The term "Intermittent Fasting" (IF) has gained popularity in the media over the past few years as one of the most effective methods of losing weight. In 2016, Japanese biologist Ohsumi Yoshinori won the Nobel Prize for describing the mechanisms of autophagy, a natural process of regeneration and detoxification at the cellular level.
Since then, intermittent fasting has been adopted by many celebrities and bloggers as an effective method for losing extra pounds. According to this method, you do not need to limit yourself in meals, you just need to change the time intervals between meals.
It sounds great! But is it really so?
To start with, we'd like to remind you that the very principle of IG is that meals (the so-called food windows) alternate with periods when a person doesn't eat anything. There are different schemes: 16/8 (you can eat for 8 hours during the day, and for 16 hours, from evening until the next morning, you will have to starve), there are also 14/10, 20/4 schemes, and so on.
In his research, Ohsumi Yoshinori focused on autophagy using yeast fungi as an example, and some of his tests were conducted on mice. No humans were involved in his research. Moreover, the Nobel laureate has nothing to do with the IG methodology, as he confirmed at his lecture on January 17, 2020.
There is no scientific evidence that IF has any advantages over regular three meals a day in terms of its effect on the human body and those who want to lose weight. The whole thing is more about novelty and people's interest in another "miracle pill". One of the studies conducted by a team from the University of California, San Francisco confirmed this. The goal of their study, published in the JAMA Internal Medicine journal, was to determine whether a time-restricted eating pattern affects weight loss and metabolic health in overweight and obese patients.
The experiment involved 116 people (men and women from the United States aged 18 to 64 with a body mass index of 27 to 43), who were divided into two groups: with a regular meal schedule and a time-limited one, i.e., the IF group. The tests lasted 12 weeks. Thus, volunteers from the first group had to eat three times a day, at the same time (until 8:00 p.m.). The second group was forbidden to eat from 8:00 p.m. to 12:00 a.m. the next day, and during the eight-hour window (from 12:00 a.m. to 8:00 p.m.) they could eat whatever they wanted.
After three months, both groups of subjects did lose a little weight: about 900-1000 grams (minus 1.17%) with three meals a day and 600-700 grams (minus 0.75%) in case of IF. However, there were no serious changes in the indicators (% body fat, lean body mass (including organ, muscle, skeletal mass), fasting levels of insulin and hemoglobin).
However, the idea of associating hunger and autophagy did not arise out of nowhere. Research has shown that a cell recycles some of its components under artificially created nutrient deficiencies. Thanks to this mechanism, the cell continues to live under stress. However, what matters here is the level of stress: too much stress will cause premature aging of cells and the body! Therefore, the concept of "cellular starvation" is used in this research, and it has nothing to do with human fasting.
Autophagy happens almost every day in our body. As an example, our muscle fibers are destroyed during a workout, and then restored after a workout. The first and foremost rule: before switching over to any form of diet, you need to have good reasons for doing so, consult a doctor and get checked first!
So, the intermittent fasting popularity is a fashion influence on weight loss diets. There are no clinical studies on it. We definitely do not recommend using it in your entire life. You should focus on a healthy, nutritious diet, maintaining a balance between the energy you receive and the energy you spend. To live a full life, a person must receive all the nutrients in the recommended amounts with food: proteins, fats, carbohydrates, vitamins, and minerals.
Written by Petro Poliak, coach at Online Fitness Club.