If you’ve ever seen the television programs, The Biggest Loser and My 600-lb Life, then you know how difficult and heartbreaking the process of losing huge amounts of weight can be. Particularly in the case of The Biggest Loser contestants, they undergo exhausting and disciplined routines with trainers that involve limiting their calorie intakes and burning a substantial number of calories through vigorous exercise, often for three hours or more a day.
While many of the participants in these programs do initially lose considerable amounts of weight after dieting, exercise, or even surgery – sometimes losing hundreds of pounds – the threat always exists for them to regain some, if not most, of that weight. To determine the extent to which regaining weight actually occurs, a team of researchers writing in the medical journal Obesity tracked a group of 14 contestants from The Biggest Loser competition, performing diagnostic tests on them six years after their weight loss. Their body composition was measured and compared when they started the competition, at the 30-week point ending the competition, and again six years later.
Losing weight during the competition had dramatically slowed their metabolisms, according to the study, meaning their bodies stopped burning enough calories to maintain a thinner size. The result was that six years after losing the pounds, most had regained much of the original weight. Some were even heavier six years later than when they started the competition.
Contestant Danny Cahill, a land surveyor who had shed 239 pounds over seven months to win the Season 8 show in 2009, illustrated a typical experience. He dropped from 430 pounds to 191 pounds, and in his words, “I got my life back. I felt like a million bucks”. But, six years after winning the weight-loss competition, Cahill had regained more than 100 pounds, despite continuing to count calories and maintain an exercise regimen. Researchers in the study attributed his weight regain to a slower metabolism, and to his periodically losing the battle with constant food cravings. Those cravings could be explained by the hormone leptin, an appetite stimulant, whose levels drift up as weight is regained, triggering the urge to eat.