Intermittent fasting, this food method adopted by Kourtney Kardashian, Jennifer Aniston or Chris Pratt, made many followers. Its principle is simple: eat on a limited time slot to help lose weight. However, it often happens that it does not work. A new study published in Annals of Internal Medicine By researchers from the Johns Hopkins University may well have identified why.
Does the time really count?
In this study, 41 volunteers aged 59 on average, with a BMI of 36, followed two different protocols for 12 weeks. A group had a 10 -hour food window from 8 a.m. to 6 p.m., consuming 80 % of its calories before 1 p.m. The other group ate between 8 a.m. and midnight, with more than half of the calories absorbed after 5 p.m. All have followed a balanced and identical diet, without ultra-transformed foods, with the same calorie intake.
At the end of the 12 weeks, the results are clear: the former lost an average of 2.3 kg, the second 2.6 kg. A difference too low to be significant. No particular improvement was noted on blood sugar, blood pressure or the waist. In short, the meal moment seems to weigh much less than the amount of food ingested.
The key factor is not time, but the calories
The main teaching of the study is due to a simple reality: eating less remains the decisive variable. For Nisa Maruthur, professor associated with the Johns Hopkins University and co-author of the study, “This makes us think that people who benefit from a restricted diet in time – and who manage to lose weight – it owes it more at the slightest amount of calories, than the shorter feed window“. Intermittent fasting can therefore help you slim down, not because you eat at certain times, but because it encourages you to eat less.