I lost about 40lbs of fat while putting on about 15lbs of muscle over a 3 month period.

I did the hcg diet. This was early 2013. I had a strict diet of 1300 cal/day and a very short list of items I could eat. Most things are not allowed, including diet soda. I adhered to it strictly, and wouldn't eat a single chocolate chip. I did heavy weight training 6 days a week and drank tons of water.

Once the diet was done I slowly upped my calories and ate a moderate amount of normal food. I stopped eating fast food altogether, as well as sweets/snacks. I do have a weak spot for pizza though. 2 1/2 years later I'm still within a few pounds of my lowest weight. The purpose of the hcg diet is to re-program your body chemistry so you don't just bounce back up once you stop. It worked for me.