Scientists: it’s impossible to lose weight on interval fasting

The popularity of the interval fasting method has increased in Russia over the last year. It is used to lose weight, improve metabolism, and regulate blood sugar levels. But is this method so good? Scientists from the United States have conducted their own study, which suggests otherwise.

Translate the conclusion and understand the scientific data “Championship” helped clinical psychologist, PhD and author of a book on intuitive eating Svetlana Bronnikova.

According to the results of the TREAT clinical trial, obese people do not lose weight on interval fasting, their metabolism does not improve, and their inflammation levels do not decrease. This method of nutrition leads to muscle loss.

Svetlana: These findings confirm that the human metabolism is a much more complex construct, and the introduction of innovative forms of nutrition should be treated with great caution.

What is the essence of the study?

The results of this experiment were published on September 28, 2020 on the website of the medical journal JAMA Network. This is the first human study in the history of science on the effects of interval fasting on weight loss.

Ethan Weiss, a cardiologist at the University of California, San Francisco, studied the effect of interval fasting on 116 volunteers who were stably overweight and diagnosed as obese. The average weight of the study participants was 100 kg. Part of the subjects practiced interval fasting and ate from 12 noon to 8 pm. The control group ate the usual three meals a day without time restrictions.

What were the results?

After 12 weeks, it was found that a slight weight loss occurred in both groups. The scientists do not attribute this effect to the type of diet: weight loss occurs when people start paying attention to what and how they eat, and in the case of the study participants, this is inevitable.

The group that practiced interval fasting showed no weight loss advantage over the control group. The study also found no differences in metabolic measures – the two groups showed no changes in insulin levels, glucose levels, activity levels or sleep quality, nor was there any reduction in inflammation in the body.

Moreover, the group of subjects who practiced interval fasting showed a significant loss of muscle mass (65% relative to total weight loss). With other forms of weight loss, this figure is usually no more than 20-30% of the total weight loss. And this is statistically associated with subsequent weight gain.

What did scientists say before this?

Interval fasting has been actively popularized over the past seven to eight years as a method of weight loss and control, rejuvenation, wellness, metabolic improvement (particularly controlling and reducing insulin levels in type 2 diabetes), and improving well-being and activity levels.

Research into the effects of time-restricted diets on mice began after a group of researchers led by Nobel laureate Yoshinoro Obuki of the University of Tokyo described the phenomenon of autophagy in yeast cells.

A team of biologists at the Salk Institute for Biological Studies in San Diego found that time-restricted diets led to weight loss in obese mice and improved their metabolic health, even when fed a diet high in sugars and fats. As a result, ideas about the health-promoting effects of interval fasting for humans have spread widely in popular culture.

Could interval fasting be dangerous to health?

A later study showed that the effects of interval fasting found in mice could not yet be extended to humans. The leader of the experiment, Dr. Ethan Weiss, who had been following interval fasting for seven years, stopped doing it the day he first saw his results. He told ABS-SBN News that he was shocked by the findings and that he considered prescribing such a diet to his patients a premature decision.

Weiss also emphasized the need for further research, especially on the safety of interval fasting for the elderly (60+) and people suffering from chronic health disorders such as type 2 diabetes.

Svetlana: I know, for example, that endocrinologists in Russia widely prescribe three or even two meals a day for type 2 diabetes patients, claiming that this stabilizes insulin. Unfortunately, these are potentially health-damaging practices with unpredictable effects.

A complete and balanced diet, the number of meals appropriate to a person’s needs and activity level, the absence of rigid rules and restrictions, and eating according to hunger and satiety signals, i.e. relying on the principles of intuitive eating, is still the most effective and scientifically proven method of staying healthy and not gaining weight in the long term.