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5 Days With No Food

Empty plate and cutlery

How interesting does not eating for a whole 5 days sound? At first your probably think "hell no, how could anyone do that?" Surely death would happen pretty damn quick without food.

Fasting has been around since the beginning of time, and is a great way to kickstart your metabolism, lose body fat, reverse diabetes and much more.

There is a long list of benefits to fasting such as:

  • Weight loss  
  • Increase in Growth Hormone  
  • Lower insulin sensitivity  
  • Speeds up metabolism  
  • Promotes longevity  
  • Improves hunger control  
  • Improves brain function (mental clarity)  
  • Improves your immune system  
  • Helps to clear the skin and clear acne

Fasting is something I have wanted to try for a while and I recently got the chance with a little break in my training. I wanted to try something challenging to really test my boundaries and see what kind of results I would get. I have been intermittent fasting for about 4 years now doing a 16/8 daily fast. This means I fast for 16 hours and have an 8 hour window to eat during the day. My day usually starts at 5:00am with a black or bulletproof coffee, then I will have my breakfast at 12:00pm.  From 12:00pm until 8:00pm I will fit in all my calories that I need throughout the day. Once 8:00pm hits, I only consume water or tea until bed time. This wasn't really that hard to get used to, and really helped me to decrease my body fat percentage when I wanted to. Something like this is a great tool you can utilise when you have a wedding, reunion or beach day, that you want to look awesome for.

After listening to a podcast all about fasting it re-sparked my interest in a longer fast. Ben Greenfield interviews Dr. Fung in his podcast show and walks you through the process and the benefits of fasting. He actually talks about a study that was done where a male did a 382 day fast - no food for that long is crazy, but possible. He lost 276 pounds and 5 years later kept all the weight off. This is proof that the fat loss stays off and doesn't come back like these fad diets that most people are trying. Dr. Mercola also talks with Dr. Fung on the topic of fasting, and gives some great tips and advice in this article.


What Happens to Your Body During The Fasting Period?

From 0 to around 24 hours your insulin starts to fall. Once the food that you eat is gone, you need to start pulling out energy back out from the body in order to keep working. The first place your body goes for this energy is glucose, and for up to about 24 hours.

After around 24 hours the glycogen stores run out and there is a period of gluconeogensis. This is the breakdown of protein to create glucose in order to feed the cells. This continues until about 36 hours then fat oxidation starts to take over, you see fatty acid levels go up in the blood, and you see fat in the blood. Basically your body starts living off of stored fat from about 36 hours on, putting you into ketosis. As you get more and more into your fast your body gets better at metabolising fat giving you mental clarity and normal energy levels with no crashing throughout the day.

When we had to hunt for our food we certainly didn't have the convenience of being able to eat 3-5 meals a day with a quality source of protein. If we missed a meal and just continued to lose energy until we got to the point where we couldn't hunt then we would just starve. Instead our body finds its own fuel within to give us the power and energy we need to survive and hunt if need be.

I was a little impatient and just started the fast without getting enough research. I would have had around 6-7% body fat which left me feeling tired and lethargic when my body entered into ketosis on day 3. 48 hours was my real high, I had a lot of energy and felt amazing. After that everything got really hard and I could not maintain the fast, I knew it didn't feel right when I wasn't getting the benefits I had been reading about. I broke the fast 86 hours in on the morning of day 4, I woke up and knew something wasn't right. I still wasn't hungry but my mood and energy was non existent, I could tell that my body didn't have enough fat to sustain a ketogenic diet with no intake.

Next time I do an extended fast past 48 hours I will have a doctor monitor my body and make sure things are going correctly. I made some mistakes going into this 5 days fast and wish I did some more research. Before you decide to do anything like this consult your doctor and do the research and get any questions you might have answered.

Here is my raw notes from the fast.

5 day fast


  • Last meal, protein shake with collagen at 10:22pm  
  • Weight = 72.3kg

Day 1 Monday

  • 2:00pm - I really want to eat, water isn't doing it for me. I'm going to make some tea.  
  • 4:00pm - headache  
  • Weight = 71.4kg  
  • 10:00pm - 24 hours in and feel ok. Not hungry but feel like eating something

Day 2 Tuesday

  • 5:00am - tired and headache is still there. Drinking water helps me feel better, don't really feel hungry.  
  • 3:00pm- Feels really weird not eating. Mentally it's harder to not eat something when bored. I feel like I have so much time on my hands to do everything. All I'm thinking about now is getting stuff done. Starting to realise how much time is spent eating during the day.  
  • 4:30pm - had some electrolytes because I feel like eating something. Felt good to have some flavour but I don't think it made a difference

Day 3 Wednesday

  • 3:00am - Woke up really hungry  
  • 6:00am - Really tired and feeling drained  
  • 5:45pm - Not feeling it today, really want to give in and just eat some food. Mixed up some BCAA's to make me feel better  
  • 9:45pm - Having a really tough time today with energy and mentally pushing through, don't know if it's worth it at the moment

Day 4 Thursday

  • 6:30am - Had a really vivid dream of eating last night, woke up and thought I broke the fast but quickly realised it was a dream. Feel pretty damn slow, I'm not feeling that great and  really considering eating today. Mentally I feel pretty good but energy wise I feel nothing. I'm starting to think my body fat was too low to begin with for this experiment.  
  • 8:00am - Couldn't do it anymore broke the fast with a small amount of peanuts, because that's all I could find  
  • Weight = 69kg  
  • 10:00am - Picked up some sauerkraut to eat to put some good bacteria into the gut after not eating for so long. Then had 2 eggs, halloumi, sourdough bread with avocado. Energy levels still took a while to come back  
  • 4:30pm - Tried to have a workout, mentally felt really good but when I tried to do some thrusters and burpees I had nothing at all. Was instantly out of breath and could not push.  
  • 6:30pm - Weight = 69.5kg  
  • 7:00pm - ZUU class - had a really hard time getting through the class, still no energy.

Day 5 Friday

  • 12:00pm - Starting to feel better, went for a 10 km easy run and was able to push the last 4 km hard.  
  • Weight 71.5kg

Left – Day 1, 72.3 kg                                                 Right – Day 4, 69kg

In conclusion I should have been consuming some fat in a bulletproof coffee and maybe some coconut oil. I'm still unsure of what I should have been taking throughout this fast to gain the benefits I was after. I would definitely speak with a doctor before doing this again to make sure everything goes right.

Thanks and let me know how you go with your fasting experience, or if you have any questions or comments.

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