That's how many are expected to inhabit the world by 2050. Experts worry over looming food shortages.
The world is an odd place. A tight global food situation with record-high grain prices presents the possibility of increasing malnutrition, perhaps famine, in parts of Africa and South Asia. Yet an estimated 1.6 billion adults, about a quarter of the world's 6.7 billion people, are overweight, some of them obese.
As a result, chubby Americans are spending roughly $1 billion a year to lose a few pounds with special diets, treadmills, etc., while hundreds of millions in poor nations are scrambling to buy enough food to add a little weight. "You couldn't write any stranger fiction," says Joseph Chamie, former head of the United Nation's Population Division.
The possibility of a world food shortage is causing more and more concern. "It's likely to get worse in coming years," reckons Mr. Chamie, now research director at the Center for Migration Studies, a New York think tank.
His fear is partly based on the fact that the world's population is growing by about 78 million people a year, with projections of an additional 2.5 billion people by 2050 – a generation away.
"The most significant event of the 20th and 21st century is the growth of world population," Chamie says. "It has affected every life form on this planet."
There have been a few dramatic spikes in food prices in the past century. For instance, in 1972 the Soviet Union, anticipating a domestic crop failure, quietly cornered available grain supplies in the world, doubling prices of wheat, rice, and corn. Weather-related events have pushed up food prices at other times.
But these events were temporary. Using surplus stocks, emergency measures eased food shortages in some poor nations. A new crop restored an adequate supply.