Random question to /r/fitness

This might seem like a stupid question, but for people that have six packs, do you have a beer belly when you sit down/lean forward/eat?

I'm home for the summer, and it's really hot in my house, so I usually hang around the house with my shirt off. I feel like I'm a pretty average fit guy... I'm 5'7" 145 lbs, and I've been doing SS for a while now so I'm starting to look pretty good - lifts are squat 210, DL 225, bench 145, OHP 85 in case you guys were curious. Lately when I eat dinner with my dad, he keeps telling me I need to eat less cause of my huge stomach (which only seems to show if I'm leaning forward and eating). He also thinks I should lose weight. Is he right, or is there something wrong with my posture, or is this normal?

I'm assuming I should just eat more and keep lifting... but I feel like making sure first. Thanks reddit!