Soylent gets its name from a sci-fi novel.
Soylent — that meal-replacement drink that's a Silicon Valley favorite — got its name from the science-fiction novel "Make Room! Make Room!" which is about how population growth depletes the world's natural resources. In the book, soylent is a blend of soybeans and lentils.
"Roth takes Soylent's oceanographic reports to a group of researchers, who agree that the oceans no longer produce the plankton from which Soylent Green is reputedly made, and infer that it is produced from human remains, the only conceivable supply of protein matching the known production."
Hope this is not what is the protein in Soylent :O