My First 5 Day Fast

July 10, 2020 · 10 minute read

My experience with fasting

In my faith as a member of The Church of Jesus Christ of Latter-Day Saints we fast once a month. This is a 24 hour fast of no water and no food, commonly known as a black fast or a Jewish fast. I have been doing this monthly fast since I was about 8 years old. We then donate the money we saved on food and contribute to a fund to help the poor and needy. See Gospel Topics - Fast, Fasting.

A couple of years ago I started experimenting with intermittent fasting and extended fasting. My intermittent fasting routine now is either eat one meal a day (OMAD) or eat my first meal around 2-3 and dinner around 6. I will usually do OMAD for 2 or 3 days a week. Sometimes I cheat and eat Sunday breakfast, but that is my usual routine.

Once a month I usually do a longer 2-3 day fast. Because once a month my faith does a one day fast as a group, I don't really feel it much of a sacrifice to do a 24 hour fast anymore so I do at least 2 days. I'm not trying to compete with those around me, I just don't feel it much of a sacrifice. I might have already done 3 or 4 OMAD days earlier that week.

The purpose of the extended fast

I am already pretty lean so my purpose in fasting is not to lose weight.

There are many benefits to extended fasting such as increased mental clarity, autophagy, cancer prevention, and more. See Dr. Fung's amazing work The Complete Guide to Fasting. You can also find him on YouTube.

Fasting is an ancient practice. You can read about extended fasts in the bible. We have accounts of Jesus, Moses, and Elijah fasting for 40 days.

And he [Moses] was there with the Lord forty days and forty nights; he did neither eat bread, nor drink water. And he wrote upon the tables the words of the covenant, the ten commandments.

KJV Bible, Exodus 34:28

And he [Elijah] arose, and did eat and drink, and went in the strength of that meat forty days and forty nights unto Horeb the mount of God.

KJV Bible, 1 Kings 19:8

Then Jesus was led by the Spirit into the wilderness ... After fasting forty days and forty nights, He was hungry.

KJV Bible, Mathew 4:2

In Judaism the number 40 has some significance, so they probably didn't actually fast for a full 40 days. But I'm sure it was longer than 1 day. The number 40 occurs a lot in the Bible.

See scripture search "forty days", Wikipedia 40 Number - Judaism, and also Ask the Rabbi - The Number 40.


I had been thinking about trying a 5 day fast, so last few weeks I have not been doing my daily fasts like I usually do. I also tried to up some of my portions. I've tried in the past to do 5 days but I get to the 3 day mark and feel like I need to end the fast.

The only thing I had on this fast other than tap water was sea salt and a bit of lemon juice. See my version of ketorade recipe.

Day 1 - Sunday July 5, 2020

Like I said earlier I am very comfortable doing one meal a day. I have built up to doing OMAD for the last few years.

Day 1 felt about like a normal day, although I don't usually go to bed hungry.

Day 2 - Monday July 6, 2020

Surprisingly, day 2 was the hardest day of the fast. I felt tired and my brain was pretty foggy. It was a bit hard to concentrate at work.

Another thing I noticed was that occasionally my heart would race. My pulse would increase to around 90 bpm. This is actually pretty common for me for a day 2 or 3 fast. My problem might be dehydration which I talk more about in days 3 and 4 of this post.

I did take some pink Himalayan salt and a bit of lemon juice mixed with water. That seemed to help a bit.

By the end of the day I was feeling a lot better and not sluggish and foggy. I went to bed at my normal time around midnight.

Day 3 - Tuesday July 7, 2020

I woke up a bit earlier than usual feeling very refreshed around 6:30 a.m. I went for an hour morning walk. I usually go on a half hour walk every morning. I was feeling great so I went a bit longer than usual.

At this point in the fast I started feeling really great. I had a lot of mental clarity and was really productive throughout the day.

I wasn't even that hungry anymore. I did occasionally have the desire to eat because I saw what the rest of my family was eating, but I didn't really feel hungry.

It made me think of my relationship with food. Sometimes I eat because I want to eat as entertainment or eat to be social, which is different than the body saying I need to eat. I feel like I didn't learn what true hunger was until I had done several 3 day fasts.

I felt especially more light headed than day 2. From what I've read is that the body sheds salt as it burns through your glycogen stores. At this point I was probably well into full ketosis.

On breaks from work (I work at home due to COVID 19 quarantine) I would go outside and weed my garden. When I would stand up I got really light headed. I figured eventually my body would adjust so I pushed through.

I had a lot of energy and stayed up a bit later than usual and went to bed around 12:45 a.m.

Day 4 - Wednesday July 8, 2020

I woke up again a bit before my 7 o'clock alarm and felt pretty good. I notice that I sleep really well on a fast and that I need less sleep than usual.

I felt a bit dehydrated although my pee was pretty clear. I drank a big glass of ketorade (lemon juice, lime juice, pink Himalayan salt) and then went for an hour walk.

I was not really that hungry although I felt like I was moving a bit slow.

I did get a metallic taste on the roof of my mouth on and off throughout the day.

The first couple of times I did a fast longer than 2 days I would get a strong metal mouth taste, especially in the mornings. I have done this enough times now that I rarely get metal mouth anymore.

I was again experiencing a lot of light headedness so I did some reading online and most people suggested take in more salt to retain more water. I think I was a bit dehydrated and my blood pressure was low. So I mixed up 1 teaspoon of sea salt in about 2 cups of water and drank that.

T.M.I. alert! Be careful not to overdo the salt because it will flush out your bowels. I didn't know salt water had this effect. The salt water flush (SFW) is part of The Master Cleanse.

Anyway I confirmed that my bowels were indeed empty.

I felt much better after the salt and I could sit and stand without feeling light headed.

I again went to bed late around 12:45 a.m.

Day 5 - Thursday July 9, 2020

Considering I went to bed late I did not expect to be done sleeping around 5:45 a.m. I felt fully refreshed and I didn't get drowsy throughout the day.

Again I had a large glass of ketorade.

I had some extra time in the morning so I went for a hike in the mountains before work. Where I live I have access to two canyons full of trails about a 5 min drive away.

I went on an hour and a half long hike. I had plenty of energy, although I was a bit winded more than usual going up the first hill of that hike.

I felt really great the rest of the day. I felt like I could have taken the fast a couple more days. I am already quite lean and I don't want to waste away so I am only going to day 5. I was surprised how good I felt.

Breaking the fast

For me one of the hardest parts of fasting is breaking the fast properly. Choosing not to eat is pretty simple. Not always easy but really simple. When you go back into eating food it's really tempting to just eat until you can't eat anymore.

For a 1 or 2 day fast I haven't had too many troubles just eating dinner like normal, but for anything longer than that I have had to be more careful. The digestive system shuts down and needs a bit of time to get going again.

If I do too much too fast I experience lots of intestinal distress like bloating and diarrhea and I often don't sleep very well that night.

So it is a good idea to have a plan when breaking your fast. Plan out what you will eat, how much, and when.

First meal

I broke my fast with a small meal around 4:00 p.m.

Watermelon is like cheating coming off a fast. It is mostly water but you feel like you have eaten a lot. It is pretty low carb so it will not spike your insulin (as much). I haven't tried it but you could probably gorge yourself on watermelon without any adverse effects.

A note about fermented foods. I have found coming off the fast I do especially well when I can eat something fermented. When you fast and the digestive system shuts down and I surmise that a lot of the gut flora also decreases. When you eat fermented foods at the break of the fast you replenish the gut with new bacteria.

I love fermenting vegetables. I have fermented jalapeños, carrots, onions, garlic, Brussels sprouts, cabbage (Saurekraut) and of course cucumbers. They are all yummy. My kids also like most of it too.

Second meal

The 4 o'clock meal settled really well so I had a somewhat normal portioned dinner around 7 o'clock. We had a picnic at the park. I tried to keep the carbs really low so I skipped the bread or any tortilla chips. We had fresh made chicken salad sandwiches. My wife even made fresh rolls (she is a master bread maker). So I had the sandwich without the bread 😞.

This meal might not have been strictly keto, but it was pretty close (I probably had a total of 8 raisins in the chicken salad). I slept really well that night and I felt great the next morning.

Eating a keto-like diet coming off the fast keeps your insulin low and eases your body back out of the fast. My rule is to avoid breads, chips, cookies and the like. I choose instead a small portion of meat, cheese, any vegetable.

The day after breaking the fast

Beware not to overdo it the next day as well. I have experienced some gut problems the next day if I eat too much or a bunch of junk. I had a bunch of kettle corn the second day after a fast one year on July 24th (Pioneer Day in Utah) and my guts were not very happy.

I try to get back on my normal eating routine the day after I break the fast. I don't try to make up for the lost weight immediately.