Throughout history, there’s been instances of people surviving for several days without food. Fasting has been a part of religious rituals, political protests and medical/scientific practices. Soldiers in the world war era fought for days and  even weeks under extreme battle conditions without food, water and sleep.

That made me curious to know about how long can we humans actually survive without food. 

Most research points out that we can survive up to 21 days without food. However, the longest recorded fast lasted 382 days!!!

“In general, the human body can survive for 3 minutes without air: 3 days without water: 3 weeks without food” – Lofty Wiseman

The second thought that came to my mind is that I’ve never went for more than a few hours without food. In other words, I’ve never experienced “real” hunger.

So I decided to go on a 72 hour water fast i.e only water and no food for 3 days straight. My aim is to gain a first hand experience on hunger and to check if I have the mental fortitude to complete it.

Benefits of Fasting

The scientific benefits of a 72 hour fast are

Ketosis – It’s a state where your body starts to burn fat ( makes ketones) for energy. This happens because you no longer have enough carbohydrate intake to fuel your daily activities. You can also achieve this by following the Keto Diet. Typically starts between the 24 – 48 hour mark.

Autophagy – Literal translation is Self Eating. Despite the horror inducing name, it’s actually good for you. Your body recycles old, damaged cells to make new ones. Studies estimate that this happens around Day 3 of fasting.

May promote better Health and Longevity – Several studies point out that fasting may improve your blood sugar control, lower blood pressure and reduce inflammation.

Note: I didn’t monitor my body weight,blood sugar or ketone levels during this exercise. My primary reason for doing this was to test my will power more than anything else.

The Plan

The plan was to stop eating after breakfast on a Thursday morning and continue fasting till Sunday morning. So, I had two work days and a weekend to work with. I allowed myself to have only water or green tea/black coffee (no milk or sugar) as they contain near zero calories.

First 24 Hours

The first day was too easy. It was a busy day at work, so I haven’t thought about food at all. Around afternoon, I started to feel active and sharp. There was a little rumbling in the stomach by evening, but it was manageable.

24 to 48 Hours

Everything was normal for the first half of the day, still felt very active. Work again kept me busy most of the day but felt a bit hungry and weak by the evening of Day 2. I noticed that my sense of smell towards food has increased. 

At night, I had a disturbed sleep. Managed to get just 6 hours of sleep in total.

The Last 24 Hours

Day 3 was tough. I woke up with a headache, felt hungry and tired. Also felt dizzy whenever I made a sudden movement. Being a holiday made it much easier though, as I just rested at home. Had a cup of green tea for breakfast and one black coffee in the evening.

My sense of smell further increased. It’s like a lame superpower. I could now, staying in living room, identify which dish was served at the dining table, just by the aroma.

Around 8 pm, I felt relieved that finally, the fast was coming to an end. All I had to do was sleep through and I can break my fast the next morning.

I was wrong, I couldn’t sleep at all. Struggled hard to sleep till 12 am and then woke up by 1-30 am. Again slept at 3 am only to wake up by 5 am. Then, I realized that I forgot to take sodium (salt) during the fast. So had some water mixed with a pinch of salt.

Then, laying on bed, wide awake, with headache, hunger and fatigue, I waited for the next two hours to pass. Felt like forever.

Breaking the Fast

Finally, Day 4 has arrived and I have successfully completed the task. I broke my fast with some hot lemon water. It helps activate your digestive system after such a long gap. Half an hour later, I had a very light breakfast. Do not have a big meal after long fasting, It’ll upset your digestive system.

For the rest of the day, I slept for a few hours, ate a small meal and slept again. By evening of Day 4, I finally felt like my former self.

This has definitely been a challenging experience for me and I learned the following lessons from this experiment.

New Perspective on Food and Hunger

I realized that the feeling you have when you miss a meal is not actual hunger. It’s just your brain pushing you towards “craving” something its used to. I also concluded that much of my food intake is to satisfy my cravings rather than actual hunger.

Its ok to miss a meal, you don’t HAVE to eat 3-4 times a day.

It’s more Mental than Physical

Fasting for longer periods demands that you stay disciplined. It’s got more to do with your mental strength. I did experience the physical effects i.e headaches, hunger, fatigue on day 3. But on a scale of 1 to 10, 10 being debilitating discomfort/pain. I would rate the physical suffering to a 6 at max.

However, I was tempted to quit several times not because of the physical discomforts, but mental ones. On day 3, my brain started festering me questions like

Why the hell are you doing this?

Everyone else is enjoying their holiday, Why can’t you?

Food is just one click away, fasting for 48 hours is good enough, Why don’t you treat yourself?

Is this worth losing your sleep over?

My answer to all these questions : “Shut up, Brain!!! I’m in charge here”

It’s also easier to resist hunger when you’re busy. Free time is when your brain starts playing tricks on you.

The Body Adapts

Your body depends on your glycogen stores for energy. Once these are depleted, it moves to ketones, built from fat cells. It also has the ability to consume protein from your muscles to survive. During times of starvation, the body can slow down its energy requirements to survive longer.

Basically, your body has ways to sustain and adapt without food for long periods of time. Many people regularly do a 5 – 7 day water fast while continuing their normal routines.

High water intake is mandatory though.

Summary

If you’re thinking about doing this, I would recommend you start with a 24 hour fast and work your way up to 72 hours or more, over time. If you have any existing medical conditions. DO NOT TRY THIS without consulting your physician first.

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