And in all that time, no nation has reduced its obesity rate. Not one.

The problem is that in America, like everywhere else, our institutions of public health have become so obsessed with body weight that they have overlooked what is really killing us: our food supply. Diet is the leading cause of death in the United States, responsible for more than five times the fatalities of gun violence and car accidents combined. But it’s not how much we’re eating—Americans actually consume fewer calories now than we did in 2003. It’s what we’re eating.

For more than a decade now, researchers have found that the quality of our food affects disease risk independently of its effect on weight. Fructose, for example, appears to damage insulin sensitivity and liver function more than other sweeteners with the same number of calories. People who eat nuts four times a week have 12 percent lower diabetes incidence and a 13 percent lower mortality rate regardless of their weight. All of our biological systems for regulating energy, hunger and satiety get thrown off by eating foods that are high in sugar, low in fiber and injected with additives. And which now, shockingly, make up 60 percent of the calories we eat.