Most of the world consumes non vegetarian food significantly. This wikipedia article compares the virtual water requirements of various food products :- I am showing the water requirements just as an example. But even land required to produce 1 kg of beef/red meat must be greater than land required to produce 1kg eggs. So if human beings start shifting towards food products which require less resources for their production , but have similar nutritional value , maybe food shortage problems across the world could be lessened. By this logic , soy-milk fortified with calcium could be a substitute for cow's milk. Of course,changing habits of human beings especially food habits is a very tough job. Further, availability of food grains will also lead to increase in population. But still, the problem of hunger for the current world population remains unsolved. This could be one of the many solutions in a multi-pronged approach towards hunger reduction. There are also serious issues which need to be addressed such as black-marketing , in developing countries, which leads to hunger problems.