For people who are extremely overweight, a program of diet and exercise may seem like the healthy way to effect drastic weight loss, but a study of contestants on the popular reality TV show The Biggest Loser suggests that’s not true. It turns out that drastic weight loss is associated with a slow metabolism and with low levels of hormones that affect hunger. The Biggest Loser seemed to offer tremendous hope. People who struggled with extreme obesity — a BMI of 40 or greater — competed to lose weight in a short amount of time. They worked with teams of doctors, nutritionists, and personal trainers. The contestant who experienced the most drastic weight loss by the end of the season (just 30 weeks) won the competition. However, a study conducted after the end of the season showed that the contestants’ metabolism had slowed and leptin — a protein that regulates the appetite — had plummeted, leaving them constantly hungry. Over the next six years, hormonal changes conspired to make the contestants regain much, if not all, of the weight they had lost. A few gained even more than they started with. However, the truly shocking part was that their leptin and metabolism levels never rebounded to what they had been before the show. In fact, the more weight the contestants lost, the worse their metabolism became. The lesson learned from The Biggest Loser is that drastic weight loss in a short amount of time comes with a price. Whether you're trying to lose 10 pounds or 50, slow and steady is far more effective.
