.
"But it's a case of never mind the quantity - they are enjoying the quality," Ms Soames said.
Respondents were largely from the top two socio-economic groups, and 75% were married.
Three-quarters said they tried to eat the recommended five portions of fruit or vegetables a day.
The survey also found that the older respondents. were, the more likely they were to exercise. It found that 38% of those aged 65 and older exercise every day, compared to just 29% of 50 to 54-year-olds.