Our battle against weight gain seems never ending. We are constantly making a mental note of the foods we eat and whether they are healthy for us. We feel bad when we eat something particularly calorie heavy and try to compensate by eating healthy the next day or spending more time exercising. However, according to a new study, our brain may be working against us when we try to shed pounds through dieting, preventing us from burning fat.
The human body is exceptionally efficient. It is able to break down and process the food we eat into usable energy, to regulate temperature, and even store excess energy in fat.
Sadly, this appreciation of the intricacies of the human body is lost on most people, especially when understanding how to best take advantage of normal bodily processes. But it’s also our body’s implicit survival tactics that hamper our ability to lose weight.
Dieting through pure calorie restriction is perhaps the least efficient method of losing weight. While it does work, it may take longer and result in more misery in the long run. When you restrict the amount of food you consume, your body assumes the food is not available to you, rather than it being a conscious choice. So, to increase survivability, our body decides to stop burning calories.
“Weight loss strategies are often inefficient because the body works like a thermostat and couples a number of calories we burn to a number of calories we eat. When we eat less, our body compensates and burns fewer calories, which makes losing weight harder. We know that the brain must regulate this caloric thermostat, but how it adjusts calorie burning to the amount of food we’ve eaten has been something of a mystery,” says Dr. Clémence Blouet from the Metabolic Research Laboratories at the University of Cambridge.
Using mice models, researchers were able to identify a new mechanism by which the body adapts to low caloric intake and limits weight loss. Neurons or brain cells in the hypothalamus called agouti-related neuropeptides (AGRP) neurons are known for playing a major role in the regulation of appetite.
When AGRP’s are activated, we feel hungry. When inactive, we don’t. Interestingly, when no food was available during AGRP activation, they spared energy, limiting the number of calories burned.
“While this mechanism may have evolved to help us cope with famine, nowadays most people only encounter such a situation when they are deliberately dieting to lose weight. Our work helps explain why for these people, dieting has little effect on its own over a long period. Our bodies compensate for the reduction in calories,” said Dr. Blouet.