A Weight Gain Theory of Everything

By now you’ve probably heard about a new class of drugs called semaglutides. They were recently approved by the FDA for weight loss. In clinical trials, participants lost astonishing amounts of weight. And so long as they continued taking the drug, they kept it off. Additionally, people taking semaglutides dramatically lowered their risk for heart disease, diabetes, and numerous types of cancer.

Whether or not these drugs remain cost prohibitive for many people (they currently run $15,000 per year) is yet to be seen. The same goes for long-term side effects, though similar drugs have been used safely for over a decade.

My interest here is not in weight loss, per se, but rather in the dramatic impact these medications have and the mechanism by which they work: decreasing appetite and food cravings in the brain.

On a recent episode of The Ezra Klein Show, the obesity neuroscientist Stephan Guyenet spoke eloquently about the evolutionary mismatch. In short, for well over ninety-nine percent of our species’ history we lived amidst scarcity. Abundance is a recent phenomenon, and even newer is a science that allows people to engineer the most enticing foods — along with a billion dollar industry that profits from it. As a result, the majority of people in America find themselves overweight or obese.