I have been hungry and thirsty and what I did never surprised me. My point was that the Earth has nearly attained these population levels (quick check - currently 7.2 billion) without drastic consequences.
Ah, my mistake... although, regarding Soylent Green (vs. the non-cannibalistic story it was based off of "Make Room! Make Room!"), the primary premise was ecological collapse or loss of resources (and population) respectively that was the source of the problem. Overpopulation was a sidebar in Soylent Green to simply exasperate the problem.
In any case, I see your point.
K2