Akademik

И поджарый живот без еды не живет
Any living being needs food to stay alive and be strong. See У сытого коня восемь ног (У)
Cf: The belly carries the feet (the legs) (Br.). Even rosy lips must be fed (Am.). A full belly makes a strong back (Am.). A man cannot live on air (Am.). The stomach carries the feet (Am.). When the belly is full, the bones are at rest (Am.). When the belly is full the bones would be at rest (Br.)

Русско-английский словарь пословиц и поговорок. . 2013.