We often hear about celebrities losing weight over amazingly short periods of time thanks to the by-now all-too-popular cleansing diets. Some of us might even be tempted to try out one to see how it works and, no matter how difficult they may be to follow, we do it nonetheless. We should consider the effects they have on our health before plunging head first into them, nutritionists warn us, as a piece in USA Today reveals.

Cleansing diets are meant to help the body remove accumulated toxins but, at the end of the day, they’re no different from fasting, health experts say. They also imply depriving our body of proteins and other nutrients, which may impact our health in the long run in ways we might have never imagined. Last but not least, the efficiency of cleansing diets has never been proven in trials or studies, which would mean they are only a viable option over the short term.

“These kinds of diets are not a reasonable approach to weight loss, and there is no data that they do what they claim,” Gary Foster, director of the Center for Obesity Research and Education at Temple University in Philadelphia, shares for the aforementioned publication. The fact that one such diet has worked for singer Beyonce or actress Gwyneth Paltrow does not in any way mean that it will work for us too in real life, especially in the context in which these two stars only needed to lose a couple of pounds for a movie role, and they had to do it fast.

Joy Bauer, a registered dietitian in New York, agrees. Bauer upholds that cleansing diets mostly create only the illusion of losing weight, and this can be achieved with any type of fasting, so there is really nothing special about them. “People are always doing them, and it’s disheartening because they are sophisticated, smart people who know better, but they are so desperate for a quick fix. You don’t experience long-term success on them. You may be less bloated. You may feel lighter. You may be losing some weight, but much of it is water weight.” Bauer explains.

The Master Cleanse diet, which has reportedly helped Beyonce lose some weight for her part in “Dreamgirls,” has never been scientifically backed up, nutritionists also point out. It eliminates all solid food, and relies solely on drinking a mixture of fresh lemon juice, cayenne pepper, organic maple syrup and water, which makes it not that healthy either, experts conclude by saying.