All too many of us are guilty of seeing some kind of red mark, spot or bruise somewhere on our body, freaking out and believing that we're 10 minutes away from death - only for whatever it is to clear up just moments later, allowing us to return to daily life without that trip to A&E.
It usually just turns out to be a bite, a weird bit of sunburn or something equally as boring, but that wasn't the case for one man, whose mysterious red mark was thought to be down to something waaaaay more interesting.
Dentists in Mexico were stumped by a red lesion on the roof of the 47-year-old's mouth, and after quizzing the patient determined that it was likely to have been caused by performing oral sex. We're guessing a fair bit of oral sex, if it was enough to leave a mark.
The Daily Mail reports that the unnamed man wasn't even aware of the red circle, as he hadn't experienced any symptoms. However, when he opened wide for the dentists, it transpired that something strange going on inside his mouth.
Eventually, they agreed that the odd mark - which is known in the medical world as 'erythmea', by the way - was probably down to performing fellatio.
The medics wrote up their findings in BMJ Case Reports, where they said that more people should be aware that oral sex can lead to lesions in the mouth.
The team, which was led by Dr Luis Alberto Mendez, explained: "The contact of the palate with the penile glands may cause a haematoma due to blunt trauma."
They also added that the dilation of the blood vessels in the mouth caused by sucking may have also helped the mark form.
The man had visited the School of Dentistry at the Universidad de Montemorelos after he spotted that one of his fillings had broken.
But the dentists spotted the 'circular shaped erythematous lesion' (say that after a few drinks) and, upon questioning, the man admitted to being sexually active with men, as well as having recently used marijuana and cocaine.
He also added that he regularly performs oral sex, and that the most recent time it had happened was three days before his trip to the dentist.
The dentists continued: "With this information, we concluded the erythema on the soft palate was associated with the practice of oral sex."
Thankfully, the patient was told that he wouldn't need any treatment, and that the lesion would clear up on its own.
Well, if this is a lesson in how we should all probably go visit our dentist more often, then I don't know what is...
Featured Image Credit: BMJ/PA