Absolutely it's the thc. Cannabis 101 is that cannabis blocks the part of your brain , can someone look up which part, the tells you you're full . If you've smoked then just ate you'll still feel full verses if you've ate first, you won't feel full. I've heard of people losing body fat and I've done it myself while consuming thc. But I'm sure you can still get ripped while consuming if you've got many, many other factors in place. Just don't blame cannabis for overeating, it's you that made the choice to consume both cannabis and excess food. That said too many people drop calories too low and this stalls metabolism so maybe if you have the willpower and discipline smoke one or two days a week or higher carb , calories days. Just an idea. You do the work or hire or get advice from someone who is intelligent in this area.