Weight Loss & Weight Gain: How Big of a Role do Genetics Play?
Have you ever experienced successful weight loss just to eventually gain some, most, or all of it back? Even if this scenario has not happened to you personally, you probably know someone who has gone through it. It can be extremely frustrating to devote so much time and energy to shedding the pounds, just to have it creep back on. So is there a science to losing the weight and keeping it off? According to research highlighted in a New York Times article that just may be the case.
In this article, author Tara Parker-Pope is able to relate to anyone who has been motivated to lose weight, just to have it return later on. Even while maintaining a healthy lifestyle, she has been unable to keep the weight she’s lost off. She mentions that it could very well be due to genetics, because many of her immediate family members have also struggled with weight loss and keeping it off. But it is still up in the air as to how much of a role genetics play versus the environment.
So is weight gain (and weight loss) pre-determined by your body and brain’s genetic makeup? Or does it come down to the environment you are surrounded by? Recent research, as discussed in this article, says that it could go either way.
The National Weight Control Registry tracked 10,000 people who have lost weight and kept it off. Rena Wing, a professor of psychiatry and human behavior at Brown University’s Alpert Medical School, helped create this registry with James O. Hill, director of the Center for Human Nutrition at the University of Colorado in Denver.
Wing says physiological changes probably do occur that make permanent weight loss difficult, but she says the larger problem is environmental. She says people struggle to keep weight off because they are constantly surrounded by food, food messages, and opportunities to eat. “We’ve taught ourselves over the years that one of the ways to reward yourself is with food,” Wing says. “It’s hard to change the environment and the behavior.”
Although the people in the registry used different methods for weight loss, there does seem to be a common denominator. In order to have lost the weight and maintain the weight loss, a person must eat fewer calories and exercise far more than someone who maintains the same weight naturally.
Kelly Brownell, director of the Rudd Center for Food Policy and Obesity at Yale University, says that while the 10,000 people tracked in the registry are a useful resource, they also represent a tiny percentage of the tens of millions of people who have tried to lose weight and keep it off unsuccessfully. “You find these people are incredibly vigilant about maintaining their weight,” Brownell says. “Years later they are paying attention to every calorie, spending an hour a day on exercise. They never don’t think about their weight.”
From a different perspective, Rudolph Leibel, an obesity researcher at Columbia University, believes that weight loss and the ability to keep it off is based on a biological system. For 25 years, Liebel and his colleague Michael Rosenbaum, have meticulously tracked about 130 individuals for a minimum of six months. The participants would stay at the research clinic where every aspect of their body is measured, including body fat, oxygen consumption, carbon-dioxide output, calories burned during digestion, exercise tests to measure maximum heart rate, blood tests to measure hormones and brain chemicals, and muscle biopsies to measure metabolic efficiency.
The Columbia University participants are eventually placed on a liquid diet of approximately 800 calories a day until they have lost 10% of their body weight. Once they reach this goal, they are put through another round of intensive testing as they try to maintain the new weight. The data generated by this research suggests that once a person loses about 10% of their body weight, they are metabolically different than a similar-size person who is naturally the same weight.
The results also found that the changes that occur after weight loss translate to a huge caloric disadvantage. In other words, for someone to maintain their weight loss, they must eat fewer calories than someone who is naturally the same weight. The study also found that people who have lost weight burn fewer calories during physical activity than a person who is naturally the same weight.
The brain also seems to respond differently to food after losing weight, as per data collected from the Columbia University study. “After you’ve lost weight, your brain has a greater emotional response to food,” Rosenbaum says. “You want it more, but the areas of the brain involved in restraint are less active.” Combine that with a body that is now burning fewer calories than expected, he says, “and you’ve created the perfect storm for weight regain.”
It is clear that there will need to be more in-depth studying done of varying degrees to find out what influences weight loss and maintenance. Eventually, this research may change the way people approach weight loss.
Meanwhile, Shane Diet & Fitness Resorts sticks to the basics: fewer calories in and the right amount of physical activity to burn those calories. Since 1968, Shane’s participants have found success with gradual and steady weight loss, as opposed to trying to lose the weight as quickly as possible. Experience has shown that it takes time to form a habit and good healthy lifestyle habits can change a person’s life permanently.