Known as "Water Fasting", the diet involves trying to lose weight by eating no food and only taking in the three beverages.
‘Water diet is the most dangerous weight loss regime ever. With water free and easily accessible, many have turned to the water diet for a quick weight loss fix.’
The trend has become popular on social media with thousands of people using the hashtag #waterfast to document their progress and encourage others to take part.
However, experts have warned it could be "the most dangerous diet ever" and said that it was taking the trend for cleansing "way too far", the Daily Mail reported.
Experts have likened Water Fasting to conditions like anorexia and said it should be avoided.
"It can be so bad for your organs. That's why people with anorexia can die of a heart attack. Their body feeds on their heart," Joanne Labiner, an eating disorder expert, was quoted by the Daily Mail late on Tuesday.
"Our body thinks it's an emergency and tries to prevent that fat storage from being used up, and it feeds on the muscle," Labiner added.
Water Fast has also created a buzz on microblogging site Twitter, where dieters claimed that the Water diet left their skin looking "amazing", while others claimed to have got the "best sleep of my life".
Conversely, a dieter, who lost 3 stone 9lbs, said that he was forced quit because he was so tired he could barely get out of bed.
A Toronto based kidney specialist, Jason Fung, suggested that water fasts were appropriate for clients who are obese or have Type 2 diabetes - but only under the supervision of a doctor.
"It can be done, people do them, but they have to be done safely," Fung said.
"I don't think it's the safest thing to do, but if you're obese, it's not the most dangerous thing, either. If you're relatively slender, it's more dangerous," he noted.