The food industry has urged federal regulators to allow broader health claims on energy drinks, power bars and other so-called functional foods amid criticisms from consumer groups that those claims can be misleading.

Once a niche market, the foods have grown to be a $27-billion-a-year business, attracting consumer giants such as Atlanta-based Coca-Cola Co. and Nestle S.A. The term has been applied to everything from calcium-enhanced orange juice to energy drinks containing herbs like ginseng, ginkgo and guarana.