ANSWER:

These are traps of Satan to make people astray by showing these kind of tricky ‘Logic’. 

Those sugary foods would be dangerous for the diabetics whenever it would endanger their health and safety and not for normal people whereas smoking is haram for everyone as Allah has said that everything that is harmful for the body is haram and sugar in itself is not haram. 

I was telling to my friend that the thing which is harmful for the body is haram eg. Smoking etc. Then he questioned that if a diabetic patient eats sugary food is it also haram for him. Isaid no its makrooh but I couldnt give a logical reason. Please tell me the reason and way to give dawah in such cases.