Prime time TV is a bad place to learn science. There may be no better example of this than hit reality show The Biggest Loser, which wraps up its 14th season on Monday night.
If you're unfamiliar with it, the show follows a group of obese people as they attempt to lose weight and regain their health. The contestants maintain a grueling workout routine and eat a birdseed diet, all while being yelled at by attractive personal trainers. It's brilliant TV. The problem, however, is that the show is based on bad science and sends the wrong message to people who want to lose weight.
Obesity is one of the most intensely debated topics among scientists, no doubt about it. But most experts agree that there are two really awful ways to try to lose weight, and The Biggest Loser promotes both of them: starvation diets and excessive exercise.
Starvation diets have a series of detrimental effects. They cause rapid weight loss, subsequent weight gain, and psychological distress as a result of the fluctuation in body weight, according to multiple studies published in recent years. In 2011, for example, a team of scientists concluded that drastic calorie restriction can “have unintended consequences, contributing to food and body preoccupation, repeated cycles of weight loss and regain ... reduced self-esteem, [and] eating disorders...” Research has also shown that there are dozens of pesky biochemical factors working against dieters who starve themselves.
Unnecessarily rigorous exercise routines likewise can have unintended consequences. Moving around too much can be a source of chronic stress, which releases cortisol, a hormone known to promote fat storage, according to scientists at Harvard. Research also suggests that too much exercise is associated with higher rates of heart disease and high blood pressure, and people who expend too many calories, over 3,500 a week in this study, may die earlier than those with more moderate workout habits. Perhaps most importantly for the biggest losers and people who would emulate them, exercise, particularly too much cardio, has been shown to stimulate appetite and decrease metabolism.
Unsurprisingly, contestants on the show have endured all of these effects to some degree. A recent study looking specifically at contestants on The Biggest Loser found that they experienced a significant drop in resting metabolic rate, burning 504 fewer calories on average, thanks to an effect known as “metabolic adaptation.” And perhaps as many as 90 percent of the contestants on the show regain all their lost weight, according to US News.
LiveScience reported in 2010 that two contestants from season 8 owere hospitalized after collapsing during a foot race. Another contestant from season 9 was treated for exhaustion after trying to ride 26 miles on a stationary bike. The risk in all three cases was heightened because the contestants had been severely obese and inactive for many years, according to experts quoted in the LiveScience piece.
Researchers have also investigated how The Biggest Loser affects viewers. In one study, viewers expressed increased disdain for overweight people, even after watching just one episode. In a second study, viewers were more likely to think of obesity as a condition influenced mostly by lack of self-control. Finally, a third investigation found that viewers were less inclined to exercise because of how it's portrayed on the show. Images of people barfing and passing out aren't good motivators, apparently.
The gross inaccuracies perpetuated by the show are certainly annoying, but they're not unique by themselves. Pick any science topic, and I'll show you an example of pop culture screwing it up. What's most frustrating about The Biggest Loser is that it highlights the ridiculous lengths to which many Americans will go to no longer be fat, even if they could harm themselves in the process. Living in the supposedly progressive, tolerant society we do, that's a very revealing observation.