Metabolism

What I learned about weight loss from spending a day inside a metabolic chamber

One of science’s best tools for understanding obesity is debunking myths about metabolism.

By Julia Belluz@juliaoftorontojulia.belluz@voxmedia.com  Sep 4, 2018, 10:20am EDT

Photographs and graphics by Christina Animashaun

When scientists offer mice or rats a spread of junk food, they consistently find that only some overeat and puff out into little rodent blimps, while others maintain a normal body size.

A similar thing happens in people. In the US, and around the world, we are now overwhelmed with highly palatable, cheap calories. This has helped obesity rates soar on average. But not everyone overeats and becomes overweight, and not everyone who becomes overweight or obese develops illnesses like diabetes or heart disease. This individual variation — why we have different responses to extra calories and weight — is one of the greatest mysteries of modern medicine.

The best place to find answers is an 11-by-11.5-foot room in suburban Washington, DC. This summer, I spent a day there, one of fewer than 100 patients who will do so this year.