I'm on board for something like medication. I don't like the aesthetic of high fitness, so maintaining my PC's weight to be reasonable has been an exercise in reducing their appeal to me for gameplay reasons. =/
I hear you. I've just released a small update that adds a pharmacy to the High Street Shops town location. You can buy the weight loss medication here to speed your PC's weight loss up. Taking a walk at the park also burns calories without increasing your character's fitness.