As bearded dragons are omnivores, food items on their diet list include invertebrate and vertebrate animals and plant matter. The main insect bearded dragons eat is crickets, but they also feed on mealworms, earthworms, silkworms and grasshoppers. Adult bearded dragons can occasionally be given small mice. Plant-based foods includes mustard greens, dandelion greens, collard greens, parsley, escarole, carrots, squash, bell peppers, green beans and various fruits and berries.
Crickets fed to bearded dragons should be gut-loaded. This means they are fed nutritious food, which is then absorbed by the lizard when it eats the crickets. The crickets should also be dusted with a calcium and vitamin D3 supplement. The greens and other vegetables should be chopped up into small pieces to make them easier for the bearded dragon to digest. Greens with large leaves can also be attached to the side of the cage for the dragon to chew. Fruits and berries good for bearded dragons include papayas, mangoes, apples, grapes, bananas, cantaloupes and blueberries.
Bearded dragons can get impaction of the digestive system if they are overfed or if the insects they are given are too large or have hard exoskeletons. They should be given only small crickets. Mealworms should be fed to them after molting, when they are still soft. Young bearded dragons should be fed only as many insects as they can eat in 10 minutes. Wild-caught insects should not be fed to pet bearded dragons, because they may be contaminated by pesticide.