Raging debate at Businessweek: CO2 is allegedly causing food scarcity; also, the biggest food related-threat to humanity is too much food

The Age of Scarcity - Businessweek

climate change is lowering yields

The Global Obesity Bomb - Businessweek

The U.S. is a heavyweight champion in fat. It has the most obese population of any industrialized nation. About two-thirds of all adults in the country are overweight and one-third are fully obese, according to the World Health Organization.

This, however, is yet another area where U.S. leadership is being challenged by upstart contenders from the developing world. Already, a larger proportion of people in Panama, Saudi Arabia, and six different Pacific Island nations are obese than in America. Growing obesity in poorer countries is a sign of a historic global tipping point: After millennia when the biggest food-related threat to humanity was the risk of having too little, the 21st century is one where the fear is having too much...
It may seem strange to be worried about too much food when the United Nations suggests that, as the planet’s population continues to expand, about 1 billion people may still be undernourished. Although there are good reasons to think the 1 billion estimate might be exaggerated, it is clear that hundreds of millions do still regularly go to sleep hungry. The issue isn’t so much that we can’t grow enough.

More Than [or less than] 1 Billion People Are Hungry in the World - By Abhijit Banerjee and Esther Duflo | Foreign Policy

Indian surveys bear this out: The percentage of people who say they do not have enough food has dropped dramatically over time, from 17 percent in 1983 to 2 percent in 2004. So, perhaps people eat less because they are less hungry.