You can even take a more direct route and make the body just burn more energy. Works perfectly well, technically doesn't have any side effects, though you have to take into account that burning energy results in heat.

And in all cases homeostasis is just going to attempt to return to normal as soon as possible. You need to somehow break the loop of your body wanting more energy to maintain its weight. This is a lot trickier because the checks and balances are everywhere and affect everything.