Trail mix. Potato chips. And now gum.

With a growing number of foods boasting added caffeine for an energy boost, the Food and Drug Administration says it’s time to investigate their safety.

The FDA’s new look at added caffeine and its effects on children and adolescents is in response to a caffeinated gum introduced this week by Wrigley. Called Alert Energy Gum, it promises “The right energy, right now.” The agency is already investigating the safety of energy drinks and energy shots, prompted by consumer reports of illness and death.

Michael Taylor, FDA’s deputy commissioner of foods, said Monday that the only time FDA explicitly approved the added use of caffeine in a food or drink was in the 1950’s for colas. The current proliferation of caffeine added to foods is “beyond anything FDA envisioned,” Taylor said.