I believe that we have two ways.
1. To leave the regulation of the abundance of our species "nature". It's disease, hunger, war.
2. Develop at least an elementary program of population regulation through laws, rules, ethics.
Like the one-child rule in China?
I get your point but it somehow feels ethically immoral..
If we all changed to a vegetarian diet we could feed a lot more people. That's a fact
Why not to change on eating each other?

To be serious, the problem with overpopulation touches some regions and the rest of world is not overpopulated. Look at some countries in Europe, they solve their problem with old society by inviting immigrants.