CLAIM: 

Sitting in 40°C water can lead to 500g-3kg weight loss

FACT:

Medical experts say no evidence to support the claim

A YouTube video by a person identifying himself as Dr Biswaroop Roy Chowdhury claims that in a temperature of 40°C, if a person sits in water with the water level rising up to their chest, he can lose between 500 grams to 1 kilogram of weight within an hour. 

“In two to three hours, or whatever your weight loss goal may be, it will be achieved. You can lose two to three kilograms, especially if your weight has suddenly risen,” the influencer assures.

 The video has garnered 740,000 views and 216 comments, most of which attest to the claim being made.

What is the fact?

Dr Brendan Egan, an Associate Professor of Sport and Exercise Physiology at Dublin City University (DCU), described the claim as absurd.

Dr Egan cited the example of one of his studies to prove that sitting in water didn’t reduce weight. 

“We used the hot water immersion to induce sweating and loss of body weight through dehydration. So yes, we did induce weight loss of that magnitude in a shorter period but it was almost certainly all "water weight" and, all the weight was regained by the next day when the participants were rehydrated,” he told First Check in an email interview.

Dr Egan is the co-author of the study “Effect of rapid weight loss incorporating hot salt water immersion on changes in body mass, blood markers, and indices of performance in male mixed martial arts athletes”.

The DCU professor said their work “focussed on what we term rapid weight loss" in the context of combat sports.  

"There can't just be more and more weight loss because the sweat rate will slow down over time. Moreover it is probably unsafe to spend that much time in very hot water," Dr Egan said.

Dr M Ashraf Ganie, endocrinologist at the Sher-i-Kashmir Institute of Medical Sciences, a premier tertiary  healthcare institute in Kashmir, also said the claim is unfounded.

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