Monday, May 2, 2016

How Wellness Programs and "Biggest Loser" Approaches to Weight Loss Could Semi-permanently Compromise Metabolism

The Brutal Reality of How Difficult It Is to Keep Unwanted Pounds Off After a Diet
  • 13 of the 14 contestants regained weight in the six years after the "Biggest Loser" competition
  • 12 of the 14 contestants appear to have a permanently or semi-permanently degraded metabolism
  • About one-third of contestants are now heavier than before going on the show
  • Bariatric surgery patients appear to generate a new, set-point for their weight within one year after surgery; 
    • one sixth the time it takes for strict diet and exercise 
    • meaning at least five more years of Leptin imbalance and supercharged hunger cravings

In 2009, contestants on NBC's Biggest Loser lost hundreds of pounds.  But they gained those pounds back.  A 6-year study of their struggles illuminates some frightening new findings about just how much of an uphill struggle it is to keep off unwanted weight.  This is from the New York Times:
[M]ost of that season’s 16 contestants have regained much if not all the weight they lost so arduously. Some are even heavier now.  
Yet their experiences, while a bitter personal disappointment, have been a gift to science. A study of Season 8’s contestants has yielded surprising new discoveries about the physiology of obesity that help explain why so many people struggle unsuccessfully to keep off the weight they lose. ... 
“It is frightening and amazing,” said Dr. Hall, an expert on metabolism at the National Institute of Diabetes and Digestive and Kidney Diseases, which is part of the National Institutes of Health. “I am just blown away.”
It has to do with resting metabolism, which determines how many calories a person burns when at rest. When the show began, the contestants, though hugely overweight, had normal metabolisms for their size, meaning they were burning a normal number of calories for people of their weight. When it ended, their metabolisms had slowed radically and their bodies were not burning enough calories to maintain their thinner sizes. 
Researchers knew that just about anyone who deliberately loses weight — even if they start at a normal weight or even underweight — will have a slower metabolism when the diet ends. So they were not surprised to see that “The Biggest Loser” contestants had slow metabolisms when the show ended. 
What shocked the researchers was what happened next: As the years went by and the numbers on the scale climbed, the contestants’ metabolisms did not recover. They became even slower, and the pounds kept piling on. It was as if their bodies were intensifying their effort to pull the contestants back to their original weight.
The entire story and accompanying graphs are riveting.  It goes on to show that even now, six years later, contestants bodies burn fewer calories at rest than they did before the show.  Their bodies have engaged in a continual revolt against the weight loss. These folks now need to eat anywhere from 400 to 800 calories a day less than a typical person of their size just to avoid gaining weight.  It is a sort of permanent metabolic handicap.

The ultimate conclusion is that once the weight is lost, a dieter must be even more vigilant than they were during the initial weight-loss phase.  And perhaps the most unnerving observation is that the only folks who succeed in keeping weight off are the ones who can just constantly live with being hungry and not succumb to those cravings - ever

This study showed that 13 of the 14 contestants regained weight in the six years after the competition. Four of those 13 are heavier now than before the show.  Similarly 12 of the 14 contestants have slower metabolisms today than they did six years ago, and burn fewer calories than expected (compared to other people of the same size) when at rest.

It's important to remember, however, this study investigates what happens after one engages in an extreme diet and exercise regime to lose significant weight quickly. The body fights vehemently to put that weight back on for as long as six years (could be for even longer or forever, but the study only addressed the six-year timeframe). What this study doesn't address is whether a slow sustained increase in exercise and better eating that leads to more gradual weight loss would have the same effect.

More on the story:
    Yoni Freedhoff is an obesity specialist (and critic of the Biggest Loser approach) who was not involved with either study. In an interview, he observed that, "The bariatric surgery patients saw the metabolic adaption reverted after about a year [as opposed to after 6+ years with the "Biggest Loser" approach, signaling just how destructive extreme diet and exercise are to metabolism]. So it would appear that the Biggest Loser-style weight loss is devastating to a person's metabolism compared to surgery." ...
    What isn't clear is whether a more gradual, non-surgical approach to weight loss would lead to the same outcome that the researchers found in the present study. "We don't have studies on people who slowly lost 40 percent of body weight and then tracked their metabolisms years later," Freedhoff said. "But we definitely know at this point that theBiggest Loser-style of weight loss is incredibly bad for a person's metabolism." ...
In contrast, a matched group of ... gastric bypass surgery patients who experienced significant metabolic adaptation 6 months after the surgery had no detectable metabolic adaptation after 1 year despite continued weight loss. It is intriguing to speculate that the lack of long-term metabolic adaptation following bariatric surgery may reflect a permanent resetting of the body weight set-point. 
Hat tip: to artist and good friend, Paul Hermann.