It's no secret – losing weight is hard. Keeping it off is harder. But is there a reason obese people struggle so hard to keep the kilos at bay? Could it be that their bodies are actually working against them? A very interesting piece in the New York Times looked into just that, and if you're interested in the topic, it's well worth a read...
While researchers have known for decades that the body undergoes various metabolic and hormonal changes while it’s losing weight, the Australian team detected something new. A full year after significant weight loss, these men and women remained in what could be described as a biologically altered state. Their still-plump bodies were acting as if they were starving and were working overtime to regain the pounds they lost. For instance, a gastric hormone called ghrelin, often dubbed the “hunger hormone,” was about 20 percent higher than at the start of the study. Another hormone associated with suppressing hunger, peptide YY, was also abnormally low. Levels of leptin, a hormone that suppresses hunger and increases metabolism, also remained lower than expected. A cocktail of other hormones associated with hunger and metabolism all remained significantly changed compared to pre-dieting levels. It was almost as if weight loss had put their bodies into a unique metabolic state, a sort of post-dieting syndrome that set them apart from people who hadn’t tried to lose weight in the first place.
That's not to say that overweight people can't slim down and stay that way. The results just indicate that it may be harder for them. While at 60kg, I can maintain my weight by eating a certain number of calories and doing a certain amount of exercise, someone who gets down to 60kg from an obese weight may find they have to eat less calories and workout for longer in order to maintain the same weight – because their bodies process food differently and respond to exercise differently.
It's preliminary research, but it could go some way to explaining just why it's so hard for obese people to lose weight and keep it off.