When it comes to diet and exercise, it really is possible to have too much of a good thing. Pushing your body to extremes not only puts you at risk for injury; it can also permanently slow down your metabolism, making it harder for you to lose weight and easier for you to gain weight as soon as you stop your extreme dieting lifestyle.
Case study: The Biggest Loser
Not convinced? Ruining your metabolism has been featured on the small screen for years. Contestants from the hit TV show The Biggest Loser: although they were overweight, often even extremely overweight, at the beginning of the season, the contestants from season eight all had normal metabolisms when the season started. By the time it ended, "their metabolisms had slowed radically and their bodies were not burning enough calories to maintain their thinner sizes," according to an article in the New York Times.
The article discusses new research done by a federal research center that studied the effects of extreme weight loss by closely monitoring and studying the contestants from season eight of The Biggest Loser. The results are startling and frightening, especially for people who have gone through bouts of extreme exercise and dieting.
Why resting metabolism matters
Researchers focused on the contestants' resting metabolism, which measures how many calories a person burns when their body is at rest. They found that the contestants, after going through an extreme diet and exercise regiment, now burn up to 800 fewer calories than they should. This means they need to severely restrict their diets if they want to keep the weight off, which poses additional risks nutritionally.
“As long as you are below your initial weight, your body is going to try to get you back.” - Dr. Michael Schwartz
Researchers consider it normal for a person's metabolism to slow somewhat after they finish with a diet program. What they didn't expect, though, was that the contestants' resting metabolism would slow so dramatically or that their slow metabolism would last for so long. Even worse, their metabolism continues to slow down as the years go by, making it difficult to impossible for them to keep their weight off without resorting to even more extreme measures.
The takeaway for the rest of us
So what does this mean for those of us who are not reality TV stars? To begin with, it highlights the dangers of extreme dieting. Sure, you might lose a lot of weight in a short amount of time, but when your resting metabolism slows down permanently, you will find that you can't keep the weight off. You will need to workout harder than someone who weighs the same as you but has a normal metabolism. You also will need to consume fewer calories.
More research needs to be done to have definitive answers (for instance this study didn't include a control group of people who didn't go through extreme dieting). However, the results presented are enough to cause alarm for all of us. Resist the urge to try extreme dieting and exercise. Keep a healthy lifestyle by exercising regularly, staying hydrated and eating a diet rich in whole foods, lean protein and plenty of fruits and vegetables.