list of fad diets that work fast

maybe this has happened to you: you invite a friend out to lunch, becausefrankly it’s been too long since you had a decent burrito, but they politely decline-- they say they’re on a cleanse. turns out they are consuming nothing but juicefor the next three days, because they want to give their digestive system a kind of hardreset. there are even juice cleanse or juice fastprograms out there, the basic idea is you pay a certain amount per day -- like sixtybucks -- and you’re provided with a set of juices to drink in a particular order. for the next few days -- usually 3, but sometimesup to 10 -- you eat no solid food. it’s

all juice, all the time, though the programsalso encourage you to drink water. if you’re lucky, you’re getting about 1200 caloriesa day -- and with some programs, much less than that. some people also choose to supplement theirfasts with laxatives and colonics, basically enemas. different programs promise different benefits,but most claim the same basic thing: that a cleanse will clear out your toxins and “reset”your digestive system. they’re also often considered a quick way to lose weight. except, none of these things are actuallybased on science.

so, let’s explore how juice cleanses supposedlywork, and compare that with we know about the human body. it’s rare to find a juice fast program thatexplains what they mean by toxins, or specifies what any of them are. but the generally accepteddefinition of toxin is that it’s a kind of poison produced biologically. and your body does produce harmful byproducts,like the ammonia that ends up in your urine. but that’s the thing -- it ends up in yoururine, because it’s filtered out, first by your liver and eventually your kidneys.your body has built-in mechanisms to get rid of the bad stuff.

drinking juice for a few days isn’t goingto make your liver or kidneys suddenly go into overdrive and clear out anything leftover. those organs are supposed to be constantlyworking -- if they aren’t, that’s what we call liver or kidney failure. these programs also tend to present anotherimage: that there’s all this extra gunk stuck to the sides of your intestines, andthe best way to get rid of it is to give yourself diarrhea for a few days, and then maybe finishthat off by flushing everything with water. but the human plumbing system doesn’t worklike the one you find in an old house. instead, waste is constantly moving througha healthy digestive system. there’s nothing

that’s still hanging out in your intestinesfrom that time you ate a handful of watermelon seeds when you were five, or even that doublecheeseburger you had last month. food normally takes 24-72 hours to be completelydigested, depending on what it’s made of and how often you have bowel movements. your body absorbs whatever it can, and therest comes out. it doesn’t get stuck to the walls along the way. but what about the weight loss? some of these programs do claim to help youlose weight. others emphasize that a cleanse should be for your health, not for weightloss, but also say that cleansing will do

things like “put you on a path to healthierhabits.” and people who do juice fasts do almost alwayslose weight, but most of it is in the form of water weight. but despite what it sounds like, this waterweight isn’t just the weight you lose from peeing out a bunch of water -- it actuallycomes from glycogen in your muscles glycogen is a form of stored sugar that yourbody uses when it’s running low on energy -- like when it’s getting way fewer caloriesthan usual, all in the form of juice. as soon as you start eating normally again,your body will replace those glycogen stores and you’ll bounce right back to whereveryou were.

on the other hand, for most healthy people,a juice fast probably won’t hurt them. they almost certainly won’t be getting all thecalories and nutrients they need, but most of these programs aren’t long enough todo lasting damage. so, if your friend wants to drink nothingbut juice for a few days, odds are they’ll be fine. but they aren’t detoxifying theirbody or rebooting their metabolism. they’re just … drinking a lot of usually very expensivejuice. thanks for watching this episode of scishow,which was brought to you by our patrons on patreon. if you want to help support thisshow, just go to patreon.com/scishow. and if you want to keep getting smarter with us,you can go to youtube.com/scishow and subscribe!

Tweet