A New Obesity Study About the Difficulty of Permanent Weight Loss

A new Obesisty study, involving a follow-up on contestants of the TV show, The Biggest Loser, highlights several startling truths about why it’s so hard to lose weight and keep it off for the approximately 71 percent of American adults who are overweight or obese. Here are some lessons anyone should take away from the study:

Don’t lose hope.

It would be tempting to read the findings of the Obesity study and throw your hands up. If people who are the best at losing weight are at risk of gaining it all back, what’s the point? 

But that would be the wrong message to take away from the findings, said Morton. A full continuum of obesity care is out there, and these weight loss methods include dietary counseling, medication, temporary gastric balloons and bariatric surgery. The sooner you reach out for help, the more chance you have of losing the weight for good.  

“If you do have an issue with your weight, please don’t wait, and please don’t despair,” he concluded. “There’s a lot of solutions out there that can help folks, and what this study shows is that people can be helped if they seek out treatment sooner and they have lifelong maintenance help.”

Obesity is a chronic condition that requires lifelong maintenance.

 A few key components to help maintain weight loss include a new way of eating that you can stick to for life, a sustainable exercise routine that doesn’t put you at risk of injury, at least seven hours of sleep a night and stress management strategies, said Dr. John Morton, chief of bariatric surgery at Stanford Health Care. Finally, following up with a professional as you figure out your new life are crucial — at first on a monthly basis, and then down to quarterly meetings if you feel you’re getting a handle on things.

It takes a village of medical professionals to help a person lose weight safely, says Dr. Lawrence Cheskin of the Johns Hopkins Bloomberg School of Public Health. But the work doesn’t end once you hit goal weight: Cheskin’s weight loss patients continue to check with their clinicians at least once a month for an extended period of time so that they can iron out any post-program bumps in the road.

“The more frequently you follow up with people, the better their chance of sustaining weight loss,” he said. “As far as I know with ‘The Biggest Loser,’ when you’re done with the show, you’re done.”

Perhaps we should focus on health and weight maintenance, not weight loss.

The danger in waiting to take action against weight gain is that your body’s weight control processes are like a thermostat, explains Roseberry. Set it too high (by gaining weight) and you run the risk of that temperature becoming your new normal. If the room manages to get colder (through weight loss), that thermostat will kick in and work to get those temperatures up again.

“Your body actually fights you to go back to that weight you were at,” says Roseberry. And as “The Biggest Loser” study suggests, that “fight” can go on for at least six years.

It’s probably best to think about obesity as a something akin to high blood pressure, which can go down with the proper medications but will shoot back up if you stop taking the medicine, Morton added. Or think of obesity in terms of cancer: it’s better to nip it in the bud when the problem is small, instead of stalling treatment and letting the tumor spread.

“Don’t let yourself get too far,” Morton said. “If your BMI is about 30, it’s time to do something about your weight.”

While weight loss should be the goal if your BMI starts to reach unhealthy levels, even taking steps to maintain your weight accomplishes a great deal, because it prevents your body from getting used to that higher “set point” weight that could soon become its metabolic norm, Roseberry added.

“If we can find new ways to prevent more people from gaining weight and becoming overweight and obese, that would be a huge step forward,” he said. “And if we can focus more on health parameters than weight per se, I think whatever you can do to help increase your overall health is more important than your absolute weight.”

Losing weight can lower your metabolism — but that shouldn’t stop you.

Most people regain at least some of the weight they’ve lost. There are many possible reasons for this, like returning to one’s previous unhealthy levels of exercise and eating due to fatigue or boredom with the new healthy routine. But as the Obesity study illustrates, the more weight you have to lose, the more your metabolism rate and leptin levels decline. These two factors alone, along with other physiological processes that are not captured in the research, are relentless forces essentially trying to pull your body back to its previous unhealthy weight.

These physiological processes are relentless forces essentially trying to pull your body back to its previous unhealthy weight.

The metabolism decline makes sense; a person who loses weight is smaller than they used to be, and so requires fewer calories to fuel their body’s processes. But the researchers note that the study participants had a resting metabolic rate that was about 500 calories lower than you’d expect based on their body composition and age. And in fact, over time, that metabolism kept getting slower, especially in people who maintained the most weight loss. This is because the participants started off at very high weights (the average BMI was almost 50).

“We expect patients to have a reduction in their basal metabolic rate,” said Dr. Holly Lofton, an assistant professor of medicine and the director of the medical weight management program at NYU Langone Medical Center. “This is congruent with other studies that have looked not only at metabolism but changes in hormones that affect appetite, desire for food and hunger in people who have lost weight from diet and exercise.”

One thing the study does illustrate, poignantly, is that weight problems are not simply a failure of will but instead a chronic medical condition. These “Biggest Loser” contestants have heart and drive in spades as they demonstrated on the show, and if weight loss was only a matter of self-control, they would have no problem maintaining it. 

Re-gaining some lost weight isn’t necessarily a failure

If a crop of “Biggest Loser” contestants who participated in the study is representative of the entire alumni, the show’s intensive diet and exercise resources weren’t for naught: While all but one regained weight in the intervening six years, it was also true that 57 percent of the 14 participants maintained at least a 10 percent weight loss, noted the study researchers. This is a significant amount of weight loss for anyone to sustain, but this number is all the more impressive considering that participants in this study started off with an average BMI of almost 50. 

Past research about other weight loss groups show that only about 20 percent of overweight people maintain at least a 10 percent weight loss after one year. Another study that followed up with weight loss participants eight years after an intensive lifestyle change found that only 27 percent maintained a 10 percent weight loss. 

“The good thing about [“The Biggest Loser”] is that these individuals did manage to keep a significant amount of their weight off,” said Aaron Roseberry, an assistant biology professor and a member of the Center for Obesity Reversal at Georgia State University. “Yes, they did gain weight back, but they are still lighter and ultimately healthier than when they started the show.”

True as that may be, not every doctor agrees with the show’s methods.  

“From what I’ve seen of clips of the show, I have concerns about ‘the support’ — if you will — that is offered to the patients,” said Lofton. “It seems at times to be punitive, which is not what I support when I try to induce weight loss in my own patients.”

While all but one regained weight in the intervening six years, it was also true that more than half of participants maintained at least a 10 percent weight loss.

We know that hormones control hunger cues, but there’s not much we can do about it right now.

The more weight you lose, the lower leptin levels get, leaving you hungry. The study notes that leptin levels in “Biggest Loser” participants plunged from a starting average of 41.1 nanograms per milliliter to 2.6 ng/mL at the end of the contest. Six years later, those decimated leptin levels had recovered somewhat, but only up to 27.7 ng/mL.

Currently there are five FDA-approved medications on the market to aid in weight loss, but none of them is a replacement for leptin, one of the key hormones that create feelings of fullness. The New York Times notes that the pharmaceutical company Pfizer is conducting animal trials for a medicine that imitates leptin, but they’re still ongoing. If scientists achieve a replacement for leptin in people who have lower levels due to genes or weight loss, it would be an obesity gamechanger, says Lofton.

“If we had a medication that would help patients who have leptin deficiencies, that would be a breakthrough,” she said. “And then for the rest of us, who lose weight and have lower leptin, it would be something that could improve our weight maintenance results.”