Estee,
What scripture(s) would support this?
Scriptures? They "don't need no stinkin' scriptures" to support their ad naseum rules and regulations....
But, yes, I get your point.....actually, same line of "thinking" that's behind the Watchtower ban on use of tobacco, have to keep our bodies clean and well-kept in keeping with our dedication, etc. etc.
Then, too, they could employ typical Watchtower reasoning and emphasize the bad example of fat, overweight King Eglon who had to be slain [by righteous Ehud, the fat-person hater....] 'cause he was so big. So overweight, in fact, that the assassin's sword got swallowed up inside him!! Watchtower: "Surely none of us would want to be like that!!!" (Judges 3)
Further Watchtower research reveals that Noah's getting drunk and "exposing" himself was not merely because he had too much to drink, but primarily because he was so overweight.
I think this could work...
---Dan