I'd say as with all things, anything is possible in a) moderation and b) small doses. My son enjoys a mini milk, which is about 15grams of carbohydrate so I can have one with him from time to time. The longer answer is for your friend to try small amounts and monitor his blood sugars, if he can get testing strips. I do feel that if I don't allow myself any treats, I inevitably fall off the wagon harder than if I allow myself something nice from time to time.