Lead author Poonam Jain of the Southern Illinois University School of Dental Medicine said the high acidity levels in the drinks erode tooth enamel, the glossy outer layer of the tooth.
"Most of these patients are shocked to learn that these drinks are essentially bathing their teeth with acid," Jain said in a statement.
The researchers examined the acidity levels in 13 sports drinks and nine energy drinks.
To test the effect of the acidity levels, the researchers immersed samples of human tooth enamel in each beverage for 15 minutes, followed by immersion in artificial saliva for 2 hours.
This cycle was repeated four times a day for five days, and the samples were stored in fresh artificial saliva at all other times.
"This type of testing simulates the same exposure that a large proportion of American teens and young adults are subjecting their teeth to on a regular basis when they drink one of these beverages every few hours," Jain said.
The study published in General Dentistry found that damage to enamel was evident after only five days of exposure to sports or energy drinks, although energy drinks showed a significantly greater potential to damage teeth than sports drinks. In fact, the authors found that energy drinks caused twice as much damage to teeth as sports drinks.