60秒科学:可乐涨价 帮你减肥（在线收听）

今年纽约州提交的财政预算案中有一项引发热议：向汽水等高热量饮料征收“肥胖税”。若预算案得以通过，含糖饮料将面临每盎司1美分的额外征税。这将给州政府带来每年10亿美元左右的财政收入，同时敦促人们减少汽水消费。然而涨价是否真能使消费者望而却步，转而支持健康饮食呢?

Here in New York, the pending state budget includes one provision that’s probably making more news than the rest of the budget’s contents combined: a tax on nondiet soda and other high-calorie drinks. If the budget is passed by the legislature, sugary drinks would be slapped with an extra penny-per-ounce excise tax. The idea is to both raise money for the state—an estimated billion dollars a year—and motivate people to consume less soda. But do higher costs really get people to eat more healthfully?

A study published in the March 8th issue of the journal Archives of Internal Medicine [Kiyah Duffey et al, says yes. Researchers tracked the eating habits and health of over 5,000 young adults for two decades. They found that a 10 percent increase in the price of soda was associated with a 7 percent decrease in soda calories consumed. Higher prices were also associated with lower total calorie intake, lower body weight and improved insulin resistance.

The higher tax is, of course, a political decision, not a scientific one. But the science does support the idea that such sin taxes accomplish their healthful intent.