What to Expect on a 5 Day Water Fast
Water fasting is one of the most ancient and powerful healing strategies known to mankind. Modern science is showing the profound benefits of water fasting on reducing inflammation, stimulating cellular cleansing called autophagy and producing stem cells to regenerate new tissue. In this article, I will let the reader know what to expect as they go through a 5 day water fast.
Fasting is like exercise in that it is very uncomfortable and can even be downright painful when you first get started. But just like exercise, as you develop your fasting fitness, it will get easier and more enjoyable.
Most people are highly concerned about what they may experience on an extended water fast and rightfully so. My purpose in writing this is to go through day to day what you can expect as you navigate the journey on a water fast.
The Transformational Benefits of Fasting
I am a huge fan of both extended and intermittent fasting strategies. The main benefits you get from an extended fast that go beyond what you get with intermittent fasting or time restricted feeding include greater levels of autophagy and human growth hormone release and increases in stem cells within all the tissues of the body (1, 2, 3, 4).
While intermittent fasting is a very powerful healing tool, extended fasting allows the body to heal and repair older cells, tissues and organs at a much higher level. If you are younger and very healthy than you may get all the benefits you need from intermittent fasting. However, if you have health challenges or want to do all you can to prevent them than I think extended water fasting is one of the very best things you can do.
I believe that most everyone can benefit from one or two extended fasts each year to cleanse the body of all the older, weaker cellular components and rebuild a new cellular structure.
Those who stand to benefit the most from extended water fasting include individuals suffering from the following:
Metabolic Syndrome – Diabetes and Obesity
Chronic Inflammatory Conditions
Gut Health Challenges
If you want to learn about all the great benefits of living a fasting lifestyle where you practice intermittent fasting and possibly some occasional extended fasts you can read about it in this article.
Who Shouldn’t Fast:
While most people stand to benefit from extended water fasting from time to time, there are certain individuals I would not recommend this too. This would include the following:
Nursing Moms and Newborns
Individuals with Type I Diabetes
Individuals with Eating Disorders
Extreme Athletes Who are in Season
Individuals Who Are Severely Underweight
Individuals Who Are on Medications (Especially diabetes medication, anti-seizure meds and corticosteroids as these can impact blood sugar levels). These people may still be able to fast but should consult with their doctor first.
*Always check in with your doctor before stopping any medication. Some medications may still be needed, such as thyroid medications. These are okay to continue to take while fasting. With may find you need to take less of some medications. Always consult with your Doctor before changing doses or stopping a medication.
Preparing Your Body Ahead of Time:
I find that building your fasting fitness through intermittent fasting is one of the best daily activities you can do to improve your health and then periodically undergoing an extended water fast is a fantastic health improvement and maintenance approach to take into life.
There can be a lot of discomfort when you first begin fasting as your body has to make a lot of metabolic adaptations and we are so emotionally and neurologically driven to feed. Many people have physical and emotional addictions to food and this can be very challenging to deal with in the early phases of fasting.
There are certain things you should do to prepare your mind and body for the fast so you can have the best experience possible. You can read about those things in the graphic below and in more detail in this article.
What to Expect on a 5 Day Water Fast
Fasting is just as natural for our body as feeding is. Our ancestors have been going without food for days at a time quite often. The level of food abundance we have today is a great benefit but at what cost?
In fact, when we eat food, we actually expose our body to a tremendous stress. Food contains microbes on it, some good and some bad, that will impact our microbiome. It also contains plant or animal material that is stressful on our digestive system and depends upon the proper production and release of digestive juices to metabolize correctly.
In general, we don’t see feeding as a stress on the body, because we are so used to doing it. It is obviously a necessary stress in that we cannot survive without it.
When we begin to fast, there are many positive changes that occur, but also some unwanted symptoms that we will experience. This is all normal and natural and in this article, I will go through these so you can better understand what your body is experiencing.
Unless you are already keto adapted going into the fast, day one your body is primarily using stored sugar, called glycogen, as its fuel source. We store roughly 500 grams of this glycogen in our muscles (400 grams) and liver (100 grams).
Some people such as athletes and highly active individuals store more than those who are less active. 500 grams of stored sugar equates to roughly 2000 calories. The body will not use 100% of this as it will save a small percentage for later but roughly 70% or so is used up in the first day or two.
In addition, the body will begin to burn body fat. If you are keto adapted, you will see a nice rise in your ketones toward the later half of the first day. If you are not keto adapted, you will not have a significant level of blood ketones but will begin to urinate out ketones toward the end of the first day.
If you are keto adapted and have been practicing intermittent fasting than your body will begin to ramp up higher levels of autophagy and cellular cleansing in the last 4 -8 hours of the day.
Day 1 Symptoms:
All of these symptoms are normal and not be concerned about.
Fatigue: This is because the body is not well adapted to burning fat and ketones for fuel. Because I practice a full 24 hour fast, 2 times each week myself, I actually feel quite energized on Day 1 of a longer fast.
Mental Lethargy: We are so used to our brain having a steady sugar supply to fuel it and now that sugar supply is lower so we produce less brain energy. In addition, food stimulates neurotransmitter production and so our levels are now reduced. If you are keto adapted to begin with, you most likely won’t notice much mental lethargy on Day 1.
Hunger: This is due to the hormone ghrelin, which is secreted by our stomach in response to the stomach being empty or as a conditioned response at times of the day when we are used to feeding. Don’t worry, you are not starving or at risk of dying…you are simply responding to your body’s natural hormonal pattern.
Cravings: Cravings are a brain-based response to an emotional desire. When we eat, we stimulate a flood of feel good neurotransmitters in our brain such as dopamine and serotonin. This is a great thing and it is very pleasurable to eat. When we fast, if our brain is overly used too or reliant on this flood of emotions…it will send an increase in signals to fill this desire.
Mood Changes: As the body is adapting to burning fat instead of sugar, the brain will experience periods of hypoglycemia and this can lead to brain fog, mental lethargy, depression and irritability. You may also experience headaches.
Increased Urination: When the body breaks down glycogen for fuel, it also releases more water into the urinary system. Having to urinate more often is a normal and natural response. You should also be drinking more water than normal, which will also increase the amount you pee!
Sleep Disturbances: Some people sleep their best throughout the fast, while others have a harder time. The more keto adapted you are to begin with the less hypoglycemia you will experience and you will typically notice better sleep. Using some extra magnesium, L-theanine, melatonin and adaptogenic herbs such as ashwaghanda can be very helpful to improve your sleep if needed. You can check out this article for more details on that.
As you move into Day 2, you will continue to experience all of the symptoms from Day 1 although your hunger levels are typically beginning to diminish.
For someone that is keto adapted and used to daily intermittent fasting, Day 2 is usually the toughest. I have no problems at all doing the first 24 hour fast but as I get into day 2, I feel more fatigued.
Day 2 Symptoms
On Day 2, we will experience more of what we experienced on Day 1 and possibly an increase in the fatigue, brain fog and mood changes. As I said above, Day 2 is typically the most challenging day. Here are some additional unpleasantries you may experience:
Tongue Changes: Your tongue may turn white, yellow or even black. This is a part of the normal detoxification response of the body.
Rashes: It is possible to have rashes although rare, these occur in about 10% or so of the population. The rashes have to do with a resetting of the microbiome. There is a communication between the gut microbiome and the skin microbiome.
Fasting starves down the biome and many toxic substances are released into circulation that trigger histamine and substance P in the skin that cause skin inflammation and rashes. These will go away over time and are typically a sign of a healing response.
Feeling Cold: When your body senses that you are in a time of famine, such as going multiple days without food, it will begin to downregulate active thyroid hormone. This is done in order to help improve energy efficiency in the body. One of the more common early symptoms here is having cold hands and feet and feeling colder in general.
Don’t worry however, as the process of fasting helps to reset hormone sensitivity and optimize hormone expression in the body. This will lead to the body not needing as much thyroid hormone, insulin, etc. in order to function well. This is a very positive adaptation.
Healing Activity on Day 2:
Here are some of the really cool things that ramp up on Day 2 of the fast. You get these on Day 1 but in smaller amounts and each successive day up until Day 5, the levels continue to increase.
- Resets the Microbiome: Fasting helps to de-weed the gut flora and pulls out a lot of good and bad microbes (5). This is a really good thing as the food abundance we have in our society favors the development of a lot of bad gut microbes.
- Cellular Autophagy: The body gets to work on intracellular cleansing, breaking down older, weaker cells and cellular components such as mitochondria and using the raw materials to rebuild new cells (6).
- Rise in Human Growth Hormone: Human growth hormone (HGH) goes up significantly in order to help preserve our muscle mass. This also helps to improve immune function, bone tissue and fat burning.
- Stem Cell Rise: The body creates new white blood cells, repairs the intestinal membrane and increases new and youthful stem cells in joints and tissues that have suffered through damage and need repair (7).
- Resets the DNA: We all have certain “bad” genes turned on that amplify inflammation and lead us down a road to chronic degeneration. Some of these genes promote things like obesity, allergies, autoimmune conditions, etc. Fasting turns these genes off like flicking a light switch off so they go dormant (1). Depending upon how many of these genes you have turned on, you may need repeated fasts or yearly/biyearly fasts to turn them all off or keep them off.
- Hormone Optimization: There are many hormones in the body including thyroid hormone, insulin, estrogen, testosterone and more. These hormones play a vital role in every function but they are dependent upon the sensitivity of the hormone receptors on the cells. This is like having the right key to open the door and enter the cell.
Fasting helps the body get rid of defective hormone receptors and rebuild strong and healthy hormone receptors. When this happens, we need less hormone circulating to have the desired effect. This is the essence of hormone optimization…and ideal communication between the hormonal systems and the cells of the body.
On day 3 you will have a very large rise in ketones and many people feel better mentally as the brain loves using these ketones for energy. If you were not keto adapted before the fast, it will probably take a bit longer for your brain to adapt and so you may not feel good.
If this is the case, you will probably experience more of the symptoms listed above. I typically feel good by Day 3 but have some bouts of tiredness and brain fog throughout the day. Definitely better than Day 3 but not as sharp as Day 4.
Healing Activity on Day 3:
You can further rise in autophagy, HGH and stem cells. The body is kicking up the healing activity and you may notice areas of pain reducing. On Day 3 and into Day 4 we experience the hormone optimization and will have great bouts of energy and mental clarity.
If you are still struggling on Day 3, hang in there as it should get better by Day 4. One great thing to track to give you more clarity on how you are adapting to the fast is your blood ketones.
Urine ketones will typically be high on Day 1 and 2 but should drop on Day 3 as your body gets more efficiently adapted at using these for energy. So, it is best to test with either breath or blood ketones.
Ketones in the blood will often rise up in the beginning and then drop back some as the body is using these as the main energy source by Day 3. Breath ketones are a great measure as they are showing the breath acetone which is a reflection of the ketones your body is using for energy. In this article here, I go over how to test your level of ketones.
Glucose to Ketone Ratio
The Glucose Ketone Index, or the GKI, is a ratio that researcher Dr. Thomas Seyfried has been using in his studies looking at tumors and how they respond to both fasting and the ketogenic diet (8). A healthy nutritional ketosis marker for the GKI is between 1:1 and 4:1. If you are in this zone, you are in nutritional ketosis and your body is either learning how to use ketones for energy or has adapted and is using them as a primary energy source.
However, when it comes to brain tumors and other cancers, Dr Seyfriend and his colleagues have found a ratio close to 1:1 to be most effective. The target zone for this is when the glucose numbers are in the 60’s and the ketones are roughly 3.0 mmol/L or more. You can get to these levels through the water fast and typically by Day 4-5, most people will be hovering in this range.
The GKI is found by taking the blood glucose level and dividing it by 18. You then take that number and divide it by the blood ketone level. A blood sugar of 64 with ketone level of 3.1 would have a GKI of 1.15
GKI: (64/18) / 3.1 = 1.15
According to Dr Seyfried, a GKI of 1:1 is the most effective level for shrinking tumors. This is due to the rampant amount of autophagy that takes place and the lack of insulin and available glucose that tumor cells use to grow and divide. If you are hitting close to a 1:1 GKI than the body is going to work on these destructive cells.
Your blood glucose will typically be at its highest in the morning due to higher cortisol levels but should drop as the day goes on. Stress will cause it to go up higher so do your best to limit the amount of stress you are under.
As you head into Day 4 and 5, you should begin to see the GKI trending towards 1:1. Autophagy is ramping up and you should have forced enough adaptation to where your brain is being fueled on ketones and feels alive and well.
On day 4, I feel so energized and mentally sharp that I am at my most productive level. The majority of people experience great physical energy and mental clarity. At this point, you should have no hunger or strong cravings but you may have just a slight emotional desire to eat.
There are a few things that can throw off your GKI and cause you to feel unwell at this point in the fast. These include stress, constipation and high levels of toxicity in the body. It can be helpful to use supplements and preparation steps if you are concerned about this.
Supplements to Support the Body
High stress can be balanced with Cortisol Defense and the unsweetened version of the Brain Calm Magnesium. If for some reason, your body has had a lot of trouble producing ketones due to stress and metabolic damage than using the Keto Edge would be really key.
For constipation, I use the Oxy Powder to flush the system and cleanse the bowels. You will need to drink a good amount of water and replenish minerals by taking a small pinch of salt two to three times a day.
For systemic toxins in the blood stream, I use the BioToxin Binder to bind and move these out of the body. The oxidative stress that toxins can cause will be neutralized by molecular hydrogen or glutathione. I like the Echo H2 drops or Super Glutathione. The combination of these supplements can help you get the most cleansing and comfortable experience on your fast.
The Fasting Stress Support Pack
To try to simplify things, I have created 2 unique fasting support packs. The Fasting Stress Support pack includes the Keto Edge, Cortisol Defense and Brain Calm Magnesium. This is great for those who are new to fasting and individuals who struggle with high cortisol and hypoglycemia when they fast.
The recommendations for this are to take 1 scoop of the Keto Edge in water during the challenging phases of your fast when you begin to feel the symptoms coming on. I also recommend doing 1 cap of the Cortisol Defense in the morning, at mid-day or early afternoon and 1-2 capsules before bed to help improve sleep quality.
The Brain Calm magnesium unsweetened powder can be used along with the Keto Edge and also taken before bed to improve sleep quality. As an added bonus, the magnesium will also help with bowel motility.
We priced this pack out in order to provide over 25% savings off of the regular retail rate.
The Fasting Detox Pack
This product pack is exceptional for helping improve bowel motility and colon cleansing while binding to endotoxic debris that is in circulation. The molecular hydrogen protects the cells, mitochondria and DNA from oxidative stress and supports the process of autophagy for optimal cellular cleansing.
We priced this pack out in order to provide over 20% savings off of the regular retail rate.
When Should You Stop the Fast?
At Day 4, your body should be thriving and it is typically quite easy to keep the fast going for the 5th and final day. However, some individuals who have significant metabolic dysfunction or excessive stress may have some issues and need to stop early. Here are warning signs to look out for
Strong Hunger: You may have a slight desire to eat but should not experience real hunger. If you do, you may want to listen to your body and break your fast.
Heart Palpitations: If you are noticing heart palpitations that are scaring you or causing you not to sleep, it is best to break the fast.
Increased Hair Loss: If you notice hair falling out in clumps than it is time to stop the fast.
Losing Consciousness and Passing Out: If you lose consciousness and pass out and feel extremely dizzy than it is time to stop the fast.
Extreme Pain: If you are in unbearable pain during the fast, then it is time to stop the fast.
Heavy Bouts of Diarrhea or Vomiting: This could cause you to lose too many electrolytes, you will need to break the fast.
Too Much Weight Loss: If you look and feel emaciated and weak, than go ahead and break the fast.
There is no shame in stopping the fast early. Our body gets stronger and healthier with each successive fast. If you have major health challenges, than you should be doing a water fast every 1-3 months and over time you will have less of these problematic symptoms and be able to do the full 5 days.
Day 5 is when your body gets the largest rise in HGH and Stem Cells. You get tremendous amounts of autophagy and hormone optimization. When you consume food at the end of Day 5, you feed the stem cells and replenish the bodies white blood cells.
You should feel fantastic today although you may see your blood ketones slightly drop as your body is getting better and better at using them for energy.
Fasting for longer than 5 days can have continued benefits but after 5 days you risk losing lean body mass. For lean individuals like myself, I stay at 4-5 days.
If you are looking to lose more weight than extending the fast can be extremely beneficial as long as you are feeling okay. In addition, if you have a chronic inflammatory condition and you are feeling better at Day 5 than you can consider continuing the fast.
People have successfully done 40+ day water fasts without any issues. This doesn’t mean you have too but fasting like this can be safe and beneficial in certain circumstances.
How Often Should I Do an Extended Fast?
I believe that for many people a 4-5 day water fast is all that is needed. If you are significantly overweight or have debilitating inflammation, you may consider doing a longer fast such as 8-10 days or you can just do the 4-5 day fast more frequently.
For lean individuals with chronic inflammatory diseases, I will typically recommend a 3-5 day water fast every 8-12 weeks until the inflammatory condition improves. Your body will get stronger and healthier through each fast. Over the course of 6-8 months, you can see dramatic improvements by doing these periodic extended fasts.
For individuals with a lot of weight to lose, I will often recommend a 10-day water fast every other month or a 5-day water fast each month. This is a great regimen to follow along with daily intermittent fasting or alternative day fasting to see significant weight loss and dramatic improvements in insulin sensitivity and inflammation levels.
How to Break the Fast:
My general rule on breaking an extended water fast is to add up the amount of days you fasted and divide by 2. Give yourself that many days before adding back harder to digest foods such as raw veggies, meat and eggs.
The first meal when you break your fast should be a protein shake with high quality ingredients, possibly bone broth or vegetable broth and a fermented drink like coconut water kefir. Here is a helpful infographic to guide you.
Sources For This Article Include:
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3. Cheng CW, Adams GB, Perin L, et al. Prolonged fasting reduces IGF-1/PKA to promote hematopoietic-stem-cell-based regeneration and reverse immunosuppression. Cell Stem Cell. 2014; 14(6):810-23. PMCID: 4102383
4. Mendelsohn AR and Larrik JW. Prolonged fasting/refeeding promotes hematopietic stem cell regeneration and rejuvenation. Rejuvenation Res. 2014 Aug; 17(4): 385-9. PMID: 25072352
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