When Zero Food is Healthy
Are We Eating Ourselves to Death?
Welcome to Polymathic Being, a place to explore counterintuitive insights across multiple domains. These essays take common topics and explore them from different perspectives and disciplines and, in doing so, come up with unique insights and solutions. Fundamentally, a Polymath is a type of thinker who spans diverse specialties and weaves together insights that the domain experts often don’t see.
Today's topic addresses accepted tropes of eating, diet, and insights into how little we really know about something as simple as eating / or not eating. I’ll share some of my experience on this topic culminating with my most recent 10-day fast. Yes, that’s 10 days of nothing but water, coffee, and electrolytes. I’ll share things I’ve learned along the way about the benefits, and lessons learned about what not to do.
How Wrong are we About Eating?
Make sure you eat three square meals a day and be careful not to skip a meal. Pretty much sums up the guidance I had as a kid. That, and growing up where low-fat diets were the generally accepted status quo supported by that ubiquitous food pyramid that had us eating tons of carbohydrates.
And yet our health is rubbish. Obesity is endemic, diabetes is on the rise, cancers are everywhere, and our mental health is in shambles. But what if we’ve been fed very unscientific, and often politicized inaccurate information?
While I hope these following examples aren’t new to you, I wanted to highlight them as ones I found the most transformative in how I think about what I eat, how I eat, and even if I eat.
We like to think our modern medicine and research understand our bodies but we really don’t know how our entire body works together to process even something as ‘simple’ as food. We just don’t. When you dive into the literature and studies, everything is fractured, siloed, and atomistically, not holistically studied. So we know a little about proteins, fats, and carbs, and we have correlated links to simple effects, but our bodies are incredibly interconnected, complex, and multivariate. Understanding our body is fundamentally one of the more challenging polymathic enterprises and we are just scratching the surface of what we think we know and have difficulty actually explaining the mechanisms even with our modern science! We really have to sit back and turn off our hubris and engage our food with curiosity and a systems perspective.
The food pyramid most of us know was created by the Department of Agriculture, not the Department of Health. It seems that the grain farmers won out over the dairy farmers in this one. About the only thing they go right was limiting pure sugar but those simple carbs at the bottom aren’t much better. Following the pyramid is merely following the money of the lobbyists, not the scientists who won government approval.
Our bodies don’t need three meals a day. Intermittent fasting, basically skipping one meal a day, typically breakfast is fine. In fact, over the past 10 years, more and more research has come out showing the major benefits of intermittent fasting for healthy living. The meals you do eat still need to be healthier with a better balance of lower carbs and less processed food (and yes, my bane is crispy Cheetos!)
Fat is good for us. Like essentially good for us. As in low-fat diets paradoxically are correlated to obesity, Alzheimer's, and more! Your brain needs fat and cholesterol to build, support, and maintain neurons. Furthermore, fat is satiating whereas carbs are not. Try sitting down and eating an entire steak with the fat and see how you feel. Next time add all the potatoes, rice, and other carbs and see if you feel fuller or not. Typically with the carbs, you’ll feel hungry in about 2 hrs because carbs spike our insulin and make us hungry again whereas fat satiates much longer due to avoiding the sugar crash.
Our gut health IS our brain health. Our food is so processed and sanitized that our gut biomes are totally out of whack. When our gut is distressed by this imbalance, it releases stress hormones that our brain picks up and doesn’t know how to differentiate from external threats, it just knows it’s in trouble. (The proverbial, “I’ve got a gut feeling,” is real) We evolved while eating bacteria-coated foods as well as using fermentation as one of our earliest food preservation techniques. We need good bacteria in our guts and our food today is super sanitized. As anecdotal evidence, a friend of mine, suffering acute anxiety, was prescribed probiotics due to poor gut health and saw a nearly immediate reduction of anxiety.
Our bodies need stress. Just like our immune and muscle systems, our gut needs stress to help reset, recover, and relax. Our body is created to be Antifragile, which is a system that gets stronger under stress. Ironically, we are weakest and most fragile when we avoid stress on our bodies. This is where fasting comes into play as our bodies actually react to fasting in much the same way that our immune system reacts to pathogens. That is, it goes to work fixing, cleaning, and rebuilding our body in response to stress.
If these are contrary to what you’ve been told in the world of food, then these are definitely things that you should dig into more and understand better because if we aren’t getting these 6 things right, being healthy will be much harder. (If there is a topic here you’d like me to dig into more in the future, please leave a comment!
A Bit More on Fat:
Fat is one of the things in the past 30 years that we not only got wrong but got dead wrong. So wrong in fact that it may be affecting our brain health. Recently there’s been a lot more discussion on this topic, but suffice it to say that our current understanding of diet is incredibly siloed and myopic across our bodily health. How so? Well, fundamentally heart health and brain health are not studied together. So a diet that is low in fat is supposed to be ‘heart healthy’ even though it also leads to a dramatic rise in dementia. (with a nominal positive impact on heart health)
This is probably the most counter-intuitive of diet trends. I don’t intend to do a full expose on the topic here, but suffice it to say that people like Max Lugavere are doing great work exposing this aspect of dietary consequences of low fat as the informative podcast below details his exploration into his mother’s diet and dementia. His book Genius Life also details these connections (of note, Max is not a scientist, but a journalist and was able to look across the research silos) Bottom-line here, we need to do critical systems research into the role of fat in our health and completely rethink the last 50 years of advice.
Intro to my Diets Over Time
I’ve never been one to go for fad diets. For about 15 years I loosely followed an outline of protein-heavy, fat-reduced, and carb balanced as was recommended for weight lifting. I was never super strict and didn’t do any A/B testing to validate. It was just a guide for me. My wife and I have done a few sugar purges over the years (typically in January) and in doing so, dramatically reduced the volume of processed sugar in our lives which probably had the best net benefit for my health to date.
I did a FODMAP-restricted diet for 2 months in 2017 on the recommendation of my gastrointestinal (GI) doctor as we were trying to tease out my Irritable Bowl Syndrome (IBS) symptoms. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, which are short-chain carbohydrates (sugars) that the small intestine absorbs poorly. FODMAPs are in lactose, wheat, legumes, many of our favorite fruits, a lot of vegetables, and in common spices like onions and garlic. It’s actually a very difficult diet to pull off because it’s really hard to control for all the variables.
A unique diet I tried was the Carnivore diet in 2020, 2021, and again this year. I started this diet as both an elimination diet to try to trace down my IBS as well as planning a bit of weight loss. Unlike FODMAP, the carnivore diet was incredibly easy and saw great fat loss as well as not feeling like I had to calorie restrict. I was eating until I was full and actually struggling to eat more than 1000 calories a day! I just wasn’t hungry. This diet is similar to Keto but without carb counting, because you just don’t eat carbs. It’s just animal proteins like Beef, Chicken, Eggs, Cheese, etc. I saw solid, and easy weight loss although I never did figure out those IBS triggers.
Intro to Fasting
Over the years I’ve done some cursory research into fasting. The concept is so counterintuitive as to be fascinating. Not eating food can make us substantially healthier!? This gets into point 6 above. Our bodies need a certain stress/shock/break for health. While there are hundreds of sites, videos, and podcasts, two I really like are Fasting: Awakening the Rejuvenation from Within by Valter Longo:
And Tim Ferriss and Dom D’Agostino on fasting and cancer:
With those two in mind, I’ll flesh out some of the details of the benefits of my fasting experiences below so as to not reiterate too much.
My First Fasts
I did my first 72 hr (3-day) fast in 2018 on a whim based on some things I had read and listened to on podcasts; I knew nothing. On day 2 I crashed hard, and on Day 3 I was struggling just to get to dinner. I counted it as a win for my first go-around. I didn’t learn a lot other than, yes, I could do it. But it wasn’t much fun. My second fast was in 2021 with a friend of mine. We planned to start with a 72hr fast and then transition into Carnivore. This went as well as my first fast for both of us and again, left me frustrated.
So what happened that made it so hard? It was brutal because the entire three days is the body’s transition into Ketosis where your digestive system transitions from burning easy, available, cheap carbs as glucose, into transitioning to burning ketones which is a method where the body takes fat and converts it into usable energy. This transition process is not a lot of fun for most people although it does get easier the more your body gets used to transitioning.
So the second fast was again a win for getting it done, but like the first one, I made it harder than it needed to be and I don’t think I got all the physical benefits I had hoped for. I certainly didn’t get the mental benefits everyone talks about!
Learning from the Past
This third time my goal was a 96hr (4-day) fast and to jump-start the ketosis transition I started with 2 weeks of carnivore first. This allowed me to get into ketosis and stabilize my digestive system around burning fat. Unlike the first two times of fasting, after 48hrs, the only thing I needed was to increase my electrolyte ingestion as the body purges a lot more out than normal. This time I didn’t crash, I didn’t fade, and I felt fantastic!
Closing in on day 4 I talked to a couple of friends who recommended going longer than 4, and up to a 10-day fast to maximize the benefits. The reason for capping at 10 days is this is about as far as you can go without some more significant re-feeding protocols while at the same time maximizing the benefits from the long-term restrictions. I felt great at this point and so I decided to continue.
One thing I wanted to avoid was muscle loss which can happen if your body fat percentage gets too low. To make sure, I took my body fat measurements with calipers. I came in at a respectable 12.5% body fat which puts me at the lean end of ‘Athlete.’ What surprised me was just how much I could still lose without worrying about muscle loss. A pound of body fat contains 3500 calories, and my Basal Metabolic Rate with exercising three times a week has me burning about 3100 calories a day. This meant that I’d only burn about 0.85 lbs of fat per day MAX while on the fast. Even if I went 14 total days, I’d only reach 10% body fat so I had plenty of margin. With my muscle loss worries mitigated and the potential for major health benefits, I figured, well why not go longer? And so I continued.
So what are the benefits, beyond weight loss, of a longer fast? The most important one I learned about is Autophagy. This is a nifty feature in which your body breaks down and reuses old, unhealthy cell parts so your healthy cells can operate more efficiently. It’s effectively a form of pruning/house cleaning to trim out the bad cells so you can replace them with healthy, new cells. Furthermore, when coming out of a longer fast, the body ramps up stem cell and white blood cell production to help repair and rebuild after the autophagy purge. This has shown dramatic improvements in gastrointestinal health, cancer mitigation, and even brain repair and growth benefits.
As typically happens, my motivation from all this great insight ran face-first into Day 5 which was one of the toughest days. But that’s probably because I thought it would be a good idea to cut out caffeine... It was a terrible idea! I corrected course with a mid-afternoon cup o’ joe, I was feeling great again. As I looked into whether I should try to cut it out, I found indications that coffee actually helps with autophagy while on a fast. So I didn’t have to do much more self-convincing to keep coffee in hand. This initially bothered me as I dislike the feeling of addiction, and I’ve often gone cold turkey on caffeine with no ill effect. However, while on a fast, with the tighter tolerances your body is running at, changes like this are exacerbated beyond normal.
Day 7 was also a little rough toward the end. I chalk this up to a morning workout plus working outside building mountain biking trails by hand in the Tucson sun. Yes, I think I see the correlation. Days 8-10 were honestly boringly easy. Looking back, what made the fast hard wasn’t the lack of food, but self-inflicted extras because I was feeling really good.
My refeeding on day 10 was pretty simple. I drank bone broth with salt, had some buttered cod with capers for dinner, and avoided dairy for the first 24 hrs. I stayed on the carnivore diet for three more days until finally breaking back into my normal diet over the weekend. The only issue I had was a little heartburn/acid reflux at night for two nights as my stomach reacclimated to digesting food. Plus I did kind of jump right back in more than I probably should have. (there seems to be a non-moderation-trend going on with me here)
One major benefit I have realized, but will have to report back later on the longevity, are that my IBS symptoms have substantially reduced in the week+ since I broke my fast. This fast seems to have done, in 10 days, what I’ve been chasing for 10 years. Again, more to come on that to see how long it lasts.
Things I learned this time
Fundamentally, I think the most shocking thing was that the human body can go 10 days with zero food and be fine. Not only fine but feeling good!
It takes a LONG TIME to burn fat weight. Even at my higher metabolic rate, I’d burn less than 0.85 lbs per day. I could have gone an entire month and still been above 5% body fat and I was starting at 12.5% which is pretty lithe, to begin with. The average American male carries 25% EXCESS (total 30-45%) body fat translating to ~55lbs of fat which, even at a robust 2600 daily calorie burn (0.75lbs of fat), it would take 73 days to burn off even if you are eating nothing. And that only gets you down to 15% body fat.
I wasn’t hungry. I could stand in front of food, food I loved, and I wasn’t hungry. Don’t get me wrong, I missed food but my mouth wasn’t watering and I could walk away and not feel like I was restricting anything.
From day 5 - 10 I felt like I was in a pretty solid ‘zen’ state. My brain was clicking, and I was still working/writing, but I felt calmer. My wife noticed I wasn’t as chatty and wouldn’t just randomly strike up in-depth philosophical observations like normal. But it was a very calm feeling in my brain which I actually kind of enjoyed as a rare situation.
I regret not getting a Ketone meter when I started. It would have been nice to have measured it from Carnivore through the fast. I ended up getting the KetoSens Blood Ketone Monitoring Starter Kit and it seems to work great! My Ketones were in the 6mmol range on day 7 which isn’t surprising.
My mouth tasted terrible! Like, brushing my teeth three times a day terrible. I didn’t have bad breath but it didn’t taste good at all. A stick of gum helped a lot. This is a side effect of ketosis and a bit of autophagy and my body was shedding cells, toxins, etc.
You need a LOT of electrolytes. I was adding salt, but I needed more potassium (upwards of 1600mg per day!) I picked up some flavored packets I think are very good but I’m not a big fan of fake sugar so next time I might go unsweetened.
Don’t try to cut out caffeine in the middle, or at least try to wean yourself a bit. I can normally drop coffee for a few days cold turkey but this kind of threw me off.
My blood pressure dropped around day 5. I had to really be careful when standing up so that I didn’t get too lightheaded. I ended up getting a blood pressure cuff out of pure curiosity, and because I think I’ll find it useful for other things in the future like meditation, freediving, etc. My blood pressure wasn’t as low as I expected but got down to 120/75 which is where I was at in the Army.
I was really surprised where I hold my fat. It’s largely in my chest, shoulders, and arms. Which is great because it really fills out my structure. When I lose the fat, I actually start to look quite skinny. My belly fat is the hardest to remove. I feel like it shreds off the places I don’t want (chest, shoulders, arms), and holds on for dear life where I’d like to look leaner (abs).
The hardest part was the boredom. I didn’t sit with the family during mealtime, mostly because I had nothing better to do than correct my kids’ table manners and that didn’t make me much fun. But not having the breaks for food or some of that family time was honestly more boring than expected.
So What’s Next?
I’m glad I did it and I feel like I met a challenge. Next time I think I’ll focus on 7 days because it’s the sweet spot of maximal benefits with the lowest consequences. I will certainly apply my lessons learned like getting into Ketosis before starting the fast that’s for certain. I plan to do more body measurements and tests along the way just out of curiosity. In general, I think I’ll be doing a 7-day fast about once a year going forward. I’ll probably pair it with my annual Dry January and sugar purge as I believe the benefits are as essential as a regular diet and exercise for my overall health. Maybe next time I can convince my wife to join me :)
The best part is just how much I learned that is counterintuitive to everything we have been taught about eating over the past 50 years. Truly, not eating for 10 days might be the healthiest thing you can do all year! I’ve certainly seen the mental and physical benefits of this experience.
What are your fasting experiences? Please feel free to comment and provide your lessons learned and insights. Also, as I work to grow these essays, please share and subscribe if you already haven’t!