(PARIS-AFP) - Top athletes are often dogged by decaying teeth and gum disease, a performance-sapping problem in which sports drinks, high-carb diets and training regimes may play a part, specialists said Monday.

Experts from Britain and North America reviewed 39 published studies into the oral health of elite or professional sportsmen and women.

Decaying teeth affected 15-75 percent of the athletes, moderate-to-severe gum disease up to 15 percent and enamel erosion between 36 and 85 percent.

The figures add to a survey carried out at the 2012 London Olympics, where 46.5 percent of athletes admitted they had not been to the dentist in the past year, and 18 percent said dental problems had affected their performance in the past.

"Oral health could be an easy win for athletes, as the oral conditions that can affect performance are all easily preventable," said Ian Needleman, a professor at University College London, who co-led the new study.

Dental problems cause pain and inflammation, affect sleeping and eating, and can hit sporting confidence too, he said.

But, he added, "simple strategies to prevent oral health problems can offer marginal performance gains that require little or no additional time or money."

The study, published in the British Journal of Sports Medicine, said athletes faced intense dietary and training pressures, all of which took a toll on their teeth.

Saliva helps to protect teeth from erosion and decay, so dehydration during heavy exercise can increase the risk of oral ill-health.

Fast energy replenishment often means athletes use high-carbohydrate diets or guzzle sugary, acidic energy drinks, which without cleaning can boost the risk of tooth decay and damaged enamel.

"We do not want to demonise energy drinks and are not saying that athletes shouldn't use them," Needleman said.

"However, people should be aware of the risks to oral health and can take simple measures to mitigate these. For example, water or hypotonic drinks are likely to be more suitable for simple dehydration, and spit, don't rinse, after tooth brushing.

"For sports where athletes need a lot of energy drinks, high fluoride toothpastes and mouth rinses should be considered."