When the world was a simpler place, the rich were fat, the poor were thin, and right-thinking people worried about how to feed the hungry. Now, in much of the world, the rich are thin, the poor are fat, and right-thinking people are worrying about obesity.
Evolution is mostly to blame. It has designed mankind to cope with deprivation, not plenty. People are perfectly tuned to store energy in good years to see them through lean ones. But when bad times never come, they are stuck with that energy, stored around their expanding bellies.
Thanks to rising agricultural productivity, lean years are rarer all over the globe. Modernday Malthusians, who used to draw graphs proving that the world was shortly going to run out of food, have gone rather quiet lately. According to the UN, the number of people short of food fell from 920m in 1980 to 799m 20 years later, even though the world’s population increased by 1.6 billion over the period. This is mostly a cause for c
A. bring up some warnings.
B. tell the reader some new facts.
C. discuss a solution to a problem.
D. persuade the reader to keep fit.
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