They promise to give you more energy or to improve your mood, but a debate has opened over the safety of the increasingly popular energy drinks like Red Bull and Rockstar.
Sales for these so-called functional foods are expected to hit $50 billion a year in the next four years, according to the Nutrition Business Journal. But the Food and Drug Administration has some serious questions about the products and has ordered a hearing for Dec. 5.
The drinks are partly a response from the food industry, which faces competition from products that include herbal and vitamin supplements.
"Consumers are looking for foods that provide both the benefits of nutrition as well as some benefits beyond what we all understand from vitamins and minerals and basic nutrition," said Robert Earl of the Food Products Association.
Rockstar's ingredients include taurine, caffeine and something called milk thistle. Its makers state on the can that the drink is "scientifically formulated to speed recovery time" but in small print says those statements have not been evaluated by the FDA.
For six years, critics have asked for more regulation of the functional-food industry, with Bruce Silverglade at the Center for Science and the Public Interest calling some of these items nothing more than "21st century quackery."
"Snake oil salesman wrapped up in a modern package," he said.
Questions arise as to just how safe the drinks are.
A dietitian from the International Food Information Council, which is funded by the agriculture industry, said drink cautiously.
"Moderation, I think, really is the key here," said Wendy Reinhardt Kapsak. "Any one of these products by themselves isn't likely going to cause a safety concern."
But, she added, it "could potentially have some negative side effects."
Critics will get their formal say when the government holds its hearings on whether these functional foods are what they say they are.