Douglas told a newspaper journalist that drinking and smoking don't cause mouth and throat cancer, but the HPV infection-transmitted by oral sex-does.
But researchers from Johns Hopkins University couldn't find any evidence to support the claim when they analysed the health of 88 women and six men whose partners had HPV-related throat cancer.
Six of the partners had oral HPV infection, but, of those, just two had HPV-16 infection, the type that is associated with cancer, but at very low levels, and it wasn't detectable at all a year later.
The researchers, led by Gypsyamber D'Souza, aren't sure why the infection should disappear, but think the immune system can clear the body of any infection if the person is faithful to one partner.
They say that people don't have to change their sexual practices even with partners who already have the HPV infection, they say. It's a different story, however, if you are sleeping with many partners.
(Source: American Society of Clinical Oncology annual meeting, June 1, 2013).