Extended Fasting: Why I Ate Nothing for 3 Days & How It Felt

Photo by Michael Oeser

Experiment: Do a 3-Day Water Fast (consume nothing but water, black coffee, and unsweetened tea)

Disclaimer: I’m still not a doctor. While I do recommend trying some of my experiments like this if they make sense for you, none of this should be taken as medical advice. Any action you take based on the information presented here is at your own risk…

Ok, so why…

• Like most humans, I ate/drank more and different things than I usually do over the holidays. Fasting is a great way to clean house in your digestive system and reset your eating habits.
• This also meets my two requirements for an experiment: 1) I believe it can make me a better person… or at the very least teach me something worthwhile and 2) it’s challenging enough to scare me a little.
• I came across far more benefits than anticipated in my research. Here are 10 of the most compelling short-term benefits, which are often the sexy hooks that get us into fasting:
  1. It’s a Time and Money Saver
  2. It’s Simple to Try
  3. Productivity Gains (yes, please!)… for bonus gains, try this technique
  4. Reduce Your Addiction to Food
     • Hunger is more a psychological response than anything else. The hormone that activates your hunger gremlin is appropriately called ghrelin.
     • It comes and goes cyclically with our daily eating routines, much like melatonin comes and goes with our daily sleep routines.
     • Fasting throws a wrench in ghrelin’s cogs, much like exposing a gremlin to sunlight. Do this enough and it stops. No more addiction to food. You’ll still enjoy eating, just on your own terms. Without all the ghrelin gremlin chatter.
  5. Get Well Sooner
     • When we are sick, we do not typically feel as hungry. This is our body’s triage plea: give me a break so I can tend to what matters most right now.
  6. Dump the Extra Junk Out Yo’ Trunk
     • Our digestive systems have been working hard our entire lives. They can use a break and take the chance to clean out the extra crap that has accumulated over the years.
     • Sages like Aristotle, Socrates, and Hippocrates practiced fasting for its professed purification and healing abilities.
  7. Upgrade Yourself
     • After 16 hours of fasting, autophagy begins. Translating to “eating yourself” in Latin, your body is finding and consuming broken and old cells. This is good.
     • When those junky cells are left to accumulate, they can lead to degenerative diseases like cancer or Alzheimer’s over time. Eating them is thought to reduce incidence of these diseases. Your body grows new cells to replace the old ones, giving you an upgrade from the inside out.
  8. Easier Travel
     • Once you beat hunger addiction, you won’t get hangry and throw a toddler-like tantrum if the planes, trains, and automobiles don’t have Biscoff cookies for you.
     • You also don’t have to plan your trip rigidly around mealtimes.
  9. Fall in Love with Food Again
     • For many people who do prolonged fasts, the first taste of food again is incredible. I’m looking forward to that moment!
  10. Spread the Movement
      • Since most businesses stand to benefit from increased—not reduced—consumption, don’t expect to see them advertising fasting. It’s our job to spread the word about it, and the best way to do this is through our actions.

• Now here are the true reasons you should practice fasting… the long-term bennies:
  • Boost your metabolism (& shed excess weight)
  • Cancer prevention and chemotherapy effectiveness
  • Prevent onset of type 2 diabetes (or reverse it for those who have it)
  • Better blood sugar control
  • Relieves inflammation
  • Gain greater awareness of your eating habits and appreciation for food
  • Can clear up your skin (as long as you stay hydrated – you better drink that water)
  • Helps you live longer

Uh oh…

• The most I have gone without eating is 24 hours, so I’m just trying to do that again… 3 times, consecutively, with no breaks. No big deal.
• Some people who have done extended fasts report being so wired at times that they find it hard to sleep. Yikes. This is likely due to the body switching into ketosis—fat-burning mode—but may be a bit unsettling nonetheless.
• No free samples at Trader Joe’s… I kid. That is definitely not happening right now. Remember those days though.

About that…

• Won’t I starve? You won’t starve. We all have reserves of fat, 34 pounds for the average human. Since each pound represents 3,500 calories, or nearly 2 days of food, we have plenty of built-in “snacks” for our body to consume for a while without eating.
• In fact, the world record for the longest fast ever is 382 days!
• According to Dr. Fung, author of The Complete Guide to Fasting, “Fasting is running for health. Starving if running because a lion’s chasing you.”

I betcha…

• Based on what I read, I am expecting Day 2 to be the hardest. Most people say it gets much easier after that point, roughly when your body switches from burning glucose to fat, which we have far more of readily available.
• I am expecting to have some periods of low energy as well as periods of high energy and productivity.

The Last Supper (Pre-Fast Meal):

• For my last meal at 5:30pm on a Thurs evening, I enjoyed a large but light arugula salad with olive oil, red wine vinegar, some pistachios, and half an avocado. Note it was intentionally very low carb to help my body reach ketosis—and thus make me feel much better—sooner in the fast.
  • You feel better because your mind and body don’t have to work to find glucose to burn for energy and instead use available ketones, an alternative source of fuel that the liver produces from your body’s fat.

First 24 hours (Thurs eve – Fri eve):

• Day 1 was not too tough, though this was never the part that concerned me.
• I slept great Thursday night, as expected, given I was only a few hours into the fast at that point – nothing for my body to have even registered yet.
• On Friday morning, I had unsweetened coffee… not my fave, but better than I remembered it being from my month of No Sweetener. I sprinkled in some cinnamon and sea salt for a little flavor enhancement.

• I also took 2 salt pills—I like Salt Stick brand—and ½ tsp Trace Minerals drops, recommended by a friend to maintain electrolyte balance during the fast. In the evening, I took 2 more Salt Stick pills to maintain electrolytes and retain water better.
  • Quick note: While it’d be awesome to get paid for my brand recommendations, I have no current affiliations with any of them. They have just worked for me.
• I did a rigorous strength training workout and didn’t feel I was lacking any energy to do so. Counterintuitively, I often feel more energy to work out after a shorter-term fast, which this has been so far. I don’t plan to do strenuous activity during hours 24-72.
• Hunger came in a few times during this 1^st 24 hours as if it was a little phone notification, reminding me “Hey, we usually eat now. Do you wanna do that?” But just like a phone notification, it was easily dismissible.

• I accomplished more at work without spending any time cooking, eating meals, or having any snack breaks.

Hours 24-48 (Fri eve – Sat eve):

• Brrrrr… I normally run cold during the day and heat up at night. However, my body temperature is running lower at all times now, as I find myself bundling up more during the day and actually using a blanket at night. And I’m usually a just-undies-and-a-single-sheet kind of sleeper, even in the winter.
• I slept wonderfully again. Hoping the trend continues during the final night.
• Woke up very thirsty Saturday morning. Will repeat my electrolyte protocol and aim to get in a little more water today.
• My typical morning routine includes a 2-minute HRV (Heartrate Variability) reading using the free Elite HRV app. This morning my HRV was very low, indicating elevated sympathetic activity in my body.
  • This is expected since it is the body’s involuntary response to dangerous or stressful situations, i.e., when it thinks you cannot find food.
  • A flood of hormones kicks in to boost your alertness. For this reason, I’m feeling greater mental clarity than usual.
  • At the same time, it’s a good indication I should take it easy, as planned, and not do any substantial exercising today.
• My nose feels clearer and more powerful.
  • My sense of smell is heightened, maybe more than necessary. I can smell our dog’s breath better, as well as my own. (Shame!) Less than ideal breath is a side effect of extended fasting.
  • It is refreshing to wake up and be able to take deep, clear breaths 1^st thing in the morning though. Stuffiness be gone.

In general, I feel a heightened awareness… of my body, mind, and surroundings. There is something very primal about the feeling.

• Occasionally, I feel slightly lightheaded but nothing concerning.
• I felt a little meh in late morning and went on a long, sunny walk outside—another tip from a friend. This made me feel wonderful and gave me a chance to catch on the phone with my family—a great way to spend some of the extra time you have.
• Around midday when I typically feel that circadian rhythm slump—on top of lagging a bit while digesting lunch—I felt supercharged today.
  • I didn’t even need the 15-20min siesta power nap I take religiously after lunch.
• I’m drinking lots of water and loving naturally flavored sparkling water (zero calories) as a means to mix it up. Squeezing in a little lemon or lime juice is fair game too and is helping jazz up my agua.

Hours 48-72 hours (Sat eve – Sun eve):

•  Phew… Slept great again. This was a big relief because this was the night some bloggers had expressed trouble sleeping due to their elevated heart rate and racing mind.
  • I fortunately did not have these issues.
  • When I did my morning HRV check, my heartrate was 30% higher than usual. Not an issue though, as I otherwise didn’t notice it.
  • Went for a hike with my husband Will, cousin Jessie, and our dogs. It was a bit hillier than expected, so I felt a little hungry afterward. Some tea helped handle that though.
    • This was the first time I enjoyed green tea without any almond milk or sweetener.
    • Also, Will was a great partner and joined me for the final day of the fast—especially nice since I didn’t have to see or smell his tasty food.
• It really does get easier after you’ve hit a certain point in the fast—which I clearly have based on my energy levels and heart rate—when your body kicks into fat-burning ketosis.
  • You would think hunger would grow linearly or even exponentially as the fast progresses. In contrast, the strength of the little hunger waves that come and go has diminished.
  • In the same vein, while there can still be challenging moments, the practice of fasting gets easier once you get some initial experience. When you disrupt your hormonally driven hunger patterns, your body adjusts, and the hangry pangs lessen. Once you’ve tried and succeeded, you gain the mental confidence that you can do it again whenever you want to.
• Woo hoo – I made it! Admittedly, I have been counting down the hours, mostly because I started to miss the enjoyment of eating food. I was so focused on what I was working on at the time though that I blew past 72 hours before realizing it!

Before & After…

The Aftermath: beyond 72 hours:

• Surprisingly, I wasn’t super hungry at the end… certainly not starving. I could have easily gone another day if I wanted to.
• In no rush, 24 minutes after I hit 72 hours, I started slow and savored some delicious Trader Joe’s grass-fed organic beef broth. Just 100 calories but full of flavor and very satisfying.
  • I would recommend starting with this or, for vegetarians, miso soup.
• Two hours later, I consumed a spinach salad with olive oil and red wine vinegar, cucumbers, roasted pecans, some avocado, and nutritional yeast, followed by a square of dark chocolate.
  • I truly appreciated the food and process of eating more than usual. The flavors were a little bolder and brighter, or in the case of the chocolate, more complex.
• The rule of thumb for refeeding after a longer fast (24 hours+) is to ease back into your normal eating patterns over a period equal to ½ your fast, i.e., a 1.5-day recovery period for my 3-day fast.
  • This means starting by eating about ½ as much as you’d normally eat in a meal and then building back up to your normal intake over the course of this period.
  • There are also a few things to avoid in order to be gentle to your digestive system, which is being kickstarted back up:
    • Cruciferous veggies (e.g., broccoli, Brussels sprouts, cabbage, cauliflower, kale)
    • Lots of carbs (especially processed ones)
    • Lots of meat (some is fine – just don’t go crazy with it right away)
    • Beans
    • Alcohol
    • Dairy
  • Some recommended foods: some chicken or fish, spinach, cucumbers, bell peppers, walnuts, macadamia nuts, some sweet potatoes or squash, blueberries, dark chocolate.
  • It is a quite an interesting sensation to literally feel your digestive system booting up again. I followed these tips and had a smooth recovery.
• The body and mind reset from the fast have lingered for days after I started eating again. My mind feels clearer and sharper and my energy level consistently better than it had been pre-fast.
• While it wasn’t the main driver for me, I did lose 4.2 pounds, from 140.6 to 136.4. Typically, most of this returns as water weight, as you start refeeding and the sodium in food helps you retain more water. Not to mention, many foods like fruits and veggies contain water in them.
  • On average, the amount lost that stays off is 0.5 pound/day.

Where I Failed…

• I had some Teeccino (caffeine-free coffee-flavored herbal tea) that I’d picked up during my No Coffee for 2 Months experiment. I wanted a little more after my morning coffee on Day 3 but didn’t want to go crazy on the caffeine—especially with my heart rate up a bit—so figured this would be a good solution. As I was finishing the glass, something in my subconscious urged me to confirm that there aren’t any calories in this. But to my disappointment, there are 15 calories in it. Fortunately, this was not enough to ruin my fast, but I’m just glad it wasn’t any higher and will keep this in mind for future fasts.

Where I Won…

• I ate very low carbs during the day leading up to my fast. I believe this, along with burning up remaining glycogen via my Day 1 strength workout and my Day 2 80-minute walk, helped me reach ketosis faster. This improved the way I felt from midday Day 2 forward.
• The mineral/electrolyte supplements I used seemed to work, as I avoided some of the physical challenges some others have had during a 3-day fast, likely because they were electrolyte deficient.

What Surprised Me…

• Not eating made black coffee taste better.
  • Based on my No Sweetener experiment, it became clear to me that black coffee was something I could endure but not really appreciate. I normally add a splash of almond milk and a mini dump truck of organic stevia.
  • Day 1 the black coffee was better than I anticipated. Day 2 it became moderately enjoyable. And Day 3, to reward myself I enjoyed a black coffee from Peets that tasted delicious, something I’d never enjoyed before without sweetener.
  • Perhaps it was because my taste buds were so excited for any flavor beyond water. Or maybe it was thanks to my heightened senses of smell, and thus, flavor.
• I expected the magnitude and frequency of discomfort to be much higher throughout the fast than they were. I didn’t have nearly as many bouts of low energy as expected. It helped that I read a bunch beforehand to avoid the mistakes others have made. I’m grateful to them all for sharing these!

Whoomp, there it is…

• Since it was relatively easy and I felt great nearly the entire time, I would absolutely repeat this.
  • I’m excited as it feels like I’ve unlocked another tool that can be incorporated into my long-term habits for increasing my immune function, productivity, and longevity.
  • I’m going to plan on doing this 1-2 more times this year and see where I want to go from there.
• I highly recommend a crawl-walk-run approach. Start with Intermittent Fasting first, and then try a 24-hour fast or two, before attempting a 3-day fast. Much like in motor development, or training with a 5K before jumping to a marathon, the mental and physical conditioning will make the 3-day fast far more enjoyable.
• I also recommend using LIFE Fasting, a free, easy-to-use app to track your fast for you.

Thanks for reading! Please leave me a comment with any feedback and/or what you think my next experiment should be.

Did you dig this experiment?

Re(Sources):

https://www.austinrileygray.com/blog/3-day-fast-results

https://ideapod.com/3-day-72-hour-water-fast/

https://www.whitneyerd.com/2020/01/i-did-a-3-day-water-fast-the-how-why-tips.html

https://superhumanacademy.com/podcast/3-day-fast/

https://www.theunconventionalroute.com/3-day-fast/

https://www.theunconventionalroute.com/prolonged-fasting-benefits/

https://www.theunconventionalroute.com/water-fasting-tips/

7 DAY WATER FAST – NO FOOD FOR A WEEK (Before & After)

https://www.ryanandalex.com/3-day-fast/

https://www.hoylesfitness.com/weight-loss-and-nutrition/i-did-a-3-day-fast-heres-a-detailed-account-of-what-happened/