What actually left, over three days
Short fasts and broth-based resets show two to six pounds of weight loss over three days, on average. Roughly 70 to 80 percent of that is water, released as the body burns through stored liver and muscle glycogen, each gram of which is bound to several grams of water when it’s stored. Fat loss over the same three days runs between half a pound and a pound and a half. The two numbers get read as the same thing on a bathroom scale, and they are not the same thing at all.
Why it comes back on schedule
Glycogen refills as soon as normal eating resumes, and the water bound to it comes back with it. That process plays out over two to four days, which lines up almost exactly with when people report the scale creeping back up and start wondering what went wrong. Nothing went wrong. The body restored a fuel reserve it’s supposed to have, and the water that reserve carries came along for the ride, the same way it left.
That fat loss is smaller, and it behaves differently. That half-pound to pound and a half doesn’t return on its own. It stays off exactly as long as what you eat afterward keeps you at or below the calorie level that produced it, which has nothing to do with the cleanse and everything to do with the weeks that follow it.
What this means for how you should read three days
If the reason for doing this was to see a number drop, the number was always going to partially reverse, and knowing that in advance is better than discovering it a week later feeling like it undid something. If the reason was the other things a cleanse does, resetting eating patterns, giving you a clean baseline, a few days of eating simply, that value doesn’t evaporate when the water weight returns, because it was never stored on the same scale to begin with.
Three days was never long enough to produce durable fat loss on its own, and it was never supposed to be. The honest way to think about the scale afterward: some of what you’re seeing return is your body doing exactly what it should, and the part that matters more than the number was probably never on the scale in the first place.