some people lack the enzymes to process and eliminate sugar. for some people any carbohydrate will trigger off an allergic reaction in the body and thus one becomes INTOXICATED,= any carb turns into sugar. so ( maybe not so hypothetically) many races/ethnic groups on the planet lack these enzymes; native american indians/inuit/several asian groups/the mongols/the samish people of the north. basically one might say that it is a kind of Sugar intolerance (quite bloodtype evident).
An allergy---an intolerance that develops into a disease with definite psychosocial consequences and often treated as psychological problem....when in fact it is a question of biochemistry and molecular biology-----not always but often. and coupled sometimes with a genetic predisposition.
do a livercleanse plus other detoxifying measures (saltwater cleanse for example) one can amazingly alter cravings of all kinds trhough the recognition of the origin of the imbalance.