London - Playing the field and racking up sexual conquests can almost double the risk of developing cancer later in life, research suggests.
A study of nearly 6 000 people found those who were the most promiscuous – and especially women – faced serious health consequences as they got older.
Researchers from Anglia Ruskin University in Cambridge discovered that women who had ten or more lovers through their lifetime were 91 percent more likely to develop cancer than those who had just one or remained celibate.
For men who had ten or more lovers, the risk rose 69 percent.
The researchers believe the link between sexual experience and cancer is caused by sexually transmitted infections (STIs), and that this is particularly the case for women because the sexually transmitted HPV virus is so closely linked to cervical cancer.
However, they also said that men and women who sleep around are more likely to smoke and drink alcohol, which are themselves linked to cancer.
"It is possible that the number of sexual partners one has had captures a combination of likelihood of exposure to STIs and lifestyle profile," their report stated.
The researchers, whose results were published in the BMJ Sexual & Reproductive Health journal, questioned 2 537 men and 3 185 women living in England. The participants, who were all over 50 but with an average age of 64, were asked how many sexual partners they had had, along with questions about their health.
The researchers found the risk of cancer increased depending on how many lovers someone had during their lifetime.
While the greatest risk was for those who had had ten or more, women who reported having had at least five were 64 percent more likely to have another serious health condition – although no such link was found for men.
Almost three-quarters of the participants were married.
About 29 percent of men and 41 percent of women said they had had zero or just one sexual partner. Another 29 percent of men and 35 percent of women had experience of two to four lovers; 20 percent of men and 16 percent of women reported five to nine partners; while 22 percent of men and eight percent of women said they had ten or more.
The researchers’ report added: "STIs can have long-term consequences for health, including greater risk of specific cancers.
"Rates of human papillomavirus (HPV) infection in sexually active young females have been consistently reported to range from 19 percent to 46 percent. Nearly all cases of cervical cancer can be attributable to HPV infection.
"Moreover, HPV has been found to be associated with cancers of the mouth, penis and anus – cancers that are most common in older adults. Other STIs, such as gonorrhoea infection, have been shown to increase the risk of prostate cancer in black men.
"The average age for men to be diagnosed with prostate cancer is between 55 and 69 years. Therefore, STIs may have a long lasting negative impact on adults later in life."
They suggested that cancer screening programmes should ask people about the number of sexual partners they have had, to help identify those at risk.