The best athletes in the world face some serious health issues, but you probably wouldn’t have guessed that bad teeth were one of them. A recent study has found that nearly 40 percent of football players in the United Kingdom have teeth that are nearly rotting, and it has a serious impact on their athletic performance.

The U.K. has never been well known for its affinity for dentistry, but the recent study confirms that bad teeth are a serious problem for athletes in the country. According to a report from Agence France Presse, when compared to the average Brit, footballers’ teeth are exceptionally bad.

According to the study’s head author, Ian Needleman of the UCL Eastman Dental Institute, some of the football players had such bad teeth that jaw infections were running rampant throughout England’s soccer leagues.

Given the high pay rate of many of these professional athletes, it is unclear why they are not seeking basic dental care. It may have something to do with the hectic schedule of a professional soccer player, or it could interfere with practicing or treating other health conditions that take priority over healthy teeth.

The study, which was published in the British Journal of Sports Medicine, found that roughly 37 percent of the footballers had ongoing tooth decay, and 50 percent had teeth that were eroded by acids in the mouth. A whopping 80 percent of the players also suffered from gum disease. Roughly one in six players reported pain in their mouth, and about 25 percent were sensitive to cold and hot foods.

A press release outlining the details of the study can be found here.