well-dieted
/ˌwɛlˈdʌɪətɪd/adjective
Having, or habitually adhering to, a good diet; especially subjected to or following a dietary regime designed to maintain or achieve good health or a healthy body weight.
Origin
Late 15th century; earliest use found in John Paston (1442–1479), landowner. Partly from well + diet + -ed.