Is it better to lose weight fast or lose weight slowly? meta-analysis

Is it better to lose weight fast or lose weight slowly?  meta-analysis

Many things are said about the speed of weight loss. For example, it is common to hear that losing weight too quickly is undesirable and that it can lead to negative effects, such as the popular “rebound effect”. It is true that the promise of losing weight quickly is something that usually accompanies fad diets, generally not recommended, but it is not convenient to deduce things from the exaggerations of those who want to sell us false miracles. The truth is that this type of affirmation about “fast weight loss” does not have much evidence, since the studies that exist on the subject are scarce and inconclusive, as I have already explained previously in this blog (one, of the).

In order to shed more light on this issue, a few weeks ago the first meta-analysis was published, which can shed some light on the situation. It is about “Effects of gradual weight loss v. rapid weight loss on body composition and RMR: a systematic review and meta-analysis” (2020) and its authors compiled the results of seven trials that compared “gradual” weight loss with another “quick”. From all this they were able to extract data and results related to a few parameters of interest: body weight, BMI, waist circumference, hip contour, body fat, percentage of body fat, lean mass, and energy expenditure at rest.

The work is quite concise in words, so getting to the point; These were the main conclusions of its authors:

“When weight loss of similar magnitude occurs, gradual weight loss was associated with greater decreases in body fat and body fat percentage, as well as greater maintenance of resting energy expenditure. However, the speed of loss weight was not associated with differences in lean mass, body weight, BMI, waist circumference, hip circumference, and waist-hip ratio.”

In other words, in the most well-known parameters with which weight loss is usually measured – body weight and BMI – speed had no significant effect. Even in the loss of lean mass, an aspect in which traditionally rapid weight loss tends to be less famous for causing greater loss of muscle mass (and which is usually counteracted quite effectively by increasing the percentage of proteins), no significant differences were found.

However, in other also interesting parameters, such as body fat loss (total and percentage) and energy expenditure at rest, gradual or slower weight loss achieved slightly better results. No big differences, but significant.

That is to say, it seems that losing weight more slowly does not present great advantages for weight loss in general, but it can help to do it a little more efficiently: focusing more on fat loss and perhaps allowing the metabolism to adapt a little better, since it presents a smaller reduction in energy expenditure that usually occurs in these processes, a phenomenon that can complicate the maintenance of lost weight. It should not be forgotten that this is the first meta-analysis published on the subject and that there are not too many studies included (some results were calculated with only four studies), but these conclusions can help us to anticipate where the shots could go on the matter. the rate of weight loss.

We will see if future studies confirm these results and if they manage to clarify some still doubtful issues, such as the loss of lean mass or the real existence of the famous and so often mentioned “rebound effect” after losing weight quickly, something that this meta-analysis does not analyze and that the studies carried out to date have not been able to confirm either (one, two). You can consult the previous post on this topic (one, two) to learn more about it.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Recent News

Editor's Pick