How oral sex can cause throat cancer as Michael Douglas shares how he reacted when he was diagnosed

After Michael Douglas shared how he developed throat cancer due to acts carried out in the bedroom, a study has revealed that oral sex can actually cause tumors.

The New Jersey-born actor and film producer was diagnosed with the devastating disease back in August 2010, and three years later he revealed in a bombshell interview with The Guardian that it was due to his excursions under the sheets.

The celeb told the news outlet he suffered from oral discomfort for months and made various trips to medical appointments, until a friend's doctor in Montreal examined his mouth and found the glaring problem.

"I will always remember the look on his face," Douglas, who is married to Catherine Zeta-Jones, said. "He said: 'We need a biopsy.' There was a walnut-size tumor at the base of my tongue that no other doctor had seen."

What caused it was going down on his partners during sex - the scientific word is 'cunnilingus'.

Michael Douglas, pictured with wife Catherine Zeta-Jones, is now cancer-free (Daniele Venturelli/Getty Images for The Red Sea International Film Festival)

"Without getting too specific, this particular cancer is caused by something called HPV [human papillomavirus], which actually comes about from cunnilingus," explained the two-time Oscar-winner.

He wasn't fibbing either, as one study published back in the naughties found strong evidence linking oral sex to the spread of human papillomavirus (HPV), which may lead to throat cancer in both men and women.

The research identified having multiple oral sex partners as the leading sexual behavior increasing the risk of HPV-related throat cancer, even more than smoking or alcohol use.

Douglas himself had a pretty wild time in the 90s.

The study involved 100 patients newly diagnosed with the disease and showed those with prior HPV infection were 32 times more likely to develop it. Risk also rose with smoking, drinking, and having over six oral sex partners.

Throat cancer can be attributed to having multiple oral sex partners in a lifetime (Getty stock)

In fact, those that had more than six oral sex partners in their lifetime were 8.6 times more likely to develop HPV-linked cancer.

However, science information officer at Cancer research UK, Dr Julie Sharp, noted that the study was rather small.

"There is conflicting evidence about the role of HPV, and this rare type of throat cancer," she said.

“As this was a small study, further research is needed to confirm these observations.

"We know that after age, the main causes of mouth cancer are smoking or chewing tobacco or betel nut, and drinking too much alcohol."

If you’ve been affected by any of these issues and want to speak to someone in confidence, contact the American Cancer Society on 1-800-227-2345 or via their live chat feature, available 24/7 every day of the year.