Well yes, obviously you'd try to reduce the birth rate nicely first, and maybe that's a complete solution (to a problem you suggested), but that doesn't answer the question.
I'm asking what you do if population growth starts to outpace food production despite your best efforts? Do you start killing old people, or do you stop letting people have babies?
Neither. I'd prefer one smart enough to understand the demographic economic paradox and successfully raise the standard of living so that the problem of overpopulation solves itself naturally.
https://en.wikipedia.org/wiki/Income_and_fertility