A guide to fasting


Reading time: 9 minutes

Welcome to my guide to fasting. Let's begin with a quote from the master faster, Mahatma Gandhi:

“Fasting is a feiry weapon. It has its own science. No one, as far as I’m aware, has perfect knowledge of it.”
— Gandhi


The information I present here is for information and education purposes. I assume no responsibility or liability for any consequence resulting directly or indirectly from any action or inaction you take based on the information contained in this article. For anyone with health challenges medical supervision is recommended.

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It's highly likely that you've heard about fasting before. You might have heard about juice fasts from the documentary Fat, Sick and Nearly Dead. Or popular intermittent fasting regimens like the 5:2 Diet. And I'm sure you'll all be aware of religious fasting. 

There are many benefits of fasting and there are also some dangers. For me, fasting is an incredible way to reset my eating habits and a great method to improve my health and longevity. 

Recently, I documented a 48-hour wilderness fast out in the Peak District National Park. Essentially I went off into the woods with my hammock and sleeping bag. I took no food with me and sat around playing with fire for the weekend!

During the last month, I have published several videos from my trip on the EVO•TEE YouTube channel. But for something as wide ranging as fasting, I thought it best to get my thoughts down into an article. I hope that this will support you in your own experimentation and exploration of fasting.

My brief fasting story

I first began experimenting with intermittent fasting in 2011. At the time I was playing a lot of rugby and wanted to get as lean as I could. I heard it was a good way to burn stubborn fat so I bought a few books and started experimenting.

Here's a brief guide to where I began:

  1. I would miss breakfast, eat lunch and dinner as normal
  2. Then I missed breakfast and lunch and ate two meals in the evening. One meal immediately after training and the second around 7/8pm
  3. Then I tried a 24 hour fast every Wednesday

At the time, in my quest to get big and strong, I was eating all the time. So the thought of not eating was intimidating. But like most things, once I committed to it, it was much easier than I had thought.

From there I went on to experiment with longer fasts (three and four days). That was much harder but also much more rewarding. Today my fasting is more sporadic. Throughout the week I will often eat only eat in the evening, but some days I'll eat lunch and some weekend days I'll have three meals spread throughout the day.

I have found that intermittent fasting has little or no effect on my energy levels and I am quite happy to do hard manual labour for a day without the need to eat. 

In the last year or two, I have also enjoyed some wilderness fasting. A wilderness fast is just fasting in nature. While this requires a little more planning, I have found it to be much more beneficial on a psychological, emotional and spiritual level.

A friend introduced me to an incredible author called Stephen Harrod Buhner. I checked out a few of his interviews and was inspired by him so much that I've bought several of his books. The first was:


  Here's a section taken from his book that expands on my initial descriptions of fasting:

“In going into the wilderness to fast, human beings encounter the true essentials of life; they strip from themselves the daily concerns that occupy so much of their time. Our daily concerns normally occupy so much time that we often begin to think they are all there is.
So this time away, in the original wildness of the world, allows us, for a while, to walk away from the ordinary world and begin to focus on the deeper and more important truths of our souls.”
— Stephen Harrod Buhner

Do you use food or does food use you?

Like many people I don't always have the best relationship with food. There are times where something else takes over my hands and mouth and they force me to eat all sorts of processed treats!

Why I fast?

Fasting puts me back into a healthier relationship with food. After a fast, I feel so much better, physically, mentally and emotionally. From my own research, it is clear there are many physical benefits of fasting. Many of these benefits increase longevity and human health span. 

If you want to learn the metabolic benefits of fasting, I would recommend the following interview. Here Dr Rhonda Patrick interviews Ray Cronise after a 21 day fast!

Dr Rhonda Patrick has also interviewed other experts on fasting such as Dr Valter Longo and Dr Satchin Panda.

The Challenges of Fasting

Fasting for one or two days is unlikely to cause any significant problems. The body has evolved over millions of years to survive temporary shortages of food. That said, for anyone with specific health challenges medical supervision is always recommended.

Fasting poses a set of physical, emotional, and spiritual challenges. Fasting tests our will because it can be uncomfortable and side effects are common.

What follows is a list of side effects that I share with you not to put you off, but to be honest. Of course, it is unlikely you will suffer from all of these side effects simultaneously:

  • dizziness
  • confusion
  • cold extremities
  • weakness
  • nausea
  • vomiting
  • headaches
  • strong urine colour and odour
  • strong body odour
  • metallic taste in the mouth
  • weak pulse
  • joint, bone or other abdominal pain
  • hunger
  • diarrhoea
  • lack of bowel movements
  • lack of desire to sleep
  • waking in the middle of the night
  • emotional distress

Living in a toxic world

These side effects are due to living in a toxic world. During the course of a lifetime, we come across many environmental toxins that are hidden to our senses. The primary sources of toxins are:

  1. airborne pollution that we breathe in or absorb through our skin
  2. pollutants that we ingest, that are on or in our foods
  3. pharmaceuticals and 
  4. toxins from bacteria and viruses that are inside our body.

In billions of years of evolution, organisms have never come across so many toxins. The detoxification organs cannot always process toxins. When we cannot eliminate toxins, they end up hidden around the body, absorbed by fat cells. Fat is such a good insulator that it protects the cells from the harmful effects of most toxins

The so-called 'experts' (often employed by the world's most powerful companies) tell us that toxins are harmless in small dosages. Unfortunately, this is not always true and they have an accumulative effect. There is scant research on how toxins might interact with each other in the body.

What happens when we fast?

When fasting the body begins a spring cleaning process called autophagy or autophagocytosis. In Greek, this means self-consuming/ devouring. The body is in constant flux, cells are dying and being reborn all the time. The body you have now is not the body you will have in ten years time. Just look at this table below:

Photo credit: Cell Biology by Numbers

Photo credit: Cell Biology by Numbers

After ten hours of fasting, the body ramps up cell autophagy. After 10 hours of nil by mouth, the body uses stored fat as a primary fuel. What happens when we burn fat that contains stored toxins? Yep, you guessed right, those toxins get released and then need processing.

In a healthy body toxins get eliminated, but after years of toxic overload, our detoxification organs get compromised. Toxins can circulate around the body causing damage. This is one of the reasons why fasting can so be challenging.

It is well established that environmental toxins such as lead, mercury and PCB's end up in the brain and nervous system. The presence of these neurotoxins can cause disabilities, birth defects and learning difficulties.

Whilst fasting, the body has a surplus of energy that normally supports digestion. Like when we're sleeping, energy is used to detoxify, regenerate and repair. During a prolonged fast, the body consumes anything that is not essential. This includes bacteria, viruses, fibroid tumours and metabolic waste products.

If we never fast we rely on detoxification to occur when our head hits the pillow. Regenerative sleep is a bit of premium these days. In the past when we were connected to natural cycles of the sun, sleep was much more regenerative. Spending all day inside buildings under artificial light, surrounded by electromagnetic radiation suppresses melatonin. Melatonin is not only the hormone that puts us to sleep, it is one the most powerful antioxidants the body produces.

Premature ageing

Deep fasting allows the body to focus solely on detoxification, repair and regeneration.  Scientists such as Aubrey de Grey, have popularised the causes of ageing and death. Just by being alive, we cause damage to the body.

Aubrey de Grey the ageing wizard! Photo credit: Flickr

Aubrey de Grey the ageing wizard!

Photo credit: Flickr

We also accumulate waste products and cells become dysfunctional. At some point in our life, we can no longer keep up with the damaging effects of being alive and we die! As we age, we get more and more behind with the task of repair, regeneration and waste removal. Healthier and longer lived humans are just better at:

  1. Repairing and regeneration
  2. Reducing the rate of damage

Spend a few years burning the candle at both ends, drinking, smoking and drug-taking and we speed up ageing. Spend a few months in Goa on a yoga retreat and we can slow it down. Fasting is just a way of supporting the body to perform spring cleaning tasks.

So if you're scared of getting old and wrinkly, perhaps a little fasting might be the best thing for you.

Photo Credit: Pixabay

Photo Credit: Pixabay

Beyond 24-48 hour fasts

Longer water fasts are a genuine challenge. I remember my first four-day fast, all I could do was sit around the house. But somewhere between three and seven days, life gets easier. Eventually, we make energy more efficiently from reserves of body fat, a process called ketosis. Ketones are a glucose alternative that the body thrives on.

Following a ketogenic, or high-fat diet, will make your life easier before going nil by mouth. Ketogenic supplements are now formulated to make life easier. Scientist, Dom D'Agostino, has demonstrated that ketogenic diets are effective at starving cancer and treating epilepsy.

In evolutionary terms, the body and mind have to be at their best when going without food. If our bodies didn't thrive on ketones how would we have survived through the tough times prior to supermarkets?!

Ketosis versus starving

Stephen Harrod Buhner, who has supervised thousands of fasts, suggests that even thin individuals have enough reserves to fast at least 45 days and often longer. Starvation only occurs when the fat stores run out and the body begins to use protein as a fuel. This can occur between 45 and 120 days. 

A quick Google search revealed a study from 1973 where a 27 years old male fasted for 382 days under the supervision of medical researchers in Scotland.

  Please take care if you are fasting for longer periods of time, again this is not something to be taken lightly.


Please take care if you are fasting for longer periods of time, again this is not something to be taken lightly.

Hit the reset button

I fast for a physical and mental reset. The shift to ketosis causes many alterations in the functioning of our physiology that would never occur through dieting. The body has a kind of food thermostat that changes to a lower setting after a fast. There's even a drop in glucose tolerance, meaning it takes less sugar to satisfy you.

Fasting also increases our sensitivity to the needs of the body. You'll no longer want many of the processed foods that we so often crave (although this will eventually go away). Stephen Harrod Buhner suggests this comes from a re-tuning of the vomeronasal organ (VSO). The VSO or the Jacobson's organ is an auxiliary olfactory sense organ, which identifies substances entering into the body.

Leptin, is another hormone that is reset by fasting. Leptin is also known as the obese gene because of its correlation with obesity. It plays a major role in hunger and energy expenditure and affects how we convert carbohydrates into fat.

Insulin sensitivity has also been found to increase. Insulin is the fat storing hormone. When blood sugar rises, insulin is released, funnelling sugar in fat and muscle cells. If we're inactive desk jockeys, then our muscles won't need the sugar and it will be shuttled straight into the cells of our love handles.

Other benefits

I'd say there are two kinds of people in this world:

  1. Those who eat to live - the pragmatists
  2. Those who live to eat - the pleasure seekers

I am the kind of person who lives to eat, I think about food all the time. Unless I'm preoccupied with a purposeful task, I'm thinking about food. And when I fast something miraculous happens - I no longer think about food all the time. My mental focus goes through the roof because I'm not preoccupied with food thoughts. 

Many people live or work in environments where they are faced with constant temptation. But when you make the decision to fast, life becomes simple.  Eat or don't eat. Continue the fast or break the fast.

A word on breaking a fast

The longer a fast, the more care we need to take to break the fast. Enzymes and bacteria play a huge role in digestion. After a considerable period of time fasting enzyme production is reduced and bacteria go to sleep. So we should always break a fast with simple vegetarian food, something like a vegetable juice or soup.

That said, after my first three day fast, I refuelled with steak and vegetables and to be honest I felt like superman. The surge of energy I experienced was incredible. In the end, I had to go for a run and when I did, what happened was remarkable. I ran like a man possessed. When I run, I'm usually battling negative thoughts in my head, but this time I just wanted to run faster and faster. I knocked about 15 minutes off my normal 45-minute circuit! (I also felt really really horny, sorry!)  

Male v Female fasting 

In case you haven't noticed, I am a man. As hunter-gatherers, men hunted more than women. Men left the camp for days on end in search of food. They also lead battles against other tribes and explored new territory. For a tribe to survive, women had to ensure the survival of their offspring. As a result, women evolved physically and mentally to be better at gathering and foraging than hunting. That doesn't mean women can't hunt and men can't forage it's just a generalisation.

This would suggest why women don't always respond as well to intermittent fasting as men do. Precise Nutrition (link) put together an excellent resource that I recommend all women to read. But please don't let this put you of fasting altogether.  Intermittent fasting and periodic fasting are two separate tools. A periodic fast would be just as beneficial to a woman's health as to a man's. For example, you may choose to fast for 3 days once a year. Or fast for twenty-one days every three years.

A fast conclusion

I discovered fasting out of a desire to burn fat. But what I have discovered is that fasting is a much more versatile tool to have in the health and well-being locker. Short fasts can boost productivity and energy. Longer fasts can help fight disease and support health and longevity. Wilderness fasting supports emotional and spiritual transformations. And a blend of all of them can support us in becoming the strongest version of ourselves on a physical, emotional and spiritual level.

I'll finish with this meaningful quote: 

“The truth is that your body, every ounce of fat you carry, is not your enemy. It is part of you, a part that has been shamed by in a culture obsessed with thinness.”
— Carol Normandi and Laurelee Roark

This ain't normal and is not what we should be aiming for!

Below is the playlist from the Words from the Woods series. Enjoy

James @