The clear liquid diet has been used advised by doctors in the medical field as a means to flush out your intestines prior to a colonoscopy and to treat stomach ailments, so yeah, it's both a miserable and highly dangerous diet to pursue for weight loss for an extended period of time.
The clear liquid diet is almost entirely comprised of sugar and water. "The goal of the clear liquid diet is to keep you hydrated, provide minerals and vitamins for energy and to keep your stomach and intestines rested," it says on Austin Diagnostic Clinic's site.
"It will not meet your nutritional needs and hence it is always recommended short-term only. This diet can also be safely recommended for patients with diabetes," it continued.
Here's what you can consume on a clear liquid diet, according to ADC:
• clear, fat-free broth
• plain Jell-O (Straight up gelatin)
• popsicles (no pulp or solids)
• apple and white cranberry juice (no pulp)
• lemonade (no pulp)
• clear sodas (not diet sodas)
• tea and coffee (with no milk or cream)
The clear liquid diet isn't safe to use for more than a few days, according to the Mayo Clinic. Besides being a diet to prep for medical testing, the clear liquid diet can be recommended as a short-term diet for digestive symptoms like vomiting and diarrhea — that's it.
There isn't even much warning on the internet regarding the dangers of pursuing a clear liquid diet for weight loss — probably because the internet assumes no one would even attempt it. But other liquid diets have proven dangerous, and the clear liquid diet may be the next logical extreme.
While the clear liquid diet can guarantee weight loss in just a few days, you'll likely gain the weight back when you start eating like a normal, functioning person again.