What if Brian's "no carbs after seven" rule wasn't just about keeping up with his "stud of Liberty Avenue" reputation but actually went a lot deeper than that. A lot of Brian's rules and ways of life have a LOT to do with how he grew up, and I believe there could be a very good story here.
What if growing up, limiting what he ate was a way for Brian to stay in control?
What if Jack went on about how expensive it was to feed a growing boy, especially one that "ate like a horse."
What if Joan made passing comments about his weight?
What if starving himself took away from the pain that Jack was inflicting on him?
WHAT IF WHAT IF WHAT IT!!!!