Intermittent fasting is not superior to conventional caloric restriction diets

Intermittent fasting helps to lose weight and promotes health. However, scientists from the German Cancer Research Center (DKFZ) and the Heidelberg University Hospital have discovered in a study called HELENA – the largest survey to date on intermittent fasting Scientists conclude that there are many paths leading to a healthy weight. Everyone must find a diet that suits them best and then do it!

Eat eight hours then fast the next 16 hours? Or is it even better to fast two whole days a week, then eat without regret the rest of the week? Intermittent fasting, also known as 16: 8 diet or 5: 2 diet, is fashionable. Many popular self-help books on this subject promise weight loss without yo-yo effects, as well as sustained changes in metabolism and health benefits. The German Nutrition Society (DGE) warns that intermittent fasting is not suitable for long-term weight regulation. In addition, according to DGE, there is not enough scientific evidence on the long-term effects of this diet method.

"Until now, there are actually only a few smaller studies on intermittent fasting, but they have had remarkably positive effects on metabolic health," says Ruth Schübel of DKFZ. "It made us curious and we wanted to know if these effects could also be proven in a larger group of patients over a prolonged period of time."

In collaboration with a team of researchers and scientists from the DKFZ of the Heidelberg University Hospital, Schübel examined 150 participants in a study of overweight and obesity over a year as part of the study HELENA. At the start of the study, they were randomly categorized into three groups: one-third followed a conventional caloric restriction diet that reduced daily calorie intake by 20%. The second group followed a 5: 2 diet plan which also saved 20% of the caloric intake over the entire week. The control group did not follow any specific diet plan but was advised, like all the other participants, to follow a well-balanced diet, as recommended by the CEO. After the diet phase, the investigators documented the weight and health status of the participants for another 38 weeks.

The result can be as surprising as it is sobering for all the followers of intermittent fasting. HELENA researchers found that improvements in health status were the same with both dietary methods. "In participants of both groups, body weight and, with it, visceral fat, or unhealthy belly fat, were lost and the extra fat contained in the liver was reduced," Schübel reported.

Changes in body weight distribution among study participants were accurately determined with the help of a special MRT imagery made by Johanna Nattenmüller at Heidelberg University Hospital. . The good news is: a small diet success is already a big gain for health. Those who reduce their weight by only 5% lose about 20% of the dangerous visceral fat and more than a third of the liver fat – regardless of the dietary method used.

The investigators also found no difference between the two diet methods with respect to the other metabolic values ​​badyzed or the biomarkers and gene activities studied.

Although the HELENA study does not confirm the euphoric expectations placed on intermittent fasting, it also shows that this method is no less beneficial than conventional dieting. "In addition, for some people, it seems easier to be very disciplined two days instead of counting calories and limiting food every day," said Tilman Kühn, lead scientist of the trial. . "But in order to maintain the new body weight, people must also constantly adopt a balanced diet, in accordance with the recommendations of the GED," he added.

According to Kühn, the results of the study show that it is not primarily the dietary method that matters but that it is more important to choose a method and follow it. "The same evidence is also suggested in a recent study comparing diets low in carbohydrates and fats, that is, reducing carbohydrates compared to reducing fat intake while having a balanced diet." "said Kühn. In this study, participants also obtained comparable results with both methods.

The creed of scientists is: "Do it!" In any case, weight loss will be beneficial to the body and health, provided that it relies on a reliable diet method and a balanced diet.