This got me off on a side-track when I started to think about how to phrase this. I mean, English has a slew of words for someone who is in need of food (EG: starving, hungry, famished), but very few words are coming to mind for the over-fed side of the spectrum that aren't compound words, nor can they be easily applied to something else.
Sure, starving, hungry, and famished can also be applied to knowledge instead of food, but I'm rather sure it's comparing it to the food-origin. Mirriam Webster lists these antonyms for "hungry":
Antonyms: full, satisfied
Near Antonyms: engorged, glutted, gorged, overfed, overfull, replete, sated, satiated, stuffed, surfeited
Now, most of those seem to work, but can be applied to other things. Sated/Satiated? Can't that also just mean appeased? Stuffed could be in the taxidermy sense. Full could mean "not partial". Engorged could mean swollen. Replete can just mean well-stocked (I think?) Overfed and Overfull are just compound words and not, eh.. whatever something that isn't a compound word (like how hungry, famished, and starving aren't compound words).
Glutted seems about the only one that's a stand-alone word for "well-fed".