Three day water fast…
… and what it does for our body.
I decided not to eat anything for three days! If you had asked me a year ago about a three day fast, I would have answered NEVER! I would have given you a million reasons why! The real reason why I would not have done it, is that I would not have wanted to feel hellishly uncomfortable. I love food.
I love bread. The one that is soft on the inside and crunchy on the outside. I am a sucker for a coffee. My husband knows I get grumpy if I don’t have my cup of coffee. I like my avocado and poached egg on toast on Sunday mornings and could eat seafood pasta pretty much any day! And my biggest guilty pleasure is an occasional margherita pizza washed down with a diet coke. It is important to give ourselves a break occasionally.
Food and everything revolving around it, like getting ready for a nice meal in a restaurant, chatting with a friend in a coffee shop or just being alone, working with your laptop, surrounded by people, is an important part of daily life. Life would be less enjoyable without it. Then one day, I decided not to eat anything for three days!
How have I got here?
Except for feeling like a badass, for trying to do something that most would fail at, it is science that persuaded me to try it!
Science is clear about fasting. It is healthy for us. Various animal trials (mostly with mice and monkeys) have again and again proved that fasting makes us live longer. Just like in case of mice, we humans have developed to cope with prolonged amount of time without food, only drinking water.
Fasting has many benefits, even if we do it on a daily basis by limiting our eating window. In order to unleash the most important benefit of fasting, the autophagy, the extended fast are beneficial. In order to supercharge the autophagy process, we need approx. three days of fasting.
What happens when we do an extended fast?
When we start fasting, our body first burns carbohydrates (glycogen which is mostly stored in muscles, brain and liver). Carbohydrates are our default source of energy. After an extended fast, when body is deprived of carbohydrates, which normally happens at some point during second day of fasting, our body starts running out of carbohydrate storage.
At the point of carbohydrate deprivation, our body starts looking for a replacement source of energy, which is fat. In order to gain energy from fat, it switches to a stage called ketosis. During ketosis, fat is turned into ketones, an alternative source of energy.
What is autophagy
Autophagy is a state that body gets in if we don’t consume food. It is our natural defense mechanism, protecting our cells. It is always present in some form but it properly accelerates around the third day of fasting. When in a state of autophagy, our body starts breaking down damaged cells, which can be potentially be turning into cancer. It starts washing them out, via immune system and new healthy cells get produced.
Autophagy naturally decreases as we age. Fasting though may be a way of boosting it. It is a subject of cancer research, as furthering our understanding could potentially help develop new cancer treatments.
Autophagy and Alzheimer’s disease
Autophagy has been subject of a studies, focusing on furthering our understanding of the causes and treatments of Alzheimer’s disease and cognitive decline associated with aging in general. There is a connection between declining autophagy and development of neurodegenerative disorders, including Alzheimer’s disease. Autophagy plays a key role in metabolism of proteins connected to Alzheimer’s disease. (1)
Insulin sensitivity
When fasting, insulin production decreases, as the glycogen resources deplete. This increases insulin sensitivity, allowing the body to transport glucose from the bloodstream to cells more efficiently enabling the blood sugar level spikes to be managed better. This decreases chance of developing diabetes later in life.
Heart
When we fast, our LDL cholesterol (the bad cholesterol) and tryglyceride (blood fat connected to heart disease) decreases. This helps lower blood pressure and reduces chances of developing heart disease.
Inflammation
Inflammation is a normal part our immune system, it helps to fight infections. Nevertheless, a chronic inflammation is something that can have an impact on our long term health and is associated with the development of diseases, such as cancer or cardiovascular disease. Various studies looked at chronic inflammation and concluded that fasting can reduce it. This happens best when we enter the state of autophagy around third day of fasting.
Prolonged fasting also encourages white cell regeneration by clearing out old white blood cells and promoting new white cell production. These are essential in fighting disease.
Preparation for the fast
A little preparation when starting out, can go a long way. Some people might naturally find fasting not that challenging, whilst others might really struggle. I have struggled with fasting and started 16:8 fasts about 6 months ago. In the beginning, I could barely manage 12 hours but after a few failed attempts, I started getting better at it. I still fail quite often but my mindset has now shifted. I would not recommend trying to attempt a three day fast, without first experiencing shorter term fasts.
Mental preparation for an extended fast
Mental preparation for the fast is an important factor for its success. I set myself a date about a week before I started fasting and chose the days when I thought I could manage it best. It is important that you choose days that do not require much travel and when, perhaps you are less likely to meet people or go places with abundance of tempting food.
I had also ensured that we did not have any tempting food (mainly bread and cheese for me) in the kitchen during the fast. By preparing some meals for my daughter in the initial stages of the fast, when I was not really that hungry, I ensured that the food preparation did not bother me. I had the meals stored in the fridge and just warmed up what I needed and when I needed it for her.
It is easier to fast with someone. In my case I fasted with my husband, who found it vastly easier than myself and was there to encourage me when I felt a bit depleted.
Go light on carbs and coffee…
Prior to fasting, try to decrease the amount of carbohydrates in your diet. It helps you with managing the glucose levels and means that you achieve the desired ketosis sooner. If you eat carbs, focus on the complex ones such as whole grains, legumes, vegetables and fruits. Also, try to decrease amount of caffeine but noted that cutting it out for a while could cause headaches. Headaches have been my main problem during the fast, most of them have I suspect been due to me completely cutting out caffeine.
During the fast
Well…, it is very simple, no food and only drinks. I fasted only with water but some people fast with black coffee or tea. In order not to get dehydrated, you can add salt to your water a few times daily or get a rehydration powder that does not contain glucose. A rehydration powder will ensure you keep correct levels of sodium, calcium and potassium and magnesium amongst others. It might alleviate the leg cramps that both me and my husband experienced during the final stages of the fast. This is as exciting as it gets drink wise and food wise during fasting…
Day 1 of the fast
The first day felt for us mostly like a plain sailing. What really helped me was that we fasted together with my husband and could support each other throughout. We started the day by going to our favorite brunch place, where we ordered some eggs on toast with mushrooms, salmon and veggies, all dipped in a delicious pesto. It was a good sized meal and we had a great time as a family. I had my last coffee before the fast and ordered an oat milk cafe latte.
We started fasting exactly at 10am by going for a long walk in Porto. It was a hot spring day and a walk without our regular coffee shop breaks eventually got us ready to get the car and head home to spend the afternoon by the pool.
Around 3pm, whilst playing around the pool, I started to feel a bit of a hunger and really fancied some nice refreshing drink. After a while the feeling passed and I felt all right for the rest of the day. Nevertheless, it was just a beginning of a fast that we have never done before so in order not to get tempted by anything to eat at home, we decided to head to the beach for an evening walk.
Day 2 of the fast
When I woke up in the morning, I was very surprised how well I slept at night. The hunger was not any more profound than if I woke up on a normal day and I felt quite well, so I decided to go for a run after I dropped my daughter off at the nursery. Then I drove home and spent a few hours at the laptop, sipping more water than I would normally as I was not getting any liquids from food. Plus three times a day, I drank water with added salt so I avoid dehydration.
I started with a bad headache in the afternoon and I felt like it was the lack of caffeine causing it. I normally have three coffees per day. After a day without coffee, I was feeling it. In the evening, we went shopping and I was really surprised how my mind had shifted and how seeing the food around did not bother me at all. Yes, it would be nice to have but it was less of an issue than I had thought before I started fast.
During the afternoon, I started to feel much less alert and slow. I realized I needed to take it easy. I paused on my active lifestyle and chilled out by the TV for the rest of the day. Day two felt the hardest as I knew that there was still a long way to go.
Day 3 of the fast
Another great night sleep. I woke up reenergized and went to the bathroom to brush my teeth. Then all of a sudden I felt a bit dizzy and upset stomach. The feeling lasted for a couple of minutes, when I needed to sit down. It passed. A lot of people that do extended fasts might experience this feeling of weakness during fast. I decided to tackle it, by preparing a glass of water with salt straight away. It helped.
I then drove my daughter to the nursery and took the dog for a walk instead of my regular morning exercise. The tiredness was really profound at this point and it was all I could manage. Later on, things got better again and I drove home to spend a few hours at the laptop. Mid afternoon, I started to feel dizzy and had a double vision, due to a temporary decrease of blood pressure. Then things calmed down for a few hours.
During the third day I felt cold. I even had to put an extra layer of clothes whilst being at home. This happens because during fast, the digestion system runs out of food and instead of processing food, which creates heat, autophagy starts the process of cell repair. Ketosis also changes blood flow to promote fat as alternate source of energy. All this causes feeling of being cold.
Later in the evening, I started to feel extreme tiredness. I really needed to start preserving my energy. The night was not easy. I spent most of it awake. In the morning I was very much ready to break the fast.
Ketosis
I have collected and tested my urine sample at the end of the fast to validate if I reached ketosis:
Results
- Glucose (mmol/l): negative
- PH 60s: 6.5
- Protein 60s (g/l): Negative
- Ketone 40s (mmol/l): more than 16
- Blood 60s (ca cells/micro l): negative
Breaking the fast
In order to keep the ketosis going for as long as possible, even after we finish the fast, it is best to eat protein rich food in fairly small amounts. We have decided to first have a lemon tea to increase level of HCI and then a bit later, eat some scrambled eggs, seeded bread and a green smoothie (spinach, carrot, pear) for our first meal. I felt quite weak and ready to run on glucose again.
Most people that fast recommend a broth as a first meal. It contains plenty of liquid and salt for rehydration. It also has protein to keep the desired ketosis active a bit longer. For these reasons a broth would probably have been a better choice than the scrambled eggs, bread and smoothie that I chose but at this point, I was ready for some carbs!
One thing to remember is that the stomach shrinks during fasting, so our body will have less space for food. You really need to ensure you don’t overeat as that could make you quite unwell.
I was surprised that even though I enjoyed my first meal, it was not as satisfying as I thought it would be. More than enjoyment from the meal, I was looking forward to getting rid of all the fasting symptoms like tiredness, headaches and cold. Some people seem to experience ravenous hunger when they stop fasting. My stomach had shrunk so much that I did not actually enjoy the food itself as much as I thought.
Hydrochloric acid (HCI)
Hydrochloric acid (HCI) is important for our digestion. It activates enzymes that help digest proteins, fats and carbohydrates. Luckily there are couple natural remedies that help us break fast by boosting HCI levels. Such are apple cider vinegar, lemon and ginger. Just add water to it and drink before your meal when you stop fasting.
It is important to note that apple cider vinegar and lemon are acidic and would erode tooth enamel so best is to use a plenty of water to properly dilute them and use a few times to increase HCI levels and then to stop.
I decided not to eat for three days. What did my experience teach me?
Prior to staring the fast, I had doubted myself, thinking that I might not be able to achieve a three day fast. It was something very much out of my comfort zone. In the end, the fast was more manageable than I thought. Nevertheless, it is not an easy endeavor and it requires discipline. Extended fasting is a mind game full of ups and downs. Things can change from minute to minute.
Nevertheless, the feeling of accomplishment when you complete the fast is great. Not only I have done something amazing for my body and health but also I have proven to myself that I am stronger than I thought. After this experience, I feel mentally much better equipped to continue on my regular 16:8 fasts. If I have done three days, I feel I can do anything.
I have filmed my thoughts throughout the whole three days and will be sharing a video covering my fast on my YouTube channel in a couple of weeks! Stay tuned.
Let’s stay in touch!
Do you have any experience with prolonged fasting and how was it for you? Let us know your thoughts on Facebook, Instagram, LinkedIn or TikTok. Would you like to learn more about biohacking? Check out our article Is NMN answer to longevity in humans?
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Resources
Source: (1): Autophagy and Alzheimer’s Disease: From Molecular Mechanisms to Therapeutic Implications, PMCID: PMC5797541 / PMID: 29441009, Jan 30, 2018 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5797541/
