In a Word

http://commons.wikimedia.org/wiki/File:Daniel_Lambert.jpg

aletude
n. corpulency

gundygut
n. a voracious eater

“Imprisoned in every fat man a thin one is wildly signalling to be let out.” — Cyril Connolly, The Unquiet Grave, 1944

“Outside every fat man there was an even fatter man trying to close in.” — Kingsley Amis, One Fat Englishman, 1963