I used to weigh well over 300lbs, and I eventually took up a hobby that made me want to lose it badly enough to go through the trouble of making my body eat half of itself.

I don't get to order pizza. I don't get to pick up something from a fast food joint on the way home. I can't go to a restaurant with friends. I have to avoid gatherings where free food will be present. I dread the days a coworker brings in donuts. I've had to get used to going to bed hungry. I usually don't have much energy at all because my caloric intake has to be restricted so much to prevent me from gaining weight back, so I take stimulants to suppress appetite and make it possible to get through the day without falling asleep at my desk. I am a slave to the scale.

So I guess what I'm saying is that I disagree with your statement. Oh, it sucked to be fat alright, because people treated me like shit just for existing and because it was embarrassing every time I broke a chair, but I wouldn't say I had less energy and I definitely wouldn't say I had less fun either.