How the potato got hot

The potato's greatest champion, however, was Antoine-Augustin Parmentier, a French scientist. While serving in the army in the 1760s, he spent three years in a Prussian jail, where he subsisted almost entirely on potatoes and became convinced of their merits. On his return to France, he wrote a prize-winning essay touting potatoes as "foodstuffs capable of reducing the calamities of famine," and convinced other scientists and doctors of their benefits.

But the public was unmoved until Parmentier arranged a series of publicity stunts. He organized a potato-heavy birthday banquet for King Louis XVI, for example, and persuaded the king's wife, Marie Antoinette, to wear potato flowers in her hair. She never actually said, "Let them eat cake," but she did endorse the potato.

But Parmentier's greatest trick was to post armed guards around the fields just outside Paris, given to him by the king, where he was growing potatoes. This aroused the interest of the local people, who wondered what valuable crop could possibly require such measures. Once the crop was ready, Parmentier withdrew the guards, and the locals duly rushed in and stole the potatoes. Several potato dishes are named after Parmentier in recognition of the success of his efforts.

Today, in an era when French fries are an icon of globalization, it is difficult to imagine that people were once afraid to eat potatoes. Yet many of the concerns they raised are now inspired by genetically modified foodstuffs. As with potatoes, they are seen by their critics as unnatural and possibly dangerous, though they also raise entirely new concerns about the extent to which agriculture has come under the control of large companies. At the same time, the technology is championed by scientists and politicians who regard it as a promising approach to increasing the food supply.

Might the threat of famine and war cause attitudes to shift again? Hardly a month goes by without a new report on the impact of climate change on global agriculture. A recent report from the International Food Policy Research Institute warned of the "dramatic consequences" for agriculture as variations in rainfall patterns cause droughts and floods, and coastal food-producing areas are inundated and yields decline. There have also been warnings of "food wars" triggered by shifts in the distribution of fertile land and water supplies. Meanwhile, the world's population is heading toward 9.2 billion people by 2075, according to U.N. forecasts. For most of the world's population, climate change will manifest itself as a food crisis.