The places where famine happens easily are mainly in developing countries in the South.
So, why does food hunger happen? The reason can be thought to be mainly three.
　
First, cereal crops can be livestock food.
The richer the lives become, the more requisition of meat increases.
In order to far up a barn animal 1kg, cow require 8kg, pigs require 4kg, and chickens require 2~3kg of cereal crops.
So, cereal crops are eaten not poor people but barn animals in developed countries.

Next, rich-poor gap can be considered to the cause.
While people become richer on a global basis, there is a big difference in buying capacity.
self-support would be difficult, and it should be hard to expand the export of foodstuffs without economic assistance.

Finally, the way of agriculture is also the reason of food hunger.
Many of developing countries are agrarian country, but in half of their farming land, they grow crops for export.
These commercial crops have highly productivity because they have grown on the richest farming land among developing countries from a historical angle when they are colonies.
But, they are absolutely for export, so they can’t be ease their hunger.
The cause of food hunger is related to the rich lives in the developed countries.