Although it is widely held that infections and eating difficulties are hallmarks of advanced dementia,25 there are few prospective data on the incidence of these complications. Over the course of 18 months, more than half of the residents in our study had infectious episodes, and 86% had eating problems.
So 10 billion people is the uppermost population limit where food is concerned. Because it's extremely unlikely that everyone will agree to stop eating meat, Wilson thinks the maximum carrying capacity of the Earth based on food resources will most likely fall short of 10 billion.
Understanding Carrying Capacity. Human population, now over 7 billion, cannot continue to grow indefinitely. There are limits to the life-sustaining resources earth can provide us. In other words, there is a carrying capacity for human life on our planet. Carrying capacity is the maximum number of a species an environment can support indefinitely. Every species has a carrying capacity, even humans. However, it is very difficult for ecologists to calculate human carrying capacity. Humans are a complex species.