Water Fast Results & Pictures: 3, 5, 7, 10, 14 Day Before & After

Let’s get straight to it. I recently did a 14 day water fast, which I decided to document very thoroughly, why you’ll be able to see the weight loss before and after photos for day 3, 5, 7, 10 & 14.

14 day water fast before and after weight loss results pictures

Here are the results jumping straight from the time I started to the time I ended – intrigued? I documented everything in great detail

My experience, journaled

Being someone who frequently fasts, I don’t really get some of the side effects that most people do when starting out (which is great) – trust me, I did have the symptoms when I initially started out. It means that if you’re starting out, you’re probably bound to definitely feel sluggish, hungry & cold and perhaps experience other symptoms as well, as your body isn’t fat adapted (fasting may be easier for you if you’re used to a keto diet).

According to Healthline, it takes 4 to 12 months on a keto diet to become fat adapted, however if you’re fasting, it will happen a lot quicker as you’re not triggering any insulin response. Basically your body isn’t used to using fat for fuel instead of the usual glycogen, and converting over to that fuel source when you’ve been consuming an excess amount of carbs your entire life, will take time.

On a different note, becoming fat adapted has definitely lead me to having fewer hunger cravings. I used to crave sugar like it was a class A substance, which it honestly should be classified as, if you ask me, which I fortunately don’t anymore.

Also, scroll down further if you want to see some of the results pictures from various times throughout the fast. I didn’t notoriously take photos quite as notoriously as I would have wanted, but did still manage on several occasions. This is not to be confused with people that do a 3, 5, 10 or 30 day egg fast – in this time, I only consumed coffee, water, electrolytes and one sparkling water on occasion.

Day 0 (24 Hour)

This was basically when I started my fast. My dinner was at 8pm that night, and I decided to embark on what would be my longest fast so far, and probably ever to be honest. I will likely do an extended one every single year, as well as some shorter ones sprinkled out throughout the year but I don’t believe there are many additional benefits going beyond 15 or so days. Anecdotally, I have heard people say they really start experiencing changes on day 10, which was why my initial goal was to do 14, which is why I put on enough weight to be able to sustain it for so long. I’ve also found it vastly easier to start a fast after eating dinner, rather than eating breakfast in the morning and then fasting, at which point I will surely experience hunger later on. Either way, I started out at 187.4 lbs at 8pm, with lots of food, water and carbs in my system.

Day 1

Honestly I breezed through it. Having gone through this as many times as I have, I didn’t feel any of the symptoms I felt when I just started out. However, when I just started fasting, day 1 felt like D-Day and I was probably ready to rip someone’s head off had they cut in line. Yup, I was majorly irritable the first time. This time, nothing. Besides that, during my first fast, I sat underneath 2 blankets with a sweater and pants on in 72 degrees and was freezing like crazy. This time around, I didn’t experience any of that and was wearing my usual shorts outside in 45-50 degree weather. By 8pm, my weight was down to 182.2. Yes, apparently I had dropped more than 5 pounds in a mixture of fat, water and food weight. Pretty crazy to think about.

Day 2 (48 Hour)

Day 2 was easy this time around. I cannot complain at all and I didn’t really feel any negative side effects. During earlier fasts, this has really been when a lot of the negative side effects have started subsiding. It was really the time where I started noticing major improvements in my mental clarity, which is one of the most fascinating things you’ll experience if you try it out yourself. While you may still be thinking about food (a lot), I do find my mind to be working at 130% when I am not eating food for extended periods of time. At 8pm my weight was down to 179.6, and given that that is nearly a 3 lbs drop from 24 hours earlier, my body was obviously still shedding a lot of water and carb weight, as I don’t have a 10k calorie metabolism per day. That’s for sure.

Also, this was the day when I really started getting bad breath from fasting, which is a common occurrence, and supposedly even possible doing intermittent fasting or following a keto diet can give you bad breath because you increase the ketone production which is a gaseous bodily compound helping you burn fat. Yes, it’s nasty and you’ll get a white coating on your tongue. If you have any self-respect, you’ll buy a tongue scraper from and use it as if your life depended on it. It will do wonders, girlfriend-confirmed. I personally got this one and it has made me feel like a respectable human being again, not walking around with a breath that could kill an elephant, and for $10, it’s worth it – get the hint?

3 (72 Hours) Day Water Fast Weight Loss Results (before & after pictures included)

I am an avid consumer of coffee, and black coffee, or caffeine pills, is still something I do throughout the fast. However, probably the same way that you might experience a considerably lower tolerance for alcohol if you haven’t had any for a long time, you probably have an elevated sensitivity to coffee when you’re not eating. Say that the food is absorbing some of the effects, or whatever you may think is going on, my tolerance was definitely affected. I do know that I get jitters when I drink too much coffee but usually it won’t be too bad when I am actually eating. On day 3 – oh boy did I have too much coffee. It was really bad and has definitely taught me a lesson. It was up to a point where I really struggled focusing and that amount of coffee shall surely not be repeated during a fast, and I didn’t even think it was a whole bunch more than I would usually drink. At 8pm, weight was down to 177.6 lbs, meaning the result of my 3 day water fast was a weight loss of almost 10 pounds.

While the rate of weight loss was surely slowing down, it was still too high to believe that it was only fat being lost. I was surprised I’d managed to lose 10 pounds in 3 days, although a lot of it would be coming back if I was to start eating. Still, crazy.

3 day 72 hour water fast before and after weight loss results
It was clearly cold on the third day, or I simply had significantly puffier nipples on the photo on the left. The first picture was taken after I had dinner, so I obviously lost both the food that was in my stomach as well as a good bunch of water weight. However, it is quite noticeable that there’s a lot of weight that’s starting to come off. These before and after result photos clearly show the weight loss power of not consuming any calories for a period of 72 hours.

Day 4

Day 4 was weird, at least considering that I have fasted on a bunch of occasions before, but however probably not unexpected. Up until this point, I had not consumed any electrolytes. I half wanted to see how long I could go before starting to feel bad from probably a lack of electrolytes and day 4 was definitely the time. I felt really quite nauseous and attributed it to a lack of electrolytes. Is that surely why I felt like that? Who knows, however I didn’t intend on breaking my fast this early knowing that I had put on a significant amount of weight to do this project, and I had previously breezed through this time during different fasts. However, I did consume electrolytes. I have a supplement that I take which just ensures that I get the right proportions and what not, and it makes life easier. The nausea did somewhat go away over time, although it never really disappeared. 8pm came around and my weight was 175.5 lbs. Still dropping those pounds!

Day 5 (before & after pictures as well)

Day 5 came around and brought with it a lot less nausea than the previous day, although there was still a little bit. I doubled my electrolyte intake, although there was sporadic nausea. 8pm and and the weight was 174.7 lbs. My weight loss rate was definitely dropping and nearing a state where it was more or less just fat being burned. Assuming a pound of fat equals 3,500 calories, a .8 pound weight loss would be the equivalent of 2800 calories being lost. Probably not far from my metabolic rate.

5 day water fast before and after weight loss results


Day 6

Day 6 came around and there was no nausea left at all. However, later on I managed to get a significant amount of pain in my ear. I have a feeling like I hit it or something less than intelligent and went to bed that night sleeping horribly because of the pain. Because of my Viking descent, I did not take any pain killers. At 8pm the scale was reporting me weighing in at 172.6 lbs. Back on track to losing more weight than my metabolism would allow. I’m not quite sure I had the electrolytes I should have had. Day 6 marked the time I had managed to lose 15 pounds (with a rounding error). It was one where I felt rather cold, especially hands and feet.

Day 7 (with before & after results pictures)

The good news about day 7 was that a lot of the pain in my ear had gone away and I wasn’t feeling nearly as cold anymore either. The less than great news was that I definitely did not drink enough water. I didn’t feel bad, I just didn’t feel great. Still, having easily gotten through this time on a previous fast, I didn’t see it as a major sign of concern.

The crazy thing was that my weight came in at 167 lbs. Yes, I had officially lost 20 pounds in a week. Crazy. Not going to lie, the result kind of freaked me out and I made sure to increase both my water intake as well as my electrolyte intake as well. For all those people out there, it shows that you can lose a lot more than both 5 and 10 pounds in a week, and that you don’t need 2 weeks or a month to achieve those results if you really set your mind to it, and that the whole idea of losing 2 pounds a week is really conservative if you go for a more significant measure like water fasting.

7 day water fast before and after weight loss results


Day 8

Day 8 was massively different from the night before. I woke up feeling like the king of the universe. It was really, really great. Mental clarity and all that other good stuff. Nothing bad to say about that day. The pain in my ear was gone as well which was another great thing and I made sure to get enough water and electrolytes as well. 8pm came around and my weight was 168.6 lbs. I wasn’t really demotivated by the fact that the scale had gone the other way as I hadn’t felt entirely great the day prior and it was probably a mixture of dehydration and a deficiency of electrolytes. For as long as my mood was great and I was feeling great, I was more than happy with that number. Day 8 of my previous fast was when I started feeling a little bit too iffy, and day 9 of my previous fast was when I decided to call it quits given how I was feeling, despite having aimed for 10. Oh well, while I didn’t reach my goal that time around it did set me up with the knowledge necessary to do this longer, successful project.

Day 9

I woke up feeling great. The pain in the ear was completely gone, which I really didn’t mind. Day 9 definitely showed that I had managed to previously keep up with my water intake, which was great, as the 8pm weigh was substantially lower than the day before, coming in at 166 lbs. Back to drinking more water. Admittedly, hands and feet were pretty cold. I did keep up my electrolyte intake and felt great from the moment I woke up to the moment I went to bed. It also marked an important milestone as it was now officially the longest fast I had ever done.

Exciting. Now wandering off into new pastures. I definitely still felt great, although I decided to increase my electrolyte and water intake once again.

Day 10 (with before and after pictures)

I woke up feeling alright, not great, but I could quickly see when I was doing my workout that I was losing steam at a rapid pace. I guess that is what happens when you don’t eat for 10 days. My strength wasn’t impressive, however, it’s cool to see that I can now do significantly more pullups than I could do when I started because of my lighter frame. Apparently lightening the load more than 20 pounds make pullups easier. Who would have figured.

At 8pm the scale showed 164.5 pounds. While there are reports of people out there managing to lose 20 pounds in 3 weeks, reality is that you can do it in a lot less time. In my case, my results were that I managed to achieve a weight loss of 22 pounds during my first 10 days of the water fast, without having any significant negative experiences. Despite there being hiccups, I would never describe my experience as being miserable, even if there are other that claim that. I also never experienced any form of euphoria throughout, although I do think my mood was elevated for most of the time.

It was great to see that it’s actually not impossible to lose 20 pounds in 10 days, although a lot of the weight lost would probably come back as I started eating again. If it had been purely fat, 20 pounds would equal 70,000 calories lost or a daily caloric deficit of 7,000 calories. Probably not too realistic.

10 day water fast before and after weight loss results

Day 11

Woke up a bit dehydrated, the mood was good. I got a pretty good workout in but nothing that would break any world records. I was still happy with where I was at anyway. I felt nice and warm, both hands and feet and when 8pm came around, the scale showed 166 pounds, which clearly showed I was pretty dehydrated the night before. No wonder I was feeling a little bit off.

Despite really having felt like quitting the night before, I woke up in the morning with rejuvenated energy towards the project and continued without any trouble.

Day 12

Woke up with a morning weight of 163 pounds, however was back up to 164.5 by 8pm. I did feel a little bit more lightheaded, but besides that I felt great. Both my hands and feet were still warm. It seemed pretty clear that my weight was getting to a point where the weight loss was rapidly declining, most likely because I had lost any and all excess water and carb weight – was I turning into a superhuman yet?

Day 13

There was a little bit of a headache in the morning and some clear dehydration but both of those went away when I got some water in my system. By the time I stepped on the scale in the morning, it was saying 163.4, so I was probably mainly dehydrated the night before. I got a phenomenal workout in and felt great throughout, honestly barely any lightheadedness. At this point I think I could go for another 7-8 days and potentially make it 21, which was really what I was my stretch goal, however, sudden changes to my social schedule meant I chose to break my fast on day 14.

During previous experiences of not eating for extended periods of time, I’ve started feeling a bit iffy a day or so prior to the goal I had set for the duration of my fast. My 10 day fast, I started feeling iffy on day 8 and especially 9, why I previously chose to break it then. I never really managed to get to that point this time, perhaps because I mainly had a stretch goal and never got close to it. It was probably more psychological than anything, or an electrolyte deficiency. Who knows.

How to break your 14 day fast – and how I did it

I hadn’t planned to break it and start eating again, but life called for me to do so anyway. While the general recommendation is to break such a long one with bone broth and other small meals and gradually increase your food intake, being the general savage I am and having a serious passion for pizza, that has always been my go-to food.

Has my stomach previously felt funny after breaking a fast, perhaps because I chose to feed it such a divine mixture of carbs and fat, perfected by the Italians? Maybe. Have I always enjoyed that first bite of pizza like I was a person finding water after being stranded in the desert for a week without it? Yes.

While I realize it may be living life on the edge, is a life living in fear really worth it? Don’t follow my example.

Overall, I was very happy with both the results, the pictures I managed to take and how I only seemed to have relatively minor struggles along the way. Although I broke the fast a couple of hours before I had officially gone 14 days, it was only a matter of a couple of hours. After consuming all the pizza any human could consume in one sitting, I was already looking forward to breakfast burritos I had planned for the following morning.

Check out these before and after pictures of my 14 day water fast.

14 day water fast before and after weight loss results pictures

Day 21

While no longer on a fast, I just wanted to show how my weight rebounded after starting to eat again. I can report that 7 days after ending my fast, my weight was now up a significant amount, although still means I managed to lose more than 10 pounds in 20 days.

Trust me, even if I might not have felt hungry throughout, it doesn’t mean that I wasn’t thinking about food. I figured out how to make bone broth as well as how to make hummus on this fast, and while I did manage a trip to the grocery store, I do think it was such a trip that previously triggered me to end a previous fast. If you’re fasting, and especially if you’re new to it, you will still want to stay away from other people eating and grocery stores as much as possible.


While I may not have done a 28, 30 or 40 day water fast, I am very happy with both the results, the mental clarity and everything else I experienced. I stopped when I felt it was time to stop and never felt I was putting my body in a state that wasn’t safe. I could, however, preferably have gone without the crazy amounts of coffee I had on day 4 which was rather uncomfortable. Way more uncomfortable than any food cravings I’ve ever had. It definitely showed that it is really quite possible to lose a lot of weight in a week, 2 weeks, in 30 days, a month or even 3 months whether your goal is to lose 50 pounds or some other number. I had previously tracked my weight on my longest previous one so as to somewhat be able to know how much weight I wanted to be at before I started to be sure I could do a 14 day fast without adverse consequences, why I knew that I was probably needing to have 30 pounds that I would be willing to lose, and able to before starting. If I remember correctly, I started feeling bad around a body weight of 157 lbs previously, so that was basically my bench mark – 157 plus 30 pounds to lose. While I was considering having 40 pounds that I would be ready to lose, I also knew that I probably didn’t want to go much further than a 14 day fast, and as the most dramatic results in the mirror come towards the lower parts of your weight (especially that stubborn back fat, which is where I carry most of my fat), and I knew what weight I wanted to end up at, I thought 30 was a good number. While I did go to the gym and did heavy lifting throughout, it’s important to note that I didn’t do any cardio sessions to burn additional calories, why I consider this weight loss more or less without exercise, showing just the results that can be achieved if you set your mind to it.

Also, most of the experiences I have read online will say you reach a stage where your body starts giving some clear indications that you need to break your fast, however, I do associate most of my inconsistencies of not getting enough electrolytes as I definitely saw positive improvements the days following me feeling questionable when I increased electrolytes.

On the topic asked by many of what happens if you don’t eat for 2 day, 3 days or even a week, well, at least now you have a fairly detailed report of my experience.

By now, I have realized that this post has turned into a lengthy one, however, I do have images that are more specific to how my face transformed throughout this project, as well as a picture of a potential double chin (admittedly that wasn’t really where my main concern was, storing most of my fat on my lower back). If at all you are interested in trying out an extended fast yourself, I suggest you read this article I wrote on the topic.

Now on to some of the technical parts of the topic, as well as the scientific things your body goes through, and what you need to be aware of. Yes, it’s going to be a long read. I’ve done my absolute best to back everything up with scientific studies and references, so as to squander any myths that water fasting (assuming done correctly, and you don’t have a specific reason not to do it) can be done safely, with major benefits.

What is water fasting?

Simply put, water fasting is a type wherein you will only consume water, bringing your calorie intake to zero. Other people mistake water fasting with broth and juice detox, both of which still entails consuming calories because broth and juice contain calories or sugars. True water fast does not involve consuming any calories.

Does it work?

Like you, I’ve had my own few shares of doubts about fasting, even more so water only. I’ve always wondered if not consuming any calories would be beneficial to our bodies, and whether it would really work. So, like any sensible being, I did my research, read blogs about various experiences on different types, and consulted my doctor about the subject first before trying it out.

It has been around for centuries, practiced by humans since pre-history, and this fact should tell you that it does work. A lot of research has been centered on how it works and what its benefits are. It is practiced by a lot of people for other means besides achieving a caloric deficit to lose weight, such as:

  • preparation for medical procedures;
  • detox or toxin cleanse and body regeneration;
  • religious and spiritual practices; and
  • therapeutic intervention to combat or lower risk of diseases.

In my case, I did it to shed off fat and lower my overall weight safely and effectively, alongside reaping the numerous health benefits that it offers.

Still not convinced? Then let me give you a quick list of success and experience stories that inspired me to try it for myself:

  • In this blog post, the author did a 10-day water fast, which resulted in the following:
    • improved digestion
    • lowered blood pressure
    • effective detoxing
    • loss of 15 pounds of body weight

Upon experiencing these health benefits, the author then made a commitment to repeat the success once to twice every year.

  • These testimonials of patients from a clinic in Hawaii discuss not only the health benefits of water fasting, but also its spiritual and mental benefits. Here are some snippets of these wonderful success stories:
    • Spiritual & Mental – Sarita did a 21-day fast, split in equal parts of 7 days doing green juice, water fasting and juice only, respectively. She felt transformed after her meditation, had a better relationship with food, and felt a deeper sense of gratitude for the things she has afterwards.
    • Health – Ari did a 10-day fast to get back in the normal weight range, treat her chronic back pain, and get her energy back up. Afterwards, she lost 10 pounds (and kept her weight off), got rid of both back pain and body odor, improved her vision, and felt more energized compared to before.

Wanting to lose weight?

To burn fat deposits, you need to achieve a caloric deficit either by reducing your calorie intake or upping your energy expenditure—between these two, the former is a more efficient way to achieve a caloric deficit.

Stored fat is the body’s Plan B for energy resource, not its Plan A. Your body will use up external sources of glucose first, such as the calories from the food that you eat. The only time our body burns fat is when there is no glucose left to be used, which is why you need to have a caloric deficit. If there are calories readily available for your body to use, fat loss won’t happen.

So, how does it help?

When you don’t eat, you’re limiting your body’s calorie intake. There are numerous types based on meal schedule—short-term, intermittent fasting (IF), alternate day (ADF), and prolonged —and based on the type of food or fluids that you consume—broth, juice, etc. Depending on what type you’re doing, the number of calories you consume will differ.

For water fasting, you won’t be consuming any calories at all. And by doing so, your body will go into ketosis right away, wherein your body burns fat reserves as a source of energy. This is a guaranteed way to efficiently burn fat to lose weight!

Like I’ve mentioned, losing weight is just one of the many benefits. Let me give you various research that have shown the benefits throughout the years:

What happens when you don’t eat for a day, 2, 3, 5 days, or even a week?

The short answer is that when you don’ eat for 1, 2, 3 days, or even a week is that your body starts producing ketones, making it better able to use fat for fuel instead of the usual glycogen, which means you will be burning fat at a more rapid pace than you otherwise would be. Not eating for an extended period of time is by far the easiest and quickest way to lose a significant amount of body fat as well. We’ll go through some of the more intricate details of a prolonged fast under the extended benefits section.

Benefits of a water fast

Autophagy | Stem Cell Regeneration | Prolong Lifespan

This study shows that in order to reap the full benefits of a water fast, you have to do it for 48 hours or more (see the section on the different stages to know why). The clinical trial shows that a 72 hours of no calories is beneficial for the human body and may even prolong lifespan. In cancer patients, it protected them from toxicity from chemotherapy.

Basically, it was found out that ones that lasts for 3 days or longer can “reset” some of our bodily functions and components, specifically in our immune system. Our bodies undergo autophagy and stem cell regeneration, recycling old, damaged proteins, microbes, and cell organelles to build new tissues and cells. This leads to stronger immunity and protection against cell degeneration. Other people call this as “self-cleaning.” and it is generally believed that the body’s self-cleaning process, autophagy, really starts kicking in majorly around day 3-5 of not eating, although the scientific study of autophagy is still in its infancy.

For further reading, you can check this article by Suzanne Wu from University of Southern California, which delved deeper into the topic and included interviews with the researchers.

Lowers Blood Sugar & Pressure | Reduces Risk for Cancer and Diseases

Widely known by people interested in the topic, Dr. Jason Fung (who wrote two of my favorite books on fasting, diabetes, and obesity: “Obesity Code” and “The Diabetes Code”) proved that it can reverse type 2 diabetes and cure prediabetic symptoms. People were able to lower their blood glucose level, blood pressure, and weight. Here are some success stories that may inspire you!

Fasting is a ketogenic process, and as your fats are burned, ketones are produced. In this study, evidences have shown that the production of ketones can selectively starve tumor and cancer cells. Since you won’t be supplying your body any calories/glucose, cancer and tumor cells, which are glucose-dependent, will starve and die. On the other hand, normal cells can use ketones for energy!

Reduces Hunger | Easier Weight Loss & Appetite Control

In this study, both obese and normal-weight young adults did a 12-84 hour fast, and after 3 days, there was a significant lowering of their ghrelin (hunger hormone) levels, thereby controlling their appetite. They eat less and feel full easier afterwards, which is important for easier weight loss and avoiding weight regain! Their experiences are very much in line with what I experienced myself.

The experiences also turned off certain food cravings, especially in women, which will make it easier for you to have a healthier relationship with food.

Improved Metabolism & Muscle Strength

An increase in human growth hormone (HGH) levels happens during prolonged fasting. HGH promotes growth and muscle strength, and also improves weight loss and metabolism.

This study involved nine men who went on a 48-hour fast and this resulted to a five-fold increase in HGH production rate. In this study, ten women did 4 days and it resulted in an increase in their growth hormone, while their ghrelin (hunger hormone) levels decreased!

Improved Eating Habits

Prolonged fasting can curb unhealthy eating habits and can offer emotional and psychological benefits. It forces you to find other ways to deal with emotional or stress-eating, unlike in IF or ketogenic dieting where people can still turn to stress-eating ketogenic foods.

If you manage to stick until the end of it, you’ll see that your eating habits will improve, just like how this success story reported a better relationship with food after not eating for an extended period of time.


Our bodies may respond differently to fasting simply because we have different current health conditions, lifestyles, and genes. However, when we fast, our bodies follow a certain metabolic pattern. For you to easily understand what happens to your body as you’re going through it, let me briefly discuss the stages, based on a 5-day fast.

Stage 1: DAY 1 (0-3 hours)

At this stage, your body is still operating as usual: the food you ate is being broken down into glucose, which then goes into cells with the help of insulin to be used up for energy. Excess glucose is stored away for later use as glycogen and fat reserves.

This process of growth, wherein our body uses up available nutrients/glucose for energy and muscle growth is an anabolic process.

You will likely feel hungry on the first day of your fast as you’re not used to going extended periods of time without food and because you haven’t gotten your ghrelin levels under control yet.

Stage 2: DAY 1 (12, 14, 16, 18, 20 & 24 Hour Fast)

This is where catabolic reactions occur. The breakdown of stored nutrients happens, but your body taps into stored glycogen first and breaks it down into glucose. Your body will continue to break down glycogen until it reaches the normal blood glucose level of around 70-120 mg/dl.

However, since you’re not consuming anything to replenish your glycogen reserves, your body will deplete all the available glycogen reserves. At this stage, you’ll feel hunger due to fluctuations in your ghrelin (hunger hormone) and leptin (satiety hormone) levels. Your body recognizes that you’re not eating, so it will try to get you to eat! However, you must endure this since it will pass as you get further in.

By the end of the day, your body will switch to another pathway of energy production. Whether you’re fasting for 12, 14, 16, 18, 20 or 24 hours, it is a good practice that will let your body enter some reasonable level of ketosis, at which point fat loss becomes a lot easier. As these intervals are also considered intermittent fasting, it’s not wonder why people are using it to successfully lose weight as well.

This may also be the stage where you start noticing changes to your breath, unfortunately not for the better. If you want to, you can get a tongue scraper which can make a significant difference. I have personally used one, and the girlfriend is a big fan of it!

A very common variant of a 16 hour fast is called 16/8. You have an 8 hour eating window. Another popular option is to do an 18 hour fast with a 6 hour eating window, called the 18/6, both are considered IF. By hour 18, you’ll be generating significant levels of ketones, but the longer you refrain from eating, the more significant your weight loss will also be. There are also 20 hour variations, however, it’s really up to you to figure out how long you wish to go, especially as you’re just getting started.

For people doing a 24 hours, this is commonly referred to as OMAD (One Meal A Day). 12 or 14 hour of consuming no calories is still a great accomplishment if you have previously been used to eating, and you’ll quickly find yourself becoming less and less hungry as your stomach and body adapts! This is considered time restricted eating.

Stage 3: DAYS 1-3 (36, 48, 60 & 72 Hours)

Within 24-72 hours, your body will switch to burning fats because all your glycogen reserves are depleted, and this is what we want to happen. For these semi-long ones, the most common variations are either 36, 48, 60 or 72 hours, which will start yielding very significant weight loss. Some people may even do a 48 hour fast twice a week, which will very rapidly help with your insulin resistance as well. I personally like 72 hour fasts because they yield a significant amount of autophagy and weight loss, while still allowing you to do them during the week without having to plan around the weekend.

During stage 3, your body breaks down fat (lipolysis) to release free fatty acids, which are used to activate the metabolic pathway called ketogenesis. Through this pathway, ketones are released, and these become your body’s energy source!

Your body also burns more fat through gluconeogenesis, producing glucose for your brain. (No need to worry about these sugars being stored! Your brain uses it all up!)

At this stage, your ghrelin levels will decline! Studies show that during the 3rd day, the total ghrelin secretion of the body is even lower than 24 to 48 hours in! No more hunger pangs! When I originally started, and when I did a longer fast (more than ADF), it was really on this time that I started feeling great which is very consistent with what other people have experienced as well.

Stage 4: 72-120 hours

At this stage, your glucose and insulin levels are low due to lack of food intake, and your ghrelin levels also stay low. This is where your body is undergoing constant ketosis/ketogenesis, breaking down fats and producing ketones for energy.

This is also where your body produces growth hormones and promotes autophagy and stem cell regeneration! So, all in all, you’re breaking down fats, losing weight, controlling your appetite, lowering your blood sugar levels, and producing more beneficial hormones and cells! I have always breezed through day 4 of a fast whenever I have done one.

When doing a 36, I have always found it the easiest to start it at night. If you eat around 6pm, you go 24 hours without food, and then you can eat again at 6am. For some reason, I have always had a strong preference for starting 7in the evening, but I also do not tend to wake up hungry.

What happens when you’re doing it?

The same stages I’ve described above would happen. But what does it feel like? Will there be dizziness and intense hunger pangs? Or will you be feeling just like usual?

Expect the following when you don’t eat for 3 days:

  • Day 1: If you aren’t used to fasting, you will definitely feel both hungry, irritated and cold. There are many reports of people feeling nauseous as well at this point, some with vomiting occurring. I suspect that has more to do with keto flu and the body adapting to using fat instead of glycogen. I had previously done quite a bit of keto eating so I suspect that’s why I didn’t experience any of this.
  • 24-48 hours: I experienced some of the same symptoms as on day 1, however, I did feel a lot better on the second day than I did on the first.
  • 48-72 hours: Honestly, by the time I got to 48 hours, I was really feeling good. Improved mood, no feeling of hunger. I was still feeling rather cold, though. Especially hands and feet.
  • Afterwards: If you have been stepping on the scale throughout this experience, you will see that you probably lost more than 3 lbs, and that largely has to do with the water loss you experienced. As you reintroduce food, especially carbs and sodium that trap water, you’ll regain the water weight, although you will likely have experienced a nice 2-3 lbs fat loss as well over the course of this period of time – yes, that will happen!

How to do it properly


Consult with your doctor

First and foremost, you have to ensure that your body doesn’t have any underlying issues that can interfere with fasting. If you’re in any of the criteria below, you should discuss with your doctor whether it is safe for you to start.

  • People with severe diabetes and other chronic diseases may not benefit from it due to administration of insulin shots and other medications, which require regular food consumption.
  • Pregnant or breastfeeding women need a well-balanced meal to support the growth of the baby and lactation.
  • The elderly usually have various medications that requires them to eat regularly, and have underlying diseases that can make fasting life-threatening for them.
  • Young children and teens need a high intake of nutrients to support their growth spurt and help their bodies adapt to puberty changes.
  • People who have prior or existing eating disorder should steer away from fasting. This practice may morph into a form of abuse or punishment for them.

Determine your current total body fat percentage

Get your mind and body ready

(Before: eat less amount and focus on eating healthy food. As you’ll be going into deep ketosis, it’d be a good idea to start out with a ketogenic lifestyle before as it’s a milder version of what your body is about to experience.)


Avoid going to places that you know will tempt you

Hydrate and replenish yourself with essential electrolytes.

Make sure to stay busy. You will soon experience just how much time you’re usually spending on eating and preparing food.

Can you drink water?

Fasting only entails limiting your calorie intake, not hydration. So, yes, you can (must!) drink water.

Bear in mind that staying properly hydrated is very important. Our bodies still need to run on essential nutrients to properly operate, and if you’re not supplying your body any waterelectrolytes, there will be complications that may even be fatal. Some people supplement with vitamins throughout.

Not drinking any water while not consuming any calories spells one thing: DANGER! If you don’t drink water, it’s technically considered a dry fast. If you look around the internet, you can see there are some scary stories of people doing this – I would never do it myself.

So, please, ward off any calories from your body but DO NOT skip drinking water! With regards to how much water to drink throughout, I usually drink enough water that I don’t feel thirsty, without going out of my way to drink more. The downside to drinking too much water is that it will dilute your electrolytes, why you will have to drink more of them. If they taste anything like mine, it’s more of a chore than anything you’d do voluntarily, however definitely drink water when you feel thirsty.

I’ve read some people usually give up nearing the end of their designated water fast because they got tired of drinking solely water for days. How do you remedy this? You can simply get unsweetened and non-caloric drinks such as electrolyte drinks, green tea, and plain black coffee. I personally do black coffee as it is not believed to break a fast, and I would be reluctant to giving up caffeine. There are also people out there that will drink lemon water as it doesn’t contain any calories, nor carbs or protein, why it won’t affect your insulin and therefore not be an issue.


Electrolytes are minerals in body fluids, which you need to balance the amount of water in your body and control your body’s pH level. When you’re low on electrolytes, you’ll start to have muscle weakness, cramps, respiratory problems, and even kidney failure. Samples of electrolytes are sodium, calcium, potassium, chloride, phosphate, and magnesium.

You usually get electrolytes from the food and fluids that you consume. During water fasting, since you can’t consume any food, you have to increase your drinking water’s electrolyte content. Although both tap water and mineral water already have electrolytes, you can also buy electrolyte-enhanced bottled waters for more electrolyte content.

And if you’re looking for some drinks with flavor, you can opt to buy some non-caloric electrolyte drinks such as Gatorade and Pedialyte.

I personally take an electrolyte supplement throughout, which you can see from my journal. It tastes gross but it has definitely made me feel a lot better on a range of occasions.

How long is it safe to do?

It will depend on how much body fat you initially have to know how long you can go fasting. The more body fat that you have, the longer you can go on. It’s very dangerous to go beyond what your body can endure! Therefore, it’s very important to consult with your doctor first and measure your body fat percentag. I have put on weight for a couple of extended fasts before just to make sure I had the necessary amount of fat to sustain it for longer periods of time.

The ideal range of body fat percentage is 10-22% for men and 20-32% for women. Higher than these body fat ranges, and you’ll risk having diabetes, heart diseases, high blood pressure, etc.

However, body fat percentage can be lowered to 10-15% for men and women athletes and up to 3-5% for men bodybuilders (8-9% for women bodybuilders). But if you go lower than this range without any medical supervision, you’ll suffer negative consequences (low energy, hormone imbalance, low fertility, headaches, heart diseases, etc., and even potentially worse results than that, too)!

Our bodies still have what we call essential fat that is critical for our bodily functions to proceed. Having too little body fat is just as bad as having too much of it—both are extremely unhealthy!

I’d also like to highlight this study with more than 1,400 participants eating 200-250 calories per day, so not quite an extended water fast, however they reported no adverse effects from this diet which almost resembled a zero-calorie diet.

Surround yourself with positive people and turn to your hobbies


How to break a 3-day water fast and what to eat after

It’s very important to reintroduce the right type and amount of food slowly into your system when breaking the fast. The refeeding phase can get tricky. And if you’re not careful, you can do more harm than good. After getting used to ketosis, suddenly getting an influx of carbohydrates will cause a flood of insulin in your body, which can cause health complications.

Basically, you must start with a small, light meal. Break it with bone broth or unsweetened/diluted fruit juices first before eating solid foods. Strictly avoid any heavy and oily food! This will upset your stomach. If you want to introduce some solids, start with soft solid foods first, such as pureed vegetables.

Increase the amount of food slowly, adding only small increments over a period of time. To avoid complications, follow this guideline.

Also, there is nothing better in the world than having a cheat meal afterwards. When you’ve made sure that your stomach is back to normal, and indulging in some of the things you were thinking about while you weren’t eating – it’s truly great! And trust me, you will definitely be thinking about food throughout your experience.

How much weight will I lose?

Apparently, one pound equates to 3,500 calories. In general, our bodies need roughly 2,000-3,000 calories per day. So, if you limit your calorie intake to 0 in the span of 72 hours, you can lose up to around 2-3 pounds reduce your calorie intake by 1,000, you’ll lose two pounds in a week without counting the energy expenditure. Taking into account the fats that you’ll burn due to movement and basal metabolism, you can lose around 5-10 pounds in just 3 days!

If you notice your weight coming back up afterwards despite adhering to a proper diet, don’t be too alarmed. This might just be water weight; our bodies retain more water especially if you’ve been consuming sodium and carbs once again. (Remember that time your face became bloated after eating instant ramen? Yup! That’s water retention, pal!)

In my experience, I lost roughly 10 pounds after my 3-day water fast. This is obviously a huge achievement and would otherwise take significant effort if you go by a more traditional calories in, calories out approach.. Although around 7 pounds of this might be contributed to water weight, I still see this as a significant weight loss result. I did previously try to look for a weight loss calculator that could give you an indication of what you should expect, however, I’ve honestly mostly been going off of my previous experiences, and how it affected my weight, and then extrapolating from there. I definitely found myself nice and slim after my last experience. Although there are reports out there of 90 day water fasts, as well as a man who fasted for 382 days, those are simply periods of time that would require putting on too much weight for me to ever dabble in those waters.

It is considered by many to be an extreme type of weight loss, which I can agree with. However, it doesn’t need to be too extreme and make you feel miserable. Following the proper steps and heeding precautions, you’ll definitely be able to go about it with ease. Sooner rather than later, you’ll get more and more confident about the whole experience! I’m actually planning on continuing with regular fasts, around twice to thrice a year from now on, as well as monthly 36 hour fasts, too. Do you want to join me on my monthly go at it? Make sure to read how over here.

Hope to see you around, no matter if your goal is 13 to 15 hours, or whether your goal is to go for 30 to 40 hours instead.

Leave a Comment

Your email address will not be published. Required fields are marked *