Welcome to my step-by-step, science based guide to water fasting that will show you how to do a water fast both safely and effectively.
My guide will take you by the hand and show you exactly how to prepare for a water fast, how much water you should drink while fasting, and how to end a water fast.
On top of this, I'll throw in a few advanced water fasting tips that'll help you maximize the health benefits of your next water fast.
Before dive in, here's a quick overview of everything you can expect to learn from my water fasting guide:
What is water fasting?
Dr Alan Goldhamer, the founder of TrueNorth Health Center in Santa Rosa, California (where thousands of patients have already experienced the health benefits of water fasting) says:
Fasting, by definition, is the complete absence of all substances except water in an environment of complete rest.
In other words, water fasting is a "diet" where you literally can't drink (or eat) anything else but pure water.
And of course, with your body getting in exactly zero calories, you can't expect to be able to do a lot of heavy work or intense exercise.
Now that you know what you're getting yourself into, let's take a look at what you need to do before you can start a water fast.
How to prepare for a water fast?
How important is it to properly prepare yourself for a water fast?
Well, it depends.
If you're one of those people who can eat to their heart's content one day, and then easily stay away from food the next day, you can simply do a water fast without any preparations.
But if you could end up stuffing your face with just about any fattening food you can get your hands on just a few days into your water fast, then you'd probably do yourself a favor by planning a smart transition into your next water fast.
If you take a little time to properly prepare for a water fast, this will skyrocket your chances of actually staying on the wagon.
So let's take a look at a couple of options on how to properly transition into your next water fast.
Get used to the idea of fasting before you even begin
A proper transition into a fully blown water fast can make the whole fasting experience way easier on you. Plus, it will greatly improve your odds of actually sticking to the fast for as long as you decide to.
So, as one of the first things you can do to prepare yourself for a water fast, is to start reducing the size of your meals before you even begin your fast.
You can take your time and gradually decrease your portion sizes in the weeks before you begin a water fast, but I suggest you do it for at least a couple of days before you start.
If you do this, both your mind and your stomach will already be better prepared to go completely without food once your fast begins.
Another thing you can do, is use intermittent fasting to make the transition into a full water fast easier on you.
How does that work?
It's simple. You could, for example, kick things off by not eating until 12:00 every day. As you get closer to your fast, you could start going without food till 16:00. After a few more days, you could fast until 19:00, and so on...
If you've never done a water fast before, this will give you an excellent insight into how things will go down once you start your water fast.
If, for example, you're having a really tough time staying away from food until 19:00, then you might want to give yourself some more adjustment time before diving into a full water fast.
I already have a couple of fasts under my belt, and I can tell you that a few weeks of intermittent fasting before the real thing can be a real game changer.
Once you get fully comfortable with the idea of not eating until 19:00, your mind and your stomach will be almost fully prepared to go completely without food.
Now, let's take a look at a pretty stubborn myth in the water fasting community.
Do you need a colon cleanse before a water fast?
One of the first things people learn in the water fasting community, is that you need to do a colon cleanse before starting your water fast. Or at least, that you need to do a colon cleanse after you've already fasted for a couple of days.
This idea is based on a very old theory of autointoxication. Physicians in ancient Egypt believed that stools should not stay stuck in your digestive system for too long, or the bacteria in your colon will start producing toxins from them.
During a water fast, those unknown toxins could be absorbed into your bloodstream, which could supposedly poison or "disease" your body.
Modern science, on the other hand, has found no evidence that supports this outdated theory of autointoxication.
The only thing that's actually been proven, are the health complications that were brought on by many different colon cleansing procedures on the market today.
Other side effects include nausea, diarrhea, and nervous disturbances.
Since no evidence supports the idea of having to do a colon cleanse before or during a water fast (while plenty of evidence exists that colon cleansing procedures can be dangerous) I would definitely advise against cleansing your colon before or during a water fast.
On top of that, I personally read through dozens of scientific studies on water fasting, and none of them used colon cleansing before or during the fasts. Not a single person in those studies suffered from autointoxication, self-poisoning, or any other disease.
If the medical professionals who conducted those studies felt a colon cleanse is unnecessary for water fasting, then that's good enough for me.
In other words, as far as modern science is concerned, you can start a water fast without any special preparations or invasive colon cleansing procedures.
Time to take a look at how to actually do a water fast.
How to do a water fast safely and effectively
In this part of my water fasting guide, I'll tell you all about how to do a water fast correctly.
Water fasting isn't exactly rocket science, because there's literally just one major rule you need to remember:
Don't eat or drink anything else but pure water.
While you could get away with some other stuff without breaking the fast, your fast couldn't be called a pure water fast anymore.
Let's kick things off with how much water you need to drink every day during a water fast.
How much water should you drink on a water fast?
The officially recommended water intake for adult men stands at about 3 liters (13 cups) of water per day. Women, on the other hand, should drink about 2.5 liters (11 cups) of water every day.
Since you won't be eating or drinking anything else during a fast, you can't go wrong if you just stick with the recommended daily water intake.
The easiest way for you to tackle this is to pre-fill the bottles with the daily amount of water every morning.
If you fill three 1-liter (33.8 fl oz) bottles and place them on your kitchen counter, they will serve as a nice visual reminder of how much water you have to get through by the end of each day.
Oh, and don't drink too much water at once. I know this is common sense to 99% of people, but you'd be surprised...
Just try to drink down all the water slowly and evenly throughout the day.
Personally, I don't think we really need to drink that much water during a water fast, mostly because we won't be eating any dry/dehydrating foods during the fast.
In words of one of my precious reader, drinking the recommended daily amount of water will make you "piss like a racehorse". But who am I to go against the official recommendations (oh, my).
Now, let's take a look at another unpleasant thing that can catch you off guard during a water fast (but it won't surprise you, because you have this guide).
Avoid feeling lightheaded/dizzy during a water fast
Water fasting has been proven to cause something called "orthostatic hypotension", which is a temporary drop of your blood pressure that can happen if you stand up too quickly.
This won't start happening before you reach full ketosis (so at least 2-3 days into a fast), but even then, a lot of people never run into this issue.
Like I said, you can completely avoid this problem if you're simply careful about getting up slowly. But just in case you do get caught by surprise, here's what you need to do:
If you just stood up too fast from a sitting or lying position, and suddenly felt lightheaded or even dizzy, you need to bring your head back down as quickly as possible.
Either immediately sit or lie back down, or just bring your head down by bending forward. With your head down, hold onto your knees for a second or two, and everything should return to normal. You're ready to (slowly) stand up again.
What's the absolute worst thing that could happen? In a highly unlikely scenario, if you really sprung up on your feet from a lying position with full force, you could lose consciousness for a few seconds, and possibly hurt yourself as you fell to the ground.
The bottom line is, just take it easy when you're getting up and you should be alright.
How long can you safely water fast for?
If you're completely new to water fasting, I'd say your first water fast shouldn't be longer than 3 days (or 72 hours).
But even with some fasting experience under your belt, people in the water fasting community agree that if you're going to do a water fast longer than three days, it's best to check in to a fasting retreat and do the fast under medical supervision.
And I couldn't agree more. A fasting retreat can make the whole experience of fasting indescribably easier on you, because 1.) countless distractions and temptations of your everyday life simply don't exist, 2.) you're surrounded by likeminded people who are also interested in fasting, and 3.) you have a medical professional that can answer any of your questions handy at all times.
The only downside to a fasting retreat is, not everyone can afford the price and/or to leave their own lives behind for a week or two.
No matter how long you ultimately decide to fast for, always be mindful of any warning signs. It's normal to feel a bit weaker than usual, to feel lightheaded when getting up, or even run into some temporary heart palpitations during a water fast.
But as soon as something starts feeling too extreme, do yourself a favor and end the fast by following the instructions below.
How to properly end a water fast?
Because you won't be eating any solid food during your water fast, your digestion might not be ready to handle your normal diet right off the bat.
Eating too much, especially of the hard to digest foods right after you end a water fast could cause some unpleasant issues.
Here's a list of foods you can easily follow to properly end a water fast and avoid any potential complications along the way.
A list of foods to break your water fast with
- fruit juices
- vegetable juices
- raw fruits
- raw leafy green vegetables (lettuce, spinach...)
- vegetable soups
- cooked vegetables (potatoes, rice...)
- raw vegetables (celery, carrots...)
- cooked grains and beans
- milk, dairy, eggs
- fish, meat
- everything else
The foods on this list are already sorted according to how tough they will be to digest. The easily digestible foods are on top of the list, while the hard-to-digest ones are at the bottom.
At the end of your water fast, you can simply start with the foods at the top of the list and slowly make your way down. With every meal, you can include more and more foods from the list.
EXAMPLE: Break the water fast with some orange juice (food group #1). Eat a banana (food group #3) a few hours later. If everything feels ok, you can make a small salad with yoghurt topping (food groups #4 and #5) as your next meal. And so on...
Just make sure to end your fast with small meals, spaced at least two hours apart. As you include more and more foods from the list, you can also start slowly increasing the size of your meals.
What can happen if you ignore the food list?
In one recorded case, a "professional faster" ended a 30-day water fast with fruit, one of the most easily digestible foods on the planet. But because he ate a little bit too much, he had to deal with some pretty severe stomach pains and cramping for a while.
Now, 30 days is a LONG water fast, and I strongly advise against ever fasting for 30 days in one go (unless you have a ton of fasting experience and you're doing a supervised fast).
If you fasted for "just" a couple of days, it's highly unlikely you'll run into any trouble as you end your fast. In fact, you'll probably be able to return to your old diet right off the bat. But if you fasted for a week or more, you'll need to slowly transition back into your normal diet.
The general rule is, the longer you fasted, the more careful you need to be about how you break the fast. But no matter how short you water fast was, you simply can't go wrong if you take some time to ease back into your normal diet.
Depending on how long you fasted, it could take anywhere from 1-4 days for your digestion to get up to 100% again.
The bottom line is, most people won't need to follow the food list to the letter. It's ok to skip a step or two as you go through it, but it can never hurt to keep it in mind as a general guideline.
Now that you know how to actually do a water fast, we can take a look at some of the most important benefits of water fasting.
The science-proven benefits of water fasting
If you're like most people, then the single most important benefit of water fasting to you is probably weight loss.
But what many people don't know is that modern science has discovered water fasting can literally "kill" your hunger and cravings (you'll see the science on this in a bit).
And the third, by far the most amazing benefit of water fasting would be its potential to treat cancer, something that science is only starting to take a closer look at.
Without further ado, let's look at the single most popular benefit of water fasting, weight loss.
How much weight can you actually lose with water fasting?
Yes, weight loss is easily the most common reason why people look into water fasting in the first place.
Because it's true, water fasting IS one of the fastest weight loss methods in existence. I, for one, have personally proven it's possible to lose almost 3 pounds per day (or almost 15 pounds in 5 days) with water fasting.
So, if you don't really care about much about how much weight you will lose during your next water fast (or how to boost your weight loss results even further), then all you need to do is follow the instructions you've gotten so far.
But if you are interested in the science that will skyrocket your fat burn rate, protect your lean body mass, and show you the exact steps I took to lose almost 3 pounds a day, then you'll love to read the weight loss section of this guide.
And while it's true that my own water fasting experiment was a bit extreme (I really did a lot of stuff to boost my water fasting results even further), you can definitely count on losing at least a pound or two per day.
On to the next amazing benefit of water fasting, a severe reduction or even complete disappearance of hunger and cravings.
Disappearance of hunger and cravings
If you're looking into water fasting to get rid of a couple of pounds, but you're thinking there's no way you could go completely without food, here's some surprising science for you:
In a study, where a group of people fasted for two weeks, they proved that hunger and cravings almost completely disappear during the water fast.
In another water fasting study, where people fasted for as long as 117! days, scientists also confirmed that "hunger was virtually absent".
From my personal experience with water fasting, I can tell you that as long as you can get through that first awkward phase (the first day or so), cravings and hunger DO become way easier to handle. During one of my fasts, I literally felt like I no longer care about food at all.
And while water fasting definitely isn't a walk in the park, it can actually be easier to handle than some of the less restrictive diets. While any diet (that actually allows you to eat food) might seem easier in comparison to water fasting, the hunger and cravings might actually be tougher to handle with a little food than with no food at all.
On to the next amazing benefit of water fasting.
Can water fasting really heal cancer?
If you've been a part of the water fasting community for a while, you've probably heard of a few miraculous cancer recovery stories. Personally, I've read about "terminal" cases (as diagnosed by modern medicine), who made a full recovery just because they lived off nothing but water for a few weeks.
First of all, I have no way of knowing whether or not any of those stories are true. Second, I'm not a qualified medical professional. So, if you've been diagnosed with cancer, make sure to discuss any water fasting options with your own doctor.
With that out of the way, here's some science that proves water fasting could actually be effective for cancer treatment:
In one study, they discovered that water fasting can be as effective as chemotherapy drugs in delaying tumor growth and that it can increase the effectiveness of chemotherapy drugs in certain types of cancers.
Another piece of research looked at cancer patients who fasted for different amounts of time before and after chemotherapy. Fasting was able to reduce or in some cases completely eliminate the negative side effects of chemotherapy (fatigue, weakness, hair loss, headaches, nausea, vomiting, diarrhea, numbness, tingling...)
While a lot more research needs to be done before the final verdict on treating cancer with water fasting can be reached, the current evidence certainly suggests water fasting could potentially replace, or at least boost the effectiveness of certain chemotherapy drugs in cancer treatment.
Time to take a closer look at water fasting and weight loss.
In this part of the guide, I'll show you exactly what I did to lose 14.6 pounds (6.6 kilograms) in 5 short days.
This comes down to losing almost 3 pounds (1.5 kilograms) per day, which is insanely quick by any standard.
And just in case you're wondering, the answer is no. It's damn near possible to lose 3 pounds of pure body fat per day.
Read this part of the guide all the way through and you’ll understand exactly what happens behind the scenes of such an awesome drop of that number on your bathroom scale.
HINT: There's actually SIX different types of body weight you'll end up losing when you lose weight this quickly with water fasting (I'll cover all of them in a bit.)
I'll also show you some advanced weight loss tricks that you can use to boost your water fasting results even further.
These tips won't "only" help you laser-target that stubborn body fat, they will also help reverse the loss of muscle mass during a water fast.
Before we dive in, you should know that this advanced guide focuses on maximizing your weight loss results during water fasting.
In other words, I'm assuming you already have some experience with water fasting or that you at least understand how water fasting is done.
Now that you know what you're getting yourself into, here's a short roadmap you can use to easily navigate this advanced guide to water fasting for weight loss:
Muscle loss during water fasting (and how to reverse it)
This is easily the single most important issue of water fasting for weight loss, so I'll talk about this first.
In one study, scientists proved that it's possible to destroy as much as 13 pounds (5.9 kilograms) of lean body mass during a 21-day water fast.
(Your lean body mass includes everything in your body that's not body fat...so muscle mass, bone mass, water weight, glycogen, internal organs, etc.)
Now, maybe youre the kind of person who doesn't really care about how much muscle mass you will lose during a water fast. Maybe you just want to get rid of that stubborn and annoying body fat as quickly as possible.
But even if that's you, you should know that the single most important muscle in your body that can suffer because of this (and that muscle just happens to be your most important vital organ as well) is your heart.
Relax. A short water fast isn't likely to cause any serious damage your heart. I'm only telling you about this scary stuff to make sure you always stay on the safe side with fasting.
But still. If you ask me, losing even a single pound of muscle mass mass as you go after a quick drop of that number on your scale isn't really worth it.
Especially since science has already discovered a better and more effective way of fasting. This modern way of fasting has actually been proven to be a lot safer than water fasting in over 10,000 of medically-supervised cases.
The kind of fasting that can fully reverse the unnecessary destruction of your muscle mass and vital organ tissue is called muscle sparing fasting.
And the best part? When done right, muscle sparing fasting won't slow down the incredibly fast fat burn water fasting can deliver.
In fact, modern science has proven that muscle sparing fasting can be done in a way that doesn't interrupt the fasting ketosis in your body. When done right, muscle sparing fasting can actually offer higher fat burn rates than water fasting alone ever could.
But I'm getting off track here. This isn't a guide on muscle sparing fasting, but a guide on how to maximize your water fasting weight loss results. So let's get on with that.
The ugly truth behind my awesome water fasting results
In this part of the guide, I'll explain all about the SIX different types of weight that you will lose during a water fast.
(I've already covered the loss of muscle mass during water fasting, so that leaves us with 5 more.)
After you're done with this part of the guide, you'll understand what actually goes on when you lose weight as quickly as with water fasting.
You'll see exactly why most people keep celebrating that quick drop of that number on their bathroom scale...only to end up totally frustrated after they quickly regain all the lost weight.
To be fair, "fake" weight loss results aren't just a problem of water fasting. Most quick weight loss diets on the market today take advantage of this as well.
Now, let's dive right into taking a closer look at what actually goes on "under the hood" of extremely fast weight loss results.
If I had to name the single most widespread, yet totally irrational fear of weight gains, then drinking water would definitely be it.
So let me set the record straight once and for all:
Drinking plenty of water DOES NOT make you gain weight.
So even though water fasting is about driniking lots of water, this will actually help you get rid of some of the extra water weight that's normally "stuck" on your body.
Whatever your fears about water fasting might be, you shouldn't be afraid to drink plenty of water throughout your fast.
In fact, drinking pleny of water throughout your next water fast will only help keep your body properly hydrated and keep your metabolism properly revved up.
(If you're interested in exactly how much water you need to drink during a water fast to maximize your weight loss results, you can check out my general guide on how to actually do a water fast.)
So let's take a closer look at some of the reasons why your body actually holds on to unnecessary water weight (and how water fasting can help you get rid of that extra water weight).
While your body stores away most of the energy in your body fat reserves, it also stores some energy in your muscles and your liver as glycogen.
And just like your body fat, your glycogen reserves (plus the water bound to them) can add quite a few extra pounds to your total body weight.
I can't cover all the details on how much extra weight you're carrying around because of glycogen or how to get rid of it in this guide on wight loss with water fasting.
(But you can read all about the benefits of getting rid of all the glycogen in your body in my science-based guide to glycogen and weight loss.)
But when it comes to how glycogen affects your water fasting weight loss results (and your energy leves during fasting), you need to understand what will happen during the first 3-5 days of your next water fast:
- Your body will burn through most of your glycogen reserves, meaning that you can lose as much as 10 pounds (5 kilograms) of glycogen-bound water weight. Again, this will make your final water fasting weight loss results look pretty damn awesome, but this doesn't mean you're actually losing any extra body fat.
- After your body wipes out your glycogen reserves, you will start feeling a lot weaker and possibly even dizzy (find out how to deal with this in my general guide to water fasting). Like I said, glycogen is how your body stores energy, and with your glycogen reserves wiped out, you simply won't have as much spring in your step.
- You won't be able to reach your highest possible fat burn rate for as long as your body can still rely on glycogen for energy. So unless you follow the tips I'm going to reveal later on in the guide, you'll have to wait for 3-5 days before your body gets rid of glycogen at its own natural pace.
On to another type of weight you'll almost inevitably lose during water fasting.
Sodium is a very common mineral in our diets (think table salt) and unless you're sticking to a specific, low-sodium diet, you're probably packing on quite a lot of extra pounds because of sodium (salt).
You see, just like glycogen, sodium too binds water to itself. So the more sodium you eat, the more sodium-bound water weight you might be carrying with you at all times.
Again, I can't cover all of the details on sodium and water weight in this guide to water fasting and weight loss.
(But if you want to see just how much extra weight we're talking about, you can take a look at my personal experiment with sodium and weight loss.)
The important thing to remember about sodium and water fasting is this:
Because water fasting means that you'll basically be getting in zero sodium, your body will finally get the chance to flush any extra sodium out of your body.
In other words, if you switch from a high-sodium diet (aka your standard modern diet) to water fasting, you'll quickly drop up to 4 pounds (2 kilograms) of sodium-bound water weight.
Again, this will make your final water fasting results look a lot better on paper, but it won't actually help you burn off any of that annoying body fat.
Time to take a look at another reason why your weight loss results after a water fast may be "inflated".
If you're on just about any kind of a diet (where you're actually allowed to eat solid food), you'll always be carrying around a few pounds of partially digested food in your digestive tract.
But after you stop eating solid foods completely during a water fast, your colon will still keep emptying out for a few days into your fast.
In fact, some people even do a colon cleanse before or during a water fast - to help speed up this process and help the body get rid of "toxins".
(If you're one of those people who'd actually consider doing a colon cleanse for a water fast, then you should definitely read what science has to say about this in my science-based guide to colon cleansing and weight loss.)
Ultimately, with or without a colon cleanse, your weight may drop by a few pounds because at least some of the digested food will leave your body during a water fast.
In other words, this means that you can lose as much as 7 pounds (3 kilograms) of non-fat weight during your next water fast, just because your colon will empty out a bit more than usual.
So let's wrap up this part of the guide with what should be the ultimate target of any well-designed diet, your body fat.
If you've read all about the FIVE types of weight loss results that have absolutely nothing to do with your body fat, then you might feel like you'll barely lose any body fat at all during a water fast.
But I can assure you that water fasting IS one of the fastest ways in existence for you to get rid of that annoying body fat.
Water fasting is definitely not without problems, but that doesn't mean your body fat won't melt away like it's on fire during a water fast.
Explaining (in words) how much actual body fat you can expect to lose during a water fast would be quite tough, because it depends on a lot of factors (your starting weight and body composition, for example).
So in order to help you understand just how much body fat you can expect to lose, I'd need to hire a coder and develop a water fasting calculator.
Such a calculator would be able to tell you as precisely as possible how much total body weight, how much body fat and how much muscle mass you can expect to lose.
But for the time being, I can "only" offer you some science that will help you estimate how much total weight you can expect to lose during your next water fast.
Estimate your own water fasting results
While I lost almost 3 pounds per day in my own water fasting weight loss challenge, you could be getting better or worse results than me.
Your final water fasting results will depend on a lot of factors, but mostly on how much weight you have to lose at the beginning of your fast.
While a skinny, 140-pound guy can't expect to lose anywhere near 3 lbs per day, a heavy, 300-pound guy could lose even more weight than that.
So the more weight you have to lose at the beginning of a fast (and the longer you plan on fasting), the better your final weight loss results will be.
Because my own results may not be a good rule of thumb for everyone, I turned to science to help you estimate what kind of results you can expect to get with a typical water fast.
According to one study  that compared the average weight loss results between men and women, men can expect to lose more weight than women during water fasting.
I've converted the data from the study into a pretty long table.
But you can easily use this table to estimate your own results depending on how long your fast is going to be and your current weight.
|Water Fast Duration (days)||Weight loss - women (%)||Weight loss - men (%)|
Here are two example calculations:
Example 1 (for women):
You're a 150-lbs woman who plans on doing a 7-day water fast. You can estimate your weight loss results by taking the value from the second column in the table for a 7-day water fast and multiply it by your current weight.
Your estimated 7-day water fasting results: 150 lbs * 4.5 / 100 = 6.75 lbs
Example 2 (for men):
You're a 180-lbs man who plans on doing a 14-day water fast. You can estimate your weight loss results by taking the value from the third column in the table for a 14-day water fast and multiply it by your current weight.
Your estimated 14-day water fasting results: 180 lbs * 7.9 / 100 = 14.2 lbs
But enough about estimating your water fasting weight loss results.
Let's get on with some of the more advanced water fasting tips that are bound to skyrocket fat loss during your next water fast.
How to speed up fat loss BEFORE a water fast
Before we get to my advanced water fasting weight loss tips, let me repeat this one simple fact:
Water fasting IS one of the fastest ways to lose weight on the planet.
In other words, your final weight loss results will beat the results of 95% of all diet and exercise programs in existence.
That's even if you do absolutely nothing but lie in bed all day.
With that out of the way, here are a couple weight loss tips you can use to boost your water fasting weight loss results before you even begin the fast:
Enter into fasting ketosis 3-5 days sooner
If you simply eat less calories than usual before your water fast, your body will need to burn through a lot less energy reserves in your body before it can laser-target your body fat reserves.
This means that you can start burning off that stubborn body fat at the highest possible speeds a lot sooner than if you simply waited things out.
In other words, eating less calories before your fast can help you enter a state of ultra-high fat burn called "water fasting ketosis" 3-5 days faster.
But restricting calories right before your fast isn't the only thing that can help you start enjoying that state of super-high fat burn as quickly as possible.
Do this BEFORE the fast to speed up fat loss DURING the fast
Exercising right before a water fast is another awesome tip that will help you reach that highly sought-after state of extreme fat burn 3-5 days faster.
Because exercise also helps you wipe out the energy reserves in your body that prevent you from being able to really laser-target that ugly body fat.
So you can simply eat less, you can rely on exercise, or use a combination of both to enter water fasting ketosis as early into your fast as possible.
On to the water fasting weight loss tip that can be used by those who aren't fans of eating less or exercising.
Burn off more body fat without eating less or exercising
The third tip you can use right before a water fast (to speed up your entry into water fasting ketosis), is to stick with "ketogenic" meals.
Again, ketogenic meals can help you start burning off your own body fat reserves at a high rate (without necessarily eating any less calories or exercising).
So before a water fast, you can use any combination of calorie restriction, exercise, or ketogenic meals to be able to reach your highest possible fat burn rate up to 5 days faster.
Let's move on to the water fasting weight loss tips you can use during the fast.
How to speed up weight loss DURING a water fast
Back when I did my water fasting experiment, I didn't really know a lot of science on how to speed up weight loss during a water fast even further.
But I've done my research since then. So what you're about to see, are some pretty neat tricks that can boost your fat loss even beyond what water fasting can do on its own.
In other words, even though I've gotten some pretty amazing results with my experiment, if I had used any of the tricks you're about to read, I could have lost even more weight during my water fast.
Let's dive right in.
Use caffeine to DOUBLE the release of body fat
If you really want to skyrocket your fat burn rate during your next water fast, here's a science-based weight loss tip that can help you out:
Research has proven that taking just a tiny amount of caffeine, an extremely popular natural fat burner found mostly in coffee and tea, can literally double the release of fat from your body fat reserves.
(To find out more about how caffeine actually speeds up fat loss, how many calories it can actually help you burn, and how to make caffeine work on ANY diet, go to my science based guide to maximizing your weight loss results with caffeine.)
In other words, if you do a water fast without caffeine, your highest possible fat burn rate will be limited by your body's natural ability to release fat from your body fat reserves.
But if you take caffeine during a water fast, you can actually reach a state of "superhuman" fat burn (because caffeine helps your body release and burn off that stubborn body fat even faster).
Also, because caffeine will help you release more energy from your body fat reserves, you'll feel much more energized and mentally focused during a water fast.
Time to take a look at an awesome drink that's also been scientifically proven to speed up weight loss:
Drink green tea to burn more body fat
Yes, green tea is another zero-calorie drink you can use to speed up weight loss during a water fast.
Science has proven that green tea can speed up fat burn by over 35%!
And the best part?
Burning off more body fat also means you'll destroy less of your lean body mass (because your body will be able to draw more energy from those ugly body fat reserves).
The ability of green tea to protect your lean body mass while helping you burn away more body fat during a water fast is amazing in and of itself.
(But if you want to discover a few more little-known weight loss benefits of green tea, you can read all about them in my science based guide to boosting weight loss with green tea.)
Here's another kind of tea you can drink for quicker fat loss during a water fast:
Drink oolong tea to burn more calories
What if I told you, or better yet, what if I could prove to you that burning off even more calories during a water fast comes down to something as simple and natural as drinking tea?
Well, science says, oolong tea contains the so called "polyphenols" that have been proven to speed up weight loss.
Furthermore, teas like oolong tea also contain caffeine, and you've already seen the science on how well that one works.
Needless to say, the fat burning combo of polyphenols and caffeine you can get in by drinking some oolong tea, could easily boost your final water fating weight loss results even further.
(If you want to find out how many calories oolong tea can help you burn, how it can help you better target your body fat, and discover a little-known weight loss benefit of oolong tea, then you can go to my science based guide to speeding up weight loss with oolong tea.)
But now it's time you find out how to avoid one of the most common traps people who are doing a water fast for weight loss tend to fall into.
How NOT to speed up weight loss during a water fast
I really need to warn you about one of the stupidest mistakes I made in my extreme water fasting challenge. I did it, because I simply didn't know about this back when I went through with my weight loss challenge.
My dumb mistake was, I tried to boost my water fasting results with exercise.
I mean, it's widely known that exercise and weight loss go hand in hand, right?
So why not do some light exercise to boost your water fasting results, especially once you start feeling that "energy high" after a couple of days?
Well, unfortunately for me (but fortunately for you cause you're reading this now) it took me quite a while before I found out just how dangerous exercise can be during a water fast.
One water fasting study proved that every hour of exercise during a water fast will destroy over 100 grams of your lean body mass!
And the people in the study weren't doing intense exercise. The loss of lean body mass is bound to happen even if you exercise lightly during your water fast.
Like I said, that destruction of your lean body mass will not only hurt your muscles, it can damage your vital organs as well.
The bottom line is, you can do pretty much everything you normally do during a water fast.
Just do your best to avoid any activities that will raise your heart rate, make you start breathing heavily, or require a lot of energy to perform (think heavy work, weight lifting, or basically any kind of sport).
And while this wasn't exactly a tip that can boost your water fasting results, it's even more important you understand what you're NOT supposed to do.
So many people make the mistake of staying overly active during a fast, but instead of improving their final water fasting results, they only end up harming their bodies.
How to prevent weight gain AFTER a water fast?
That very first bite you take after not eating for 5 days will taste out of this world. Even if you start by eating a food you're usually not all that excited about (celery, anyone?), that first sensation of food in your mouth will be far beyond your usual experience.
If you haven't been eating for five days, you need to slowly ease back into your normal diet. This is even more important with longer fasts. But even after a 5-day water fast, you can't just start eating like a horse right away.
You can start by eating some fruit every couple of hours. After a while, you can start including some smaller meals.
Your stomach will shrink during the fast and you'll be excited to notice you now feel fully satisfied with far less food than before the fast.
You want to hold on to that feeling for as long as possible, so try not to expand your stomach too quickly with huge meals.
The daily breakdown of my water fasting weight loss experiment
Here's exactly what happened during the 5 days of my extreme water fasting weight loss experiment.
If you're thinking of doing a water fast yourself (even if just for a day or two), this will give you a better idea of what to expect.
You'll also see that I've gotten myself into a pretty risky situation on the fifth day (and had no choice but to "cheat" during my fast).
Let this incident be a reminder to you that water fasting is not to be taken lightly (especially if you plan on exercising during your fast), and that safety must always come first.
Day 1 (daily weight loss = 3.1 lbs / 1.4 kg)
During the first day of the fast, my energy levels were still pretty good. I spent about two hours on my bicycle, plus, I did some sprinting. By the end of the day, I felt really tired, but nothing too out of the ordinary.
The hardest part of the first day is handling your hunger and food cravings.
I properly transitioned into my water fast, so my body was already used to getting just one meal per day (a late dinner). Because I was tired from exercising without food, I fell asleep way before dinnertime. So during the first day, I tricked my mind into not even noticing that I was going to skip food altogether.
But that only got me through the first day.
Day 2 (daily weight loss = 2.4 lbs / 1.1 kg)
The hunger, the cravings, and the constant feeling of emptiness in your stomach. Even without exercise, these things CAN get to you.
On the second day of my water fast, I went on a hike. But after about two hours of brisk walking, that was it. I was completely out of gas, and that familiar feeling of dizziness started creeping in.
A little dizziness is completely normal during a water fast (even if you completely avoid exercise). But during my previous fasts, it never started feeling dizzy before day three.
Exercise really worked to speed things up.
Day 3 (daily weight loss = 3.1 lbs / 1.4 kg)
The third day could easily compete for the worst day of my life.
I was so completely out of energy, that I barely dragged myself around the apartment. The only time I felt this way was when I was extremely weak because of an illness.
If you do a water fast without exercise, the third day is usually much, much easier.
So if you want to burn off more body fat by exercising in the beginning of your water fast, feeling like crap might be the price you'll have to pay.
The good news was, my hunger was almost completely gone by the third day.
Day 4 (daily weight loss = 3.7 lbs / 1.7 kg)
On the fourth day, I got some of my energy back.
I was actually able to walk a couple of miles, but that was it for the day.
Like I said, the hunger was now completely gone. I literally felt like I didn't care if I ever eat anything again.
And this is actually the biggest advantage of doing a water fast for weight loss.
If you can learn how to handle yourself during those first few days, you'll get to a place where hunger virtually disappears.
But it wasn't until the final day that I got reminded fasting is no walk in the park.
Day 5 (daily weight loss = 2.2 lbs / 1.0 kg)
The last day of my water fast surprisingly began really great. I felt like I had a TON of energy, so I courageously went on a hike.
But almost exactly at the farthest point from my home, I nearly collapsed from exhaustion.
I remember leaning against a fence, just wanting to lie down. I had no idea how I was supposed to get home.
I had no choice. My safety had to come first, even if it meant not completing my weight loss experiment.
Somehow, I managed to slowly make my way to the nearby store, and bought some dates.
Dates have an extremely high-glycemic index, which means that the sugar they contain will rush into your bloodstream like a speed train.
And boy, did they work.
I only ate two dates, and it was like pouring gasoline on fire. With this quick energy boost, I was able to get back home with no problems.
So yes, I technically "broke" the fast before day 5 was over.
But those two dates weighed only a couple of grams, so they really couldn't have affected the final weight loss results a lot.
So in spite of me "cheating" during my fast, I still ended up losing 14.5 pounds (6.6 kilograms) in 5 short days.
How much body fat did I actually lose?
Like I said, my water fasting weight loss results look pretty impressive on paper:
I lost a total of 14.6 pounds (6.6 kilograms) in less than a week, while the recommended weight loss rate is about 1-2 pounds (0.5-1 kilogram) per week.
In other words, my water fasting results were more than 10 times better than what you can get on your standard, "doctor's approved" weight loss diet.
But the truth is, more than two thirds of my awesome weight loss results had nothing to do with my body fat.
So even though water fasting IS one of the fastest fat loss methods on the planet, you'll have to sacrifice a lot of your lean body mass to lose so much weight so quickly.
But this preventable and reversible loss of your lean body mass is not just a problem with water fasting. Trying to lose body fat really quickly (while holding on to as much of your lean body mass as possible) is easily the single biggest problem in the weight loss community.
Because this issue is so hard to avoid, many rapid weight lost diets trick you with a big fake drop of the number on your bathroom scale. And while you celebrate those fake weight loss results, you stay completely blind to the fact that you probably lost little or no body fat at all.
Again, this article is about water fasting, so I obviously can't go into all the details here, so let's get on with why following in my footsteps could be a terrible idea for you.
Why repeating my experiment is probably a bad idea for you
I know that the more I tell you not to repeat my experiment, the more tempted you will be to try and lose weight as quickly as I did.
So I'm not going to.
Instead, I'm going to warn you about the risks involved, and give you some tips on what you can do to minimize the damage.
So let's take a look at the two major reasons why water fasting for weight loss could be a really bad idea for you.
1. The damage water fasting can do to your body
This experiment proves water fasting can help you burn a hell of a lot of body fat really quickly. And while many people survived fasts longer than a month, some death cases have been recorded as well.
Not just anecdotes and stories, but actual medical cases. And those deaths happened in spite of those poor people having plenty of body fat reserves left.
I won't go into the details here, but you should know that those deaths are only the tip of the iceberg when it comes to the potential dangers of pure water fasting.
I'll only say it's quite overwhelming on how much of the advice I got from the fasting community turned out to be completely wrong or downright dangerous, after I finally did my own research into the actual science on water fasting.
Because of that - and if you still want to fast for rapid fat burn - I would recommend you do a muscle sparing fast instead of a pure water fast any day of the week.
Again, I won't go into the details on how muscle sparing can increase your fat burn rates without destroying your lean body mass here, so let's take a look at how water fasting can affect your mind.
2. Water fasting can mess with your head as well
Here's the worst case scenario.
If you don't know how to handle intense hunger and strong food cravings during a water fast, you will suffer at best, and fall face first into a food binge at worst.
But even if by some miracle you make it through the entire fast, all those bottled-up feelings of denial and suffering will explode in your face as soon as you allow yourself to eat again.
Before you know it, you will be standing in front of your fridge, stuffing your face with any fattening, unhealthy and junky food you can get your hands on.
You have walked right into the yoyo dieting trap, without even realizing it. And the only painfully useless consolation I can offer, is that you aren't the first.
I know this because I went through this dieting-binge-dieting cycle many more times that I'd like to admit.
Today, after more than a decade of research into human behavior around food, I am quite capable of surviving that relentless assault of hunger cravings that usually happens at the beginning of a fast.
But if you don't feel fully confident you can actually handle such severe dietary restrictions, I would again recommend you take a look at muscle sparing fasting.
On to taking a closer look at what happens to your muscles during a water fast.
In this part of the guide I'll explain everything you need to know about water fasting and muscle loss.
Here, you'll see the science on how much muscle mass you can expect to lose every day during water fasting, a ketodenic diet and a mixed diet.
(This will help you understand that the loss of muscle mass isn't just a problem with water fasting, but with standard weight loss diets as well.)
I'll also talk about what you can do to fully prevent that unnecessary loss of muscle mass.
Let's dive right in.
Muscle loss during water fasting, a mixed diet, and a ketogenic diet
I found a study that took a really close look at muscle loss during water fasting, a ketogenic diet, and a mixed diet.
Here's how the study went down:
The people on the mixed diet and on the mixed diets both ate 800 calories a day.
And of course, the people doing a water fast, ate 0 calories a day.
Here are the results of the study:
|Weight loss||Fat loss||Muscle loss||Water loss|
|Mixed diet||277.9 g/day||166.7 g/day||9.5 g/day||101.7 g/day|
|Ketogenic diet||446.6 g/day||163.4 g/day||17.9 g/day||265.3 g/day|
|Water fasting||750.7 g/day||243.1 g/day||50.4 g/day||457.2 g/day|
On the surface, this table tells you that you'll lose muscle mass 5 times faster during a water fast than on some standard, 800-calorie weight loss diet (50 grams a day versus 10 grams a day).
But there's a catch.
The speed of muscle loss isn't the only thing that matters
While it's true that water fasting will destroy a lot of your muscle mass per day, you also have to consider how quickly your total weight (or better yet, your body fat) will be coming off.
So let's say you wanted to lose 20 kilograms (44 pounds) of total weight (this is how most people set their weight loss goals anyway).
Here's how long that would take on a water fast, a mixed diet, and a ketogenic diet:
|Days||Fat loss||Muscle loss||Water loss|
|Mixed diet||72 days||12.0 kg||0.7 kg||7.3 kg|
|Ketogenic diet||45 days||7.3 kg||0.8 kg||11.9 kg|
|Water fasting||27 days||6.5 kg||1.3 kg||12.2 kg|
As you can see from the second table, you won't actually lose 5 times as much muscle mass on a water fast as on some standard diet.
(In fact, you won't even lose twice as much muscle mass.)
Because, even though you'll be losing a lot more muscle per day on a water fast, you'll also reach your final weight loss goal almost 3 times faster.
And that's exactly why you'll lose a lot less muscle mass in total.
But let's take an even closer look at the loss of muscle mass during a water fast.
A daily breakdown of muscle loss during a 21-day water fast
The table above, the one that says you'll be losing about 50 grams of muscle mass per day, may fool you into thinking that you'll be losing 50 grams of muscle every single day.
Here's what one study on muscle loss during water fasting found out:
So the truth is, you'll be losing a lot more muscle mass in the early days of your fast than in the later stages of your fast.
This happens because of the so-called protein-sparing effect, but sadly, that doesn't kick in until quite late in the fast.
And now for easily the most important question when it comes to losing muscle during a water fast:
How to prevent muscle loss during water fasting
First of all, there's no way to do a 100% "pure" water fast without losing muscle.
But if you're willing to eat (or drink down) a tiny amount of protein during your water fast, then it's actually possible to completely prevent nay loss of muscle during fasting.
How can you do it?
According to research, all you need is around 0.6 grams of protein per pound (or 1.3 grams of protein per kilogram) of your "ideal body weight".
If you're willing to eat that small amount of protein (or even drink them down in a form of protein isolate), you can fully prevent any loss your muscle mass WITHOUT slowing down fat loss.
Technically, this can no longer be called water fasting, but muscle sparing fasting (you can find more details on muscle sparing fasting here).
Time to tackle the mysterious subject of water fasting ketosis.
In this part of the guide, you will learn everything you need to know about water fasting ketosis.
I'll explain how water fasting can help you reach your absolute highest possible fat burn rates, which is easily the single biggest benefit of ketosis.
You'll also see the science on how long it actually takes before you can enter ketosis during a water fast. You'll also learn about one of the most dangerous problems of water fasting ketosis.
I'll also tell you why it is a very good idea to avoid one of the most common mistakes people make once they already reach ketosis during a water fast.
Now that you know what you're getting yourself into, here's a quick overview of everything that's covered in this guide:
The single biggest benefit of water fasting ketosis
Simply put, ketosis is a state where you get to enjoy your absolutely highest possible fat burn rates.
If you're on your regular diet, your body can draw energy from a couple of different sources (so not just from your body fat reserves). Those other, non-fat energy sources are the main reason why your fat burn rates stay on the low end, even if you start eating less food.
But during a water fast, because you're eating no food at all, those other energy sources in your body will be completely wiped out after a while. Once that happens, your body will enter full ketosis, and in that state of full ketosis, your body will have no choice but to rely almost exclusively on your body fat reserves.
With no other energy sources available, ketosis will trigger some pretty amazing fat burn rates in your body.
Water fasting is one of the fastest ways to reach that state of super high fat burn. And a lot of people do a water fast just for this reason.
There's only one problem with reaching ketosis through water fasting.
How long does it take to enter ketosis on a water fast?
According to one water fasting study, it can take up to 3 days before your body can reach full ketosis during a water fast.
Because, even if you stop eating food completely, your body will still have to burn away your non-fat energy reserves first. As long as any of those are around, you won't be able to reach full ketosis.
I call these non-fat energy reserves "fat burn blockers", because as long as there's even a trace of them left, your body will never be able to fully focus on burning away just that stored body fat.
In other words, if you do a water fast and decide not to do anything to speed things along, you probably won't get to reach your highest possible fat burn rates in full ketosis before day 4.
How many extra calories will you burn in water fasting ketosis?
Most people, including the so called experts, will tell you that weight loss comes down to calories eaten versus calories burned.
But water fasting ketosis can offer one huge advantage when it comes to melting away that stubborn body fat.
Because, according to modern science, water fasting ketosis can help you burn an extra 325 calories per day!
So that's on top of everything you'll burn because you're not eating food.
Why does this happen?
Well, your body will have to work much harder to extract the needed energy from your own body fat reserves, than it would have to if you actually ate food.
So all that extra work your body will need to do to extract, convert, and burn off the calories stored in your own body fat reserves, keeps delivering a major fat burn boost for as long as you stay in water fasting ketosis.
The #1 problem with water fasting and ketosis
Even with all the fat burn blockers gone, your body still won't be able to extract enough energy from your body fat reserves alone.
It won't matter that you already reached your highest possible fat burn rates, your body will still need to extract some energy from your vital body mass too.
Yes, even after reaching full ketosis, your body will still be forced to burn away some of your muscle mass and vital organ tissue for energy. Just so you can survive the water fast.
One study has proven it's possible to destroy as much as 13 pounds (5.9 kilograms) of your vital body mass during a 21-day water fast.
That destruction of your vital body mass is the price you will have to pay to hold on to those high fat burn rates in water fasting ketosis.
A common mistake people make in water fasting ketosis
One of the biggest mistakes I've seen people make is try to stay as active as possible during ketosis. Some people even force themselves to exercise, no matter how tired they feel after reaching ketosis during a water fast.
And the sad part is, I have yet to meet anyone in the water fasting community (even among the "professional" fasters), who understands just how big of a problem this can be.
In one study, people exercised at a pretty normal pace after they already reached full ketosis.
And the crazy thing that happened was that they destroyed over 100 grams of their lean body mass per EVERY SINGLE HOUR of exercise.
So not only will you lose some of your lean body mass (that's even if you stay completely inactive during a water fast), but you WILL destroy a lot more of it, if you force yourself to exercise once in ketosis.
So yes, you might burn off a few extra grams of body fat if you stay active during a water fast. But this extra fat loss will come at a very high price of the damage you'll cause to your lean body mass.
(Your lean body mass not only includes your muscle, but your vital organs as well - like your heart, for example.)
This is why you need to drink a lot of water while in ketosis
One last thing about the importance of drinking enough water for as long as you stay in ketosis.
(That's on top of the fact that it's a very good idea to keep your body properly hydrated at all times for health reasons.)
Drinking enough water keeps your metabolism revved up.
More precisely, without enough fluids, the calorie burning process in your body called "thermogenesis", will slow down.
You can learn more about the calorie burning process of thermogenesis (and many different ways of boosting it) here.
All in all, there really isn't all that much you need to know about how to do a water fast.
With just one major rule (drinking enough water throughout your fast) and a few small water fasting tips (not standing up too quickly) to follow, water fasting is one of the simplest "diets" on the planet.
But just because water fasting is simple, that doesn't mean it's easy.
But with the scientifically proven fact that you hunger can literally disappear, water fasting has one major thing going for it (that most other diets and cleanses don't).
Also, water fasting can destroy about 5 times as much muscle mass per day, than your standard, 800 calories a day, mixed diet.
But the muscle loss during a water fast isn't as critical, because you'll also reach your weight loss as much as 3 times faster than on a standard diet (meaning you won't lose nearly as much muscle mass in total).
But no matter how you spin it, the loss of muscle mass is pretty much inevitable during water fasting (that's IF you insist on doing a pure water fast).
But if you can eat (or drink down) 0.6 grams of protein per pound (or 1.3 grams of protein per kilogram) of your "ideal body weight", you can fully reverse the loss of muscle mass.
(And you get to do it without slowing down those sky-high fat burn rates water fasting CAN deliver.)
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