Prognosis

A Weight Loss Program by Any Other Name Is Still a Diet

Companies push lifestyle changes instead of prescriptive eating to help people slim down, but it’s hard to overcome the yo-yo effect.

Illustration: Jasjyot Singh Hans for Bloomberg Businessweek

Dieting has never been fun, but it used to be more popular. About a quarter of US adults are on a diet, compared with 31% in 1991, says market researcher NPD Group. Sales of diet books, once reliable bestsellers, have fallen by almost half since 2004, according to publishing market data from NPD BookScan. People are moving away from restrictive eating because of a growing recognition of its limited effectiveness in keeping weight off, as well as greater advocacy for accepting all bodies, and more awareness about mental health considerations. And the $192 billion-a-year weight loss industry is responding to the shift.