You may have seen the headlines about 14 of the “Biggest Loser” contestants who were followed for 6 years and how they gained their weight back…well actually one did not gain back their weight. However, five contestants gained all their weight back to within 1 percent of their previous weight and the rest gained back 70 percent of the weight they lost. I thought that this would be a good time to cover the “set-point” theory related to our body weight.
We all carry genes that are designed to preserve our species by encouraging us to eat foods that are high in fats and sugars, foods that are caloric dense. This is how we and other species survived famines eons ago. This gene coupled with a learned environment that teaches us the love of ice cream, pizza, fried chicken, French fries, pecan pie, Oreo cookies and the like is a deadly marriage. When this “fat” gene interacts with the environment that we live in where advertisements of high fat, high sugar and salt based foods are common place on the television, the result is the perfect storm or in scientific terms the perfect phenotype that leads to obesity. This “fat” gene coupled with a caloric rich environment has led to the obesity epidemic that we now face.
In the study the “Biggest Loser” contestants went through a significantly labor intensive exercise program with a suggested dietary intake. The environment that they were in was controlled (which is the biggest problem). Why?.. because the contestants at some point in time must return to the same environment which led to their obesity problems. The very place that carries the same food temptations, and family or friends that enable their behavior, without a personal coach or the lens of a camera following them everywhere to hold them accountable. The genes and the learned behaviors that these participants carry without some constant management from an outside source will return each of these contestants to behaviors of old and unfortunately to their previous body weight.
If we were to take these same contestants and place them in a village in a West African country like Burkina Faso where they literally live off the land eating roots, beans and other plant based diets….these contestants would maintain their weight loss and would even continue to lose more weight until they achieved a stable weight corresponding to their gene interacting with that environment. The environment interacting with their gene coupled with past learned behaviors will dictate their actions. Obesity is a disease of addiction and to expect these contestants to return to an environment where the food industries rule is like expecting a drug addict to kick their habit, when every time they turn on the television they are bombarded with an advertisement about an addictive drug or drive by a billboard enticing them to indulge in the drugs of their choice.
The research of the ‘Biggest Loser’ focused on the reduction in the metabolism of each contestant. Indeed the contestants had a significant reduction in their metabolism which was to be expected. The resting metabolic rate (RMR,) which is how many calories are expended at rest, is correlated with the lean body mass each contestant carries. When weight loss is experienced there will be a reduction in body fat as well as the lean body mass. The amount of lean body mass that is metabolically active will dictate the RMR. Interestingly in the study of the ‘Biggest Loser’ contestants weight regain was not significantly correlated with metabolic adaptation at the competition’s end. This suggests that each contestants phenotype (their gene interacting with their environment) was primarily responsible for their weight regain.
In my next article, I’ll cover the importance of maintaining as much lean body mass during a weight loss program.