According to Dana Goodyear writing in The New Yorker (Aug 15&22, 2011):
Demographers have projected that by 2050 the world’s population will have increased to nine billion, and the demand for meat will grow with it, particularly in dense, industrializing countries like China and India. Last year–a year in which, according to the UN nearly a billion people suffered chronic hunger–the journal Science published a special issue on “food security,” and included a piece on entomophagy, the unappealing name by which insect-eating properly goes. Acknowledging that the notion might be ‘unappetizing to many,’ the editors wrote: “The quest for food security may require us all to reconsider our eating habits, particularly in view of the energy consumption and environmental costs that sustain those habits.’
From an ecological perspective, insects have a lot to recommend them. They are renowned for their small ‘footprint’; being cold-blooded, they are about four time as efficient at converting feed to meet as are cattle, which waste energy keeping themselves warm. Ounce for ounce, many have the same amount of protein as beef–friend grasshoppers have three times as much–and are rich in micronutrients like iron and zinc. Genetically, they are so distant from humans that there is little likelihood of diseases jumping species, as swine flu did. They are natural recyclers, capable of eating old cardboard, manure, and by-products from food manufacturing. And insect husbandry is humane: bugs like teeming, and thrive in filthy, crowded conditions.