Why It’s So Hard To Lose Weight
As thousands of dieters can attest, losing weight can be a losing battle. No sooner have you lost a few pounds, but your increased hunger soon makes you gain weight again. Keeping the weight off may be more difficult than losing weight in the first place.
A new study confirms this well-known phenomenon, showing that even up to a year after weight loss, your body's hormone levels and metabolism are conspiring against you to make you gain weight.
The Australian study, published in The New England Journal of Medicine and picked up in The New York Times, shows that after an initial weight loss, dieters who were trying to maintain their weight experienced increased levels of hunger even a year after their weight loss.
The study recruited 50 overweight participants who were otherwise healthy and put them on a restricted-calorie diet to help them lose over 10% of their body weight. (On average, participants lost 29 pounds in 10 weeks.)
After the weight loss, the participants' appetites and hormone levels were closely monitored. After losing weight, participants' hormone levels changed, causing them to experience greater hunger. For example, the hormone leptin, which tells the brain how much body fat is in the body, decreased, causing metabolism to decrease and the body to burn fewer calories. Low leptin levels also caused increased appetite. The hormone ghrelin increased, causing an increase in hunger.
Although it is known within obesity research that levels of hormones that control metabolism and appetite change after weight loss, the study is one of the first to show such a long-term effect. Even a year after the initial weight loss, participants in the study still had changed hormone levels, which pressured their bodies to regain weight. In fact, most participants regained almost half the weight they had lost. A year after the initial weight loss, dieters said that they felt hungrier than they did before the study began.
Researchers emphasized that condemning dieters for regaining weight they have lost is the wrong response, since there is such a strong, long-term biological urge for the body to gain back lost weight. Losing weight and keeping it off are fundamentally different processes, and in today's fight against obesity, there needs to be more long-term research into how to maintain weight loss. One future option may be to dose dieters with hormones to prevent them from regaining weight.
In the meantime, it is better not to gain weight in the first place than try to lose and keep off excess weight.