I am just saying that I tried this 5 day fast thing by accident last month and I really felt good
in fact I think I will do it again starting today - i put back on at least 5 of those pounds I lost
it was nice to bend over and not have that big inner tube squeeze across my stomach
you’re just losing water weight on these “5-10 day miracle diets”. your body stores glycogen in its muscles as a ready energy source. stored with this is water. when you ingest fewer calories than you burn per day, your body turns to these glycogen reserves first. as those are burned, the water is used. after a few days on a calorie deficit, your body will lose quite a bit of water weight... i’ve seen myself lose 7 lbs in 24 hours. that’s slightly less than a gallon of water. but it’s not real weight loss. as soon as you start eating at a calorie surplus again, you’ll restock those glycogen reserves and re-store that water.
this is why all of those miracle diets that the weight loss industry hawks are all predicated on losing 5-10-15lbs in the first two weeks. you can come up with endless permutations of diets and sell them to gullible consumers with this promise. but after two weeks, that stored water weight is gone and weight loss slows back to more realistic levels. by then, the hucksters have your money and instead of feeling like you’ve been duped, you blame yourself for failing because you saw your scale reading drop in the first two weeks, but now it has stalled. and then you go eat a box of twinkies to feel better and before you know it, you’ve gained back all of that weight (water weight) that you lost. this is yo-yo dieting and it is the foundation of the multi-billion dollar weight loss industry. they don’t actually want anyone to lose weight. they need repeat customers to afford their yearly vacations to St. Barts. ;)
weight loss is all about calories-in-and-calorie-out. burn more per day than you eat and your body makes up the deficit from your energy reserves (glycogen, fat, muscle). anything else (paleo, low-carb, atkins, etc.) is just a strategy for sticking to a calorie deficit.
http://ajcn.nutrition.org/content/56/1/292S.full.pdf