Nutrition: Major Government Fail?

Americans are getting used to failures by government experts. Government economists have a dismal forecasting record. Government actions and advice during the pandemic were often misguided. And dozens of former government intelligence experts got the Hunter Biden laptop story wrong.A less recognized but also important failure may be in nutrition. Federal experts appear to have issued faulty advice for decades, even as American obesity exploded from 15 percent in the 1970s to 42 percent today. Federal guidance on nutrition has a large influence on health practice across society. Some researchers argue that Americans have generally responded to the guidance, yet obesity has nonetheless soared.A clue to shortcomings in federal nutrition guidance comes from calorie data. A new U.S. Department of Agriculture (USDA) study shows that average daily calorie intake increased 21 percent from 1977–78 to 2003-04, and then started trending down. By 2017–18, calories were up 15 percent from the 1970s, but as the study notes, “the rise in obesity rate outpaced the increase in calorie intake.”In a 2022 article, Professor of Nutrition Dariush Mozaffarian noted that “over the last 20 [years] we are not eating more calories, nor exercising less, but are still becoming more obese.” As average calories have dipped, the obesity rate rose from 31 percent in 2001–2002 to 42 percent today.How can that be? Obesity is caused not just by the amount we eat but also what we eat. Generally, the government advised us to emphasize carbohydrates and deemphasize protein and fat, as shown in the food pyramid. But some nutritionists are now saying that was backwards. As a libertarian, I don’t want the government telling us what to eat, and our diets may have been better if that had been the case.Like government experts, private‐​sector experts get things wrong. But the government uses mandates and subsidies to impose its will, and its strong positions often displace other views. In a presentation at Cato, author and science journalist Nina Teicholz discussed the government’s flawed nutrition standards and the harm she believes they caused. She observed, “the level of certainty you need to have for public policy of an entire population ought to be very high,” and federal directives on nutrition fell far short of that level.The chart shows average daily calorie intakes of Americans, based on the new USDA data. Carbohydrates are up 22 percent since the late 1970s, fat is up 12 percent, and protein is unchanged. It appears that we mainly want to look at carbs to explain the rise in obesity.