This is one of the most frustrating things about how we, as a society, talk about obesity - we act like you can know something meaningful about a person's lifestyle and health from a single glance. Not to mention the related assumption that a thin body is inherently desirable and worth striving for.

A measurement like BMI, which is a great way of looking at a population, is a terrible way of understanding an individual, and the use of weight and BMI as a stand-in for health is infuriatingly wrongheaded.