Stevia really helps normalize the blood sugar and it satisfies and reduces cravings for sweets. This mainly means eating organic foods, drinking spring water, not tap water, putting a filter on your faucets to eliminate chlorine and chemicals from the water you wash and bathe in. Also eliminate chemicals from your home. Pesticides, solvents, glues, perfumes, laundry soaps, dish soaps, cleaners and so on should be eliminated or replaced with non-toxic versions. You can do an awful lot of good cleaning with things like white vinegar, baking soda and borax.
Boric acid is a safe pesticide.
Companies like Planet Solutions make non toxic cleaners as well. Some kids have unhandled allergies which can set them off mentally. The allergies may not even be known about by the parents or ordinary doctors. These can be handled as well, and should be. If I had a kid for whom doing the steps 1-4 above did not resolve the problem, I would consult Dr. Doris Rapp, M.D. in New York, a famous specialist in Environmental Medicine.