So weight gain is the sole determining factor for addiction, then. Not cancer, or nerve damage, or death by hyponatremia.
Sugar doesn't make people fat. Overeating and inactivity makes people fat. Addiction isn't about the mode of addiction. People don't get hooked on sugar, or cigarettes, or heroin, or even exercise-- those are just the means to the end, which is whatever random thing is going on in their brain, and releasing enough endorphins to manage it. People chase feeling. Donuts make them happy. Alcohol makes them forget... and makes them happy, maybe. Food is an easy addiction because it's readily available, and it works on everybody. My wife could never become a heroin addict, she has a severe reaction to any opiate.
I got fat by being lazy. Not doing is easier than doing. I got not fat by riding the hell out of a bicycle-- to the point that my wife would like to point out-- I'm probably addicted to it. I feel uneasy if I take a day off of the bike. Other forms of exercise don't suppress this feeling. I get up at 4-5am to ride some days, despite having gone to bed at 1-2am. My legs are pretty much sore all the time. But as I'm not gaining weight, must not be addicted.
__________________
