ver the years of weight loss counseling, I always knew there was a lot more to losing weight than just doing an equation on paper to figure out resting metabolism. I would have overweight patients showing me their food diary and they are literally only eating 1200-1500 calories a day and exercising and still not able to lose weight.
I would scratch my head at why the math did not equate. I wondered if they were not telling the truth or if they were in the starvation zone and not able to lose weight. While either of those things could have been the case, we are now realizing that people can have metabolic adaptation and have permanently altered metabolisms.
The majority of participants experienced metabolic adaption where their resting metabolic rate was down by 400-500 calories per day.
Did you see the news recently about the study in the March 2016 issue of Obesity
? They followed 14 of the former contestants on the television show “The Biggest Loser” for six years after the end of the competition. They found that most of the participants did regain a substantial amount of their weight back–but compared to other interventions, they were successful. The most unfortunate thing was that the majority of participants experienced metabolic adaption where their resting metabolic rate was down by 400-500 calories per day. That means if they ate the same foods as someone who weighs the same as them and and exercised as much, they will steadily gain weight because their metabolism is now permanently slower.
Leptin hormone is also something the study monitored. You may be familiar with leptin, as it tells our brain that we have enough energy stored in fat cells. When someone is reducing calories or “dieting” and leptin levels go below the threshold, then your brain senses starvation.
At the beginning of the competition, the contestants had normal levels of leptin. At the finale, they had hardly any leptin which would have made them hungry all the time. As weight returned, leptin levels tried to normalize but only rose to about half of what they were at the start of the season. This lead to an increased appetite.
Weight loss and maintenance has always fascinated me because it is so complex. It is my hope that examples like this study can give researchers more insight on obesity so that we can have more tools and therapies available to help those who are working hard to maintain weight loss.
About the Author
Amy Campbell is a dietitian and certified diabetes educator. She currently works in public health in Lexington, Kentucky and has been working in diabetes for over seven years.