Well that's the case in the US, where cases of oral cancer have dramatically risen by 225% since the 1970s. And while smoking and other forms of tobacco use is the leading cause of oral cancer worldwide, the scientists claim these have been overtaken in the States by unprotected oral sex.
The cause, say the experts, is the human papilloma virus (HPV). The higher the number of partners you've had unprotected oral sex with, say Ohio State University researchers, the greater your risk of contracting the virus, which experts claim may lead to HPV-related head and neck cancers.
The findings have just been presented at a meeting of the American Association for the Advancement of Science in Washington.
HPV is strongly linked with cervical cancer, which is why teenage school girls are currently being vaccinated against the virus in this country and the US. And now medics are calling for boys to be vaccinated too in an attempt to reduce the number of HPV infections (according to statistics from the US Centers for Disease Control and Prevention, half of all sexually active US citizens will contract HPV at some point in their lives).
According to Cancer Research UK, oral cancer is more common in men than women in this country. But whereas 50 years ago the ratio of men to women with oral cancer was 5:1, today it's less than 2:1.
Did you realise having unprotected oral sex could be a risk factor for oral cancer?