Very difficult to change eating habits. My son who is in his 40's now has been insulin dependant diabetic since 5. When I gave him his insulin and provided his food, his blood sugars were great. Of course at some point in life they decide to do what they want. After years of not taking care of himself, he now has neuropathy and other conditions related to his diabetes. He tries to really watch himself now but the damage is done. My advice to your son...take care of it NOW because nothing good will come of poor eating habits. I am just as bad...its very hard to stop doing what you like...just try and try hard!!