Keeping pounds off long-term is difficult for even the most successful dieter, and scientists may now be on the path to determining why.
A study published recently in The Journal of Clinical Investigation shows that high-fat foods cause damage to the hypothalamus – an area in the brain responsible for hunger, thirst and the body’s natural rhythms and cycles – in rodents.
“These are really important papers that begin to push the idea out that we’re not in control as much as we think we are,” says Dr. Steven R. Smith, co-director for the Sanford-Burnham Diabetes and Obesity Research Center, who wasn’t involved with the study.
However, Smith says researchers must first determine if the scarring happening in the rodent models will translate to the human condition. Not everything that scientists observe in rodents also applies to humans, of course, but it is a starting point.
“This is the tip of the spear. We’ve been talking a lot about diet and willpower and exercise and this sort of thing. This is radically different [thinking] – that diets can actually re-program the structure of the brain.”
The human body is designed to regulate how much fuel is stored as fat through a process called energy homeostasis, the study’s lead author Dr. Michael Schwartz says. For a normal-weight person, that’s good. But once a person becomes obese, his or her body seems to want to stay at that new weight permanently.
“That’s the biggest problem with obesity treatment,” says Schwartz, director of the Diabetes and Obesity Center of Excellence at the University of Washington. “Obese people can lose weight, but they have trouble keeping it off.”