Can you lose weight by doing intermittent fasting?
Last reviewed: 12.03.2022
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Intermittent fasting will give the expected result if the period of hunger falls at night.
It has been proven by many experiments that a calorie deficit in the body is beneficial to a certain extent. It optimizes metabolic processes, facilitates cardiac function, stabilizes blood pressure, and increases physical performance. However, the types of fasting are different: the most famous are long-term water, dry and intermittent fasting. The latter option is considered the most benign and most easily tolerated by most people.
Studies show that the benefits of intermittent fasting are no less obvious than those of simply reducing calorie intake. Representatives of Columbia University found that such a beneficial effect is due to circadian rhythms. Scientists set up an experiment on insect flies - Drosophila, which are characterized by a change of 20-hour hungry periods with periods of prolonged saturation, lasting 28 hours. Insects that "adhered" to such a regime lived 13-18% longer than their relatives, who ate without intermittent starvation. In addition to an increase in life expectancy, other positive changes were noted: the flies were more active, they showed a slowdown in the signs of aging of the body. At the same time, the most pronounced effect was noted in “middle-aged” flies. Elderly flies, even with intermittent fasting, did not become long-lived, and in some insects the life span was even reduced.
If we consider the daily calorie content, then during the open access to food, the starving flies ate even more calories than the non-starving flies.
Scientists analyzed the dependence of these processes on circadian, or circadian, rhythms. Such rhythms are regulated by several genes, which, when turned off, would lose the beneficial effect of intermittent fasting. The benefit was also lost when the researchers shifted the diet by 12 hours. As a result, it was concluded that in order to lose weight and improve the condition of the body, the period of hunger should fall mainly at night.
The circadian rhythms influence many reactions and processes, in particular, autophagy. We are talking about intracellular cleansing, which renews the cell from the inside. This process is carried out mainly at night, during the rest of the body. When autophagy was suppressed in flies, the effect of intermittent fasting in them was reduced to “zero”. If this process, on the contrary, was activated, then Drosophila became long-lived, without even adhering to any fasting. Experts made another conclusion: autophagy depends on circadian rhythms, causing the effectiveness of starvation .
Like the studied insects, humans predominantly sleep at night. Therefore, the information obtained during the experiments can be used in relation to us. For example, intermittent fasting should involve a period of food restriction at night.
The full results of the work can be found on the pages of the journal Nature.