Ofcourse the major cause of food shortage is population. But that is too much of a simple explanation and people are now looking at reasons for the shortage, including the growing middle class in India that is apparently eating more now. India and China are easy targets for the US; they are scared of blaming Ethanol and losing blue state votes in the next presidential elections.
There is some sense in this theory; the more developed a country becomes, the more heavier it's people and it's food plate get. So in that sense, the fat person cannot blame anyone else that just joined the club. The McDonalds and Pizza huts are doing their part in these countries to bloat up the digestive tracts of these people and the resultant binge that the developed countries are all too well aware of.
The real culprit is actually our convoluted desire to protect the world while devouring it with a passion unseen in history. So we drive our SUVs with corn oil rather than using public transportation. Using potential food as oil and livestock feed ties these supply chains together and triggers additional food crisis. Use of Ethanol as a fuel works out great for US farmers that produce corn, but is not so good for Sorghum(Jowar) eating people around the world. Why? Because land used for growing Sorghum is now being used to make corn as it fetches a higher price. Good old economics driven by the need to produce a feel good fuel called ethanol.
The solution to the high prices and food shortage is to eliminate competition for resources that go after human food. These currently happen to be livestock and bio friendly fuel (and export, an economic and politicial activity).
So if you go vegetarian and use public transportation, you will eventually end up reducing food price in some bizzare part of the world and end up with a few more pennies or paisas in your pocket. Ofcourse the cow farmer and corn farmer is not going to be much happy about it.
The meat lover in you is probably objecting to this idea vehemently. Just be prepared to shell out more for meat. Plus the eco vegetarian will end up driving meat prices down, if the idea ever catches up. The idea does have potential, a lot of baby boomer flower powerettes happen to be eco vegetarian.
Going vegetarian for new folks can be tiresome and there can be health risks; make sure that you eat pulses so that your protein intake remains at recommended levels. And be prepared for the pangs of desire if you are an eco-vegetarian and do not have any spiritual component to your vegetarianism! We promise to look away if you go for the occasional indulgence!