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Why diets don't always produce results?
Last reviewed: 02.07.2025
Following a diet to lose weight becomes the meaning of existence for many. When choosing a new diet, we always expect the maximum result - but what do we get in reality? According to statistics, most dietary approaches turn out to be "failures".
Why does this happen? Why does a diet often not only fail to show the desired effect, but can also add a couple of kilograms?
A new experiment by scientists has helped explain why our bodies resist diets, and why changes in diet do not always lead to weight loss.
The popular periodical "eLife" reports: the pattern of loss of sensitivity of the organism to changes in nutrition is present not only in humans, but also in animals. Specialists from Cambridge conducted experiments on rodents - the results obtained were truly surprising.
As Professor Clemens Blouet points out, many people suffer from unsuccessful diets due to the special makeup of the nerve cells in the hypothalamus, a unique part of the brain that regulates metabolic processes within the body. The hypothalamus also functions to synthesize hormones and regulate basic physiological processes, such as thermoregulation, sexual desire, sleep, and the human need for food.
The hypothalamus contains a number of specific neuropeptides that participate in appetite regulation. If the voiced nerve cells "work", then a person experiences a feeling of hunger. If the neurons "sleep" - there is no appetite. This scheme is applicable to both humans and animals.
Scientists, thanks to their knowledge of genetic engineering, were able to turn off and on hypothalamic neurons in mice, after which they observed and drew certain conclusions. Temperature sensors, energy meters and other devices were implanted in the animals.
It was found that during periods of nutritional deficiency, neurons become active, which leads to the body adapting and performing its usual work, but with less energy expenditure.
In other words, if you severely limit your diet, it pushes the body to conserve energy resources, which, in turn, minimizes the effect of weight loss.
When scientists lifted the dietary restrictions, the animals' energy expenditure increased again.
Thus, experts have made an important conclusion: turning off hypothalamic neurons for just a couple of days leads to the activation of metabolic processes, which contributes to the loss of extra pounds.
Professor Blouet comments on this conclusion as follows: "We have managed to confirm that a number of nerve cells control appetite and energy expenditure of the body. Provided that sufficient food enters the body, these cells force a person to take this food, but if there is little food, they "switch on" the economy mode and slow down the process of burning fat."
One of the leaders of the experiment, Luke Bark, expressed confidence that this discovery will be useful for developing a new method of combating obesity. If you turn off the necessary nerve structures, you can change the settings of metabolic processes, targeting them for weight loss.