Before you take your next gulp of an energy or sports drink, think twice about what it might be doing to your teeth.

A study published in the May/June issue of General Dentistry found that increased consumption of these beverages—especially among adolescents—“is causing irreversible damage to teeth.” The drinks’ high acidity was shown to erode tooth enamel, the tooth’s protective outer layer, according to a press release from the Academy of General Dentistry.

“Young adults consume these drinks assuming that they will improve their sports performance and energy levels and that they are ‘better’ for them than soda,” says Poonam Jain, BDS, MS, MPH, lead author of the study. “Most of these patients are shocked to learn that these drinks are essentially bathing their teeth with acid.”

The study showed that damage to enamel was evident after just 5 days of exposure to sports or energy drinks. Energy drinks caused twice as much harm as sports drinks. “Damage caused to tooth enamel is irreversible, and without the protection of enamel, teeth become overly sensitive, prone to cavities and more likely to decay,” stated the press release.