The antonyms for the word "feasted up on" could be words like abstinence, fasting, and deprivation. Abstinence refers to the act of refraining from indulging in something that is typically pleasurable, such as food or drink. Fasting, on the other hand, involves voluntarily going without food or drink for a designated period. Deprivation suggests being denied something that is perceived as necessary or desirable. These words convey a sense of restraint, discipline, or self-control, which is the opposite of "feasting up on," which implies indulging, overindulging, or overeating. By using these antonyms, one can articulate the idea of avoiding overindulgence or exercising moderation.