Meal worms have a hard exoskeleton, and are more difficult for herps to digest. That is why they are being regurgitated. When meal worms molt, they are easier to digest, if you feed them while they are still white. Meal worms aren't very nutritious. You might also try dubia roaches. They are more nutritious than crickets, and easy to culture at home, if you wanted a reliable supply of feeders.