Around one in five young Britons has sex with a new partner while overseas, finds research published ahead of print in the journal Sexually Transmitted Infections.
And they are apparently opting for British or European sexual partners in the belief that this minimises the chances of HIV infection, but seemingly unawares of their risks of contracting other sexually transmitted infections.
The findings are based on interviews with a random sample of 12,000 men and women aged between 16 and 44, who took part in the 2000 National Survey of Sexual Attitudes and Lifestyles (NATSAL).
Just under 14% of men, and just over 7% of women, said they had sex with someone new while overseas, with this type of liaison accounting for one in 10 of all men's partnerships and one in 20 of women's in the past five years.
The young and single were the most likely to have sex with someone new while overseas.
Almost one in four men (23%) and one in six women (17%) between the ages of 16 and 24 said they had done this.
Half of all respondents said their overseas partners were British, and more than one in three said these were from another European country.
This is likely to reflect choice of destination as three quarters of overseas trips in 2005 were to European countries, but it may also indicate perceived risk, say the authors.
When quizzed about potential HIV risk, respondents cited North America, Thailand, and Kenya as high risk, and as higher than Britain.
Yet one in 10 men and one in 12 women who said they had had sex while overseas assessed their HIV risk as high or moderately high
Men were significantly more likely to have sex with Asian and North American partners.
Frequent sexual partners at home in the preceding few years and reporting sexually transmitted infections and HIV testing were associated with a greater likelihood of sexual activity while abroad, the responses showed.
This may indicate a pattern of risky sexual behaviour, say the authors, which is currently not being targeted.
Overseas travel has soared in the past five years, say the authors. Over 66 million trips abroad were made by UK residents in 2005, three times the number since the mid 1990s.
They suggest that healthcare professionals in GP surgeries, travel, and sexual health clinics need to do more to promote the safer sex message for people intending to go abroad