Do we get fat because we overeat, or because of the types of food we eat? That’s the question posed by the Energy Balance Consortium Study, described by Sam Apple for Wired magazine . Apple gives a fascinating picture of how the study was conducted: Two days a week, participants were locked into “tiny airtight rooms known as metabolic chambers,” where scientists calculated how many calories they burned by measuring changes in oxygen and carbon dioxide in the rooms’ air.

Their meals, delivered through vacuum-sealed portholes so researchers’ breath wouldn’t interfere with the measurements, were chemically analyzed to determine exact levels of carbohydrates, proteins and fats. (One site for the research was the metabolic ward at the National Institutes of Health in Bethesda.)

Twice a month, the subjects had their body fat analyzed through “dual-energy X-ray absorptiometry scans.” Their blood was analyzed for lipids and hormone levels. Stool samples revealed which bacteria were in their guts.

The study is one of the first to be funded by the nonprofit Nutrition Science Initiative, founded in 2012 by science journalist Gary Taubes and physician/researcher Peter Attia. NuSI’s mission, Apple writes, is to challenge “existing knowledge gathered in the past five decades of research . . . from studies marred by inadequate controls, faulty cause-and-effect reasoning and animal studies that are not applicable to humans.”

The initiative’s work is broadly aimed at cutting the U.S. obesity rate in half and the prevalence of diabetes by 75 percent in 15 years. It’s an ambitious goal, and Apple’s expansive, wide-ranging story about NuSI, its founders and its study is an eye-opening read.

The Center for Science in the Public Interest’s Xtreme Eating Awards went to nine "winning" chain restaurant meals especially high in calories, fat, sugar and salt. The Cheesecake Factory got three of them. (Tom LeGro/The Washington Post)