"mere sustenance" is correct and usable in written English.
It is an idiom that means something is just enough to get by, to survive, or to satisfy basic needs. For example, "The wages he earns from his part-time job are barely enough to provide him with mere sustenance."
It will never give me a healthy relationship with food – it will not make it into mere sustenance to me.
"I am an artist, and artists need more than mere sustenance to intelligently express themselves," she explained, adding, in answer to a question, that her comment was not meant as self-parody.
It's difficult to overstate Beard's far-reaching influence: He pioneered food TV with the first-ever network cooking series in 1946; he authored nearly two dozen books and hundreds of magazine and newspaper articles on gastronomy; through it all, his work inspired home cooks to no longer see food as mere sustenance but as a delightful, indulgent form of entertainment.
It's difficult to overstate Beard's far-reaching influence: He pioneered food TV with the first-ever network cooking series in 1946; he authoured nearly two dozen books and hundreds of magazine and newspaper articles on gastronomy; through it all, his work inspired home cooks to no longer see food as mere sustenance but as a delightful, indulgent form of entertainment.
Crime novels, fantasy and science fiction were segregated because they were considered mere entertainment bereft of moral sustenance, also because they were perceived as appealing to non-mainstream citizens: uneducated, working-class, possibly even "ethnic".
Scattered across the island, seven miles at its widest, are a number of other guesthouses where the beaches are blessedly empty but a mere 20-minute walk to the civilizing sustenance of Velha Boipeba.
Moreover, even the mere confinement in laboratory cages deprives chimpanzees of basic physical, social and emotional sustenance.
Sustenance and titillation.
We needed the sustenance.
