I dont know. Ive carried fat and skinny, and Ive always found skinnier was a bit easier. Not that fat was hard. Just a bit less comfortable in general.
I think more than body type, your mental outlook/attitude on things is even more important. If you are self-conscious, act a little guilty, act like youre carrying a gun, etc, even at a subconscious level, it will look suspicious, to anyone paying attention anyway, and even to those who really arent. How you carry yourself is actually more important than how youre dressed and carry your gun.
You just need to find your gun a sweet spot, get your head right and to the level that the gun is just part of your everyday attire, and you pay as much attention to it, as the knives, wallet, light, etc, in your pockets. Things tend to go much easier at that point.