"food" for anything, "food" in its widest sense, "that which nourishes an animal or vegetable," 1670s, from Latin pabulum "fodder, food, nourishment," from PIE root *pa- "to feed" + instrumentive suffix *-dhlom. Related Pabular; pabulary; pabulous.
Pablum (1932), derived from this, is a trademark (Mead Johnson & Co.) for a soft, bland cereal used as a food for infants and weak and invalid persons, hence its figurative use (attested from 1970, first by U.S. Vice President Spiro Agnew) in reference to "mushy" political prose.
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<a href="https://www.etymonline.com/word/pablum">Etymology of pablum by etymonline</a>
Harper, D. (n.d.). Etymology of pablum. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/pablum