I've been practicing intermittent fasting for years.
I believe that IF and eating the highest quality foods are the answer to lifelong health and wellness.
I eat when I want and if I want. I rarely feel "hungry" or "tired."
If I decide to have a cheat meal, it's easy to return to my regular life soon after.
In this guide, I'm going to share with you my personal experience with fasting. By the end, I hope you will take it upon yourself to implement a fasting schedule in your life.
Before we dive into why you should incorporate IF into your life, we need to set a few things straight.
As with most things in the public consciousness, there are many misconceptions about intermittent fasting.
First of all, practicing intermittent fasting does not (necessarily) mean eating fewer calories.
Calorie restriction is eating fewer calories, while intermittent fasting is when you eat your calories each day and is independent of how many calories you eat in aggregate.
It makes sense that most people confuse the two, but for our purposes, we need to delineate the difference so there is no confusion or scapegoats that will result in the points being overlooked.
Going extended periods of time without food, usually for 24 hours or longer, is known as traditional fasting.
And while you should fast this way sometimes because of the health benefits, intermittent fasting is something different entirely and what we will be focusing on today.
To intermittent fast means to space your meals out at various times, or put, to eat in intervals.
The intervals will vary depending on what IF style you use.
As an example, let's say you typically eat 2,000 calories a day over 4-6 meals.
Then Monday rolls around and you decide to try IF, so instead of eating your 2,000 daily calories over 4-6 meals, you opt to eat the same amount of calories over 1, 2, or 3 meals with gaps between each meal and within a defined "feeding window." (More on feeding windows below.)
Your calories stay the same, but when you eat those calories changes.
This is, in a nutshell, intermittent fasting.
Of course, most people hear intermittent fasting and assume it's about not eating. But that's not accurate. Intermittent fasting is meal timing.
This is why everyone should practice some form of IF; Since we all have to eat food, we might as well choose an eating style that promotes our health and wellbeing over one that detracts from it.
(Hint: Eating often is not promoting health and well-being and is more likely than not to promote insulin resistance and fat gain.)
This brings us to one of the most excellent food lies ever sold by the big food and supplement companies: eating to "stoke your metabolism."
This counterintuitive advice is counterintuitive for a reason: because it counters what works!
Contrary to what the powers at be would have you believe, the human body is not designed to graze all day long like a cow.
We can find evidence by looking at our biology and why it is designed the way it is. Or we could just look at cows and what they eat to understand the differences between the two species.
A cow has to eat enough grass daily to fuel its massive body, which is why, as a grazing animal, it consumes most of the day. After all, grass is a low-calorie food, and so herbivores have to eat a lot of it to stay alive.
Compare this to another animal in the animal kingdom—the tiger.
A tiger can eat up to 88 pounds of meat in a single sitting. It is estimated that large wild predator cats eat around one 88-pound animal a week.
This means that a tiger finds prey, on average, once every week, at which point he will feast to his heart's content. Then he fasts until his next large meal.
A true carnivore.
And while humans aren't true carnivores—we are actually omnivores because we can eat hundreds of different forms of food—we have powerful carnivore tendencies, as is shown in the world our ancestors lived in for hundreds of thousands of years (the wild).
Our human ancestors would regularly go long periods between finding calorie-rich meat.
Sure, we would snack on berries, twigs, leaves, and anything else we could find as we spent our days walking through the vast wilderness (it is estimated that our ancestors walked about 13 miles a day on average).
But no tribe of 20-50 humans will survive on berries and leaves because the calories aren't there.
(Yes, that's a measly 7 calories in a cup of spinach. Remember that you would chew until your face is sore to get through a cup of raw leafy spinach.)
Now let's look at the calorie content of more calorie and nutrient-dense foods typically found in the natural human diet.
Suppose you wanted to get scientific with it. In that case, you could figure out the near-exact calories needed for a small tribe of 40 mixed-sex homo sapiens and then convert that into the amount of spinach and berries you would need to forage (in the wild, remember) to sustain life.
Then compare that to a diet with meat, fish, nuts, and seeds added in here and there.
But you don't need to do that because I did it for you.
To sustain 40 humans in the wild for a single day, you would need 12,814 pounds of spinach.
Blueberries do a bit better: 5,192 pounds of raw blueberries would be needed to keep alive 40 homo sapiens for one day.
(Disclaimer: the calories needed per day in these calculations are based on Harvard Medical School recommendations, which are probably overestimated. But still. You see the point, right?)
Our ancestors' survival shows that humans are designed to eat calorie-rich foods... and infrequently.
We do not graze. Therefore, we should not be snacking and eating six meals a day.
Anything or anyone that tells you to eat more is full of something (too much food, probably, which also means plenty of feces).
Be wary of any advice that recommends eating more often.
Your human body is designed to go extended periods without food because that is how your (and my) ancestors have survived in the wild for hundreds of thousands of years.
This is why the research on IF is nearly universal in showing the benefit.
Below we will see how the ways we are built—our biology—make fasting so darn good for us and, once implemented, naturally easy to maintain.
I've been following an IF eating style for over five years.
I used to do the 4-6 meals a day thing because that's what the Men's Health magazine said I should do.
I've also done 3 meals a day.
Finally, I've also done the "eat whenever I want with no rhyme or reason" style of eating (in a past life).
Now, with IF, I feel like I've found the light.
I bet you'll feel the same as me once you implement IF in your life.
I don't eat "breakfast" in the traditional sense.
My first meal is usually 6-8 hours after waking, sometimes later. This is when I eat breakfast.
My general overall health is the best it's ever been. (My blood work for life insurance yielded a "perfect" rating.)
I rarely feel the need to eat. I rarely get hungry.
I often have trouble eating earlier in the day since I'm now so adapted to a fasting schedule. It's hard to be hungry when friends want to eat earlier than my schedule is used to. (So I usually eat less.)
I now feel oodles better than I used to when I forced myself to eat breakfast each morning. When I used to eat breakfast in the morning each day because that is what we are all "told" to do, I would regularly "crash" soon after eating, feeling tired and groggy even though I had woken up only a few hours prior. No Bueno.
Hint: That's not how a healthy, functioning human body is supposed to feel a few hours after waking.
During my breakfast eating phase, I never really felt hungry in the mornings, but because I've been so conditioned by culture to eat in the mornings, it's what I did.
And it's probably what you do, too.
Did you know that breakfast means to "break the fast" and has nothing to do with the time you break that fast?
In our society, breakfast is something you do in the mornings. But that's not accurate.
(I suspect the cereal companies are to blame for this.)
The fact is, breakfast is your first meal of the day regardless of when you eat it.
My typical breakfast nowadays is 6-8 hours after I wake up. My next and last meal is usually 4-8 hours after that.
Then I'm done eating for the day.
And that's my intermittent fasting program. Simple. Concise. Works like a boss.
This schedule gives me an average feeding window of 8 hours a day, followed by a fast through the night (while I sleep) and into the next day's morning.
This 16/8 approach to fasting is known as the Leangains approach, credited to Martin B at leangains.com
(16 hours is the fasting period while 8 hours is the feeding window.)
By keeping my daily calories within this 8-hour window, I end up with a 16-hour fast daily.
To follow this fasting protocol, focus on keeping your daily calories within the 8-hour "window" after you break your fast. If you stop eating within 8 hours of breaking the fast, you’ll have a 16-hour brief each day.
It's surprisingly easy to follow once you get used to it.
And while I recommend you aim for 2 or 3 meals a day during your feed window, some proponents of the 16/8 method suggest you can eat as many meals as you want during that window as long as you stop after the 8-hour window has closed.
I am a bit suspect of this advice, and it doesn't come naturally to me, but it may work for some people. My preferred way to get the 16-hour fast each day is to skip breakfast, break the fast 6-10 hours after waking, and then finish my last meal within 8 hours of breaking the fast.
Of course, you should experiment and find what works best for you.
Ultimately, to get the benefits of fasting, your goal is to go as long as possible without food. The more you go without calories, the more help you will get.
So some days, you might end up with a 20 or 24-hour fast if you don’t eat until late in the day. While other days, you might start your feeding window a couple of hours after waking due to an early meeting or another life event.
As a general rule, the benefits from fasting come when your body has gone 12-18 hours without ingesting any calories. This is why the 16-hour fast every day is so powerful.
When I first started fasting, I tracked my hours closely to ensure I hit the 16-hour fast daily.
Then I didn't think about it, and my body did the rest.
Nowadays, my appetite tells me when to eat and not eat.
Starting, I suggest you track your feeding and fasting hours. This is just getting started because it helps you build the habit. (Here's a new app from Kevin Rose for that: Zero.)
Once you get the habit down, not only will you be amazed by how your appetite changes, but your new eating schedule will feel more and more natural as your hormones start to balance out.
When this happens, you'll fall into a natural rhythm, and all you'll have to do at this point is listen to your body.
Nowadays, this is what I do—I listen to my appetite and break my fast whenever it works for my day.
It makes food so simple, so easy, and enjoyable.
But make no mistake about what it took to get here; It takes time and patience.
Each person is different, so how hard it is for you will be different from how hard or easy it was for me or anyone else.
Just stick with it, and you'll reap the many rewards.
Now let’s look at a few of the benefits of intermittent fasting. Watch the video below for the scoop.
Fasting Makes Your Food SimpleWhen you are on a fasting schedule, you will start eating when your body tells you to eat, which usually averages out to 2 or 3 meals a day.
(Women do better on three meals daily in the research and empirical data I’ve seen. That said, I know females who do well on two meals daily, sometimes one. Experiment!)
Fewer meals simplify your food life, so you’ll spend less time eating, preparing, and buying food.
Another primary benefit of fasting, which contributes to helping you lose body fat while fasting, is appetite regulation.
When you fast, you balance out your hormones. This, in turn, reduces the amount of food your body craves and, thus, eats.
You are, simply put, less hungry.
This is all you have to do to get the benefits of appetite control while fasting: When you sit down for a meal, eat slowly, and your body will tell you when to stop eating.
Then stop eating.
The human body is a fantastic machine, so listen to it, and it’ll show you the way.
Regardless of what you’ve been told, eating more meals does not “spike your metabolism” or help you lose weight or burn fat.
Just the opposite, thanks to a hormone you’ve probably heard of called insulin.
Insulin’s primary job in the human body is maintaining glucose levels. It also manages storing glucose in your liver, glycogen (muscle), and fat cells.
Each time you ingest food, your body releases insulin to help manage the glucose (food converts into glucose in your blood) released in your bloodstream.
Insulin helps your body burn off glucose for energy and shuttle glucose into your liver, muscles, and, if there is extra, into fat cells.
Since most people eat far more than they “burn off” each day, they are unknowingly triggering a state known as hyperglycemia, in which they have extra glucose in their blood. This state results in insulin shuttling excess glucose into fat cells.
In a simplified nutshell, this is how you gain fat—more insulin and glucose in your body equals more fat gain.
Your body releases insulin and glucose every time you eat food (aside from outlier exceptions such as consuming ketones or MCT oil). Not only does this release of hormones make it difficult to burn off unwanted body fat, but there are more than a couple of health-related problems that come with constant and chronically elevated glucose and insulin levels.
Every time you release insulin and glucose into your body, you are making it more challenging to get your body into “fat burning mode” because you are telling it that you have excess food available, which then triggers your biology to store these extra calories in the form fat for later use.
(Hint: that's how our ancestors survived. Their bodies were great at storing fat when they had access to extra calories.)
Furthermore, from the meta-perspective of how your body and brain work together, if you are telling your body that you have food always available, as is the case when you frequently eat throughout the day, your body and mind are trained to keep the cycle going, which manifests in the form of being hungry and tired all the time due to your hormones running amok.
Remember: you and my ancestors lived in a world without modern food preservation, so when they were able to kill a mammoth or other large land animal, they’d eat as much as possible so that their body could store those extra calories in fat cells for later.
Extra calories stored in fat are a hunter gatherers' best friend.
Fat was a literal insurance policy for our ancestors since it gave them more time to find their next meal. Considering that food was varied and never guaranteed, as a hunter-gatherer, you’d want as much fat on your body as possible.
Of course, nowadays, fat is something we don't want at all.
But that’s because we (the lucky of us reading this, that is) live in a world where food is guaranteed. We will never starve in our modern world.
In a world where food is plentiful, there is no need for fat on our bodies since there are always calories available around us.
The fundamental health problem for humans relates to this mismatch because our biology has not yet adapted to the advent of agriculture and an always-available food supply.
This mismatch between our food supply and biology is also why we have a soaring obesity rate.
As we now know, our bodies are designed to store calories because it is trying to survive for later. So every time you eat food, your body will do its best to keep those calories in the form of fat cells because that is what it is designed to do.
Side note: For some people, it’s near impossible to get into fat-burning mode without drastic changes in the form of prolonged calorie restriction and fasting. This is why the more weight you gain, the harder it is to get off and the easier it is to gain even more weight.
No matter how you spin it, the more glucose and insulin you release into your body, the harder it is to control appetite, maintain ideal caloric intake, and burn unwanted fat stores.
Don’t be fooled by the outdated and misinformed advice about eating more often to “stoke metabolism.”
Please, please, please ignore the eat six meals day nonsense.
This is pure and utter nonsense meant to sell you products you don't need.
Repeat after me: The more I eat, the more fat I gain.
Repeat that over and over until you get it down.
These are the reasons why, as a general rule for health and longevity, you should always try to eat less food less often.
This leads me to the next benefit of IF: calorie restriction.
Countless studies are showing the longevity benefits of calorie restriction.
Humans are designed to eat fewer calories and less often than we do today.
Our ubiquitous access to food, coupled with the ever-declining quality of our food supply, is why we have an ever-growing obesity epidemic.
The typical Western diet is full of low-quality, empty-calorie foods. Take our already-poor diets and add the poor lifestyle habits of snacking, lack of movement, sitting too much, not getting enough sun, staying indoors, etc. You end up with a severe mismatch of the environment destroying the human species.
Compare this to our pre-agricultural ancestors that faced an inconsistent food supply due to a lack of refrigeration, farming, and modern food preserving methods, yet lived with excellent health, virtually no current disease, and a lot longer—on average—than people think.
(Our ancestor's low lifespan numbers cited in the media are averages heavily skewed by events such as trauma, for which there was no medicine or 911 to help, and infant mortality, which was very high and brought the numbers down a lot.)
Our ancestors' inconsistent food availability forced them to sometimes go long periods without food or with very little food.
This is one of the reasons that calorie restriction, like fasting, is a "healthy stress" to the human body.
Whether you want to lose weight or not, calorie restriction has many health benefits.
There are a few methods to practice intermittent fasting.
As we saw above, my preferred method is the 16/8 “lean gains” approach.
There are other methods, though, such as fasting for 24 hours at a time once a week.
Other methods of fasting include multi-day fasts every few months. This is something I plan on doing shortly. Either way, do your research and consult a doctor before trying anything like that.
From empirical evidence I’ve seen in myself and others, the daily 16/8 fasting model seems the most popular and easiest to start with.
All this being said, there is no right or wrong way to fast.
The first thing you want to do is reframe your mental model of food and meal frequency.
These few changes themselves can have life-changing effects.
It can be hard to get out of the “I have to eat” mindset, but until you feel the other side for yourself, you'll never know what you might be missing out on.
(Trust me: you're missing out.)
A final note on eating and muscles.
You don’t have to eat all the time, and you shouldn't.
No, your muscles and gains won’t waste away.
Numerous studies correlate fasting with growth hormone release. (Study.)
There is also research that fasting has a protein-sparing effect, so if you are worried about “wasting away” in terms of losing your gains, this is unfounded. (Study.)
The improvements in insulin sensitivity you get from fasting, which is one of the most significant overall benefits of fasting, improve the production of muscle-building hormones such as growth hormone and increase your body’s general management of hormones—insulin and cortisol being the key players.
One thing I hope you take away from this piece is this: Re-frame how you think about food.
Food is something you should eat only when you are hungry—and also something you should skip eating even when you are hungry, so you can get the benefits.
Get out of an eating mindset and get into a not eating mindset.
Remind yourself that every time you skip food that you typically would have eaten, you have performed a healthy “stress” for your body. And you are now more likely to live longer and one step closer to controlling your appetite rather than it controlling you.
Eat less food less often and watch as your health and results improve like nothing else you’ve ever done in your life thus far.
It is that amazing.
Now let’s look at one last “fasting technique” near and dear to our hearts here at Wild Foods.
I have a question about intermittent fasting and butter coffee. I’ve been trying not to eat after 6 in the evening, having my butter coffee the following day, and not eating till about noon. I’ve asked you before, and you said putting protein powder in my coffee would break the fast. I have been using your oils and butter in it, but I want to know is does your raw chocolate powder and vanilla powder (both of which I have and use) break my fast. I love it for its flavor and antioxidants. I use a bit of Lakanto or stevia, zero glycemic, as a sweetener.
So I’m a bit confused about what breaks the fast. I know my cup of coffee has some calories, mainly from the fat, but it sustains me till noon.
Anything sweet is going to break your fast much easier than protein. Fat is ideal for not breaking a short, but even certain kinds of dairy fat can contribute to breaking it, so the type of fat does matter. (Why we love butter and MCT oil so much.)
From some recent research I’ve seen by a Dr doing solid IF research, he has figured out a number that he thinks will give one many of the benefits of fasting while still consuming a small number of calories, which is somewhere around ~500 a day if I recall correctly.
Based on this, and from what I’ve seen, I would recommend going with your whey as you have, as well as vanilla powder and cocoa as even more safe options while trying to avoid sweeteners as much as possible.
Even though something like stevia or xylitol can be no sugar, your brain interprets them the same as ingesting sugar, so you can be prone to an insulin-like response, thus knocking you out of a fasted state.
Colin, excellent timing for me with this article as I’ve been fasting for the new year. I don’t eat after dinner (between 5-6), have my butter coffee the following day, and don’t eat till noon.
Let me ask you, to get more protein in because of the weight training I do, does a scoop of whey in your morning coffee technically break the fast? I know you’ve mentioned your wild whey being good in coffee.
Technically, you won’t be straight fasting with then protein. It’s typically fat that seems less of a “break the fast” response. That said, there’s some exciting research from a fasting researcher that has a style of fasting based on eating a small number of calories a day, say around 400-500, while still showing similar benefits to fasting with no calories.
I feel that you should always aim to go as low calorie, low protein, and ZERO carbs as possible when fasting, but even if it’s not ZERO does not mean you aren’t getting benefits.
Again, progress is not perfection.
I have been fasting for 20-24 hours once or twice a week for the last year and like it, but I have always been annoyed with juggling my workouts to avoid fasting on the same day.
I am looking forward to trying the 16/8 plan. Out of curiosity, do you exercise inside your 8-hour eating window or outside of it?
Start eating your first meal after your workout. Your life is forever changed.
That’s probably the single most excellent training-based benefit I got from IF. So much better to train without food in my system. Tim Ferris also talks about this in his recent podcast.
Butter coffee is perfect if you are just starting fasting because instead of quitting cold breakfast turkey, you get clean calories each morning from grass-fed butter and MCT oil in a delicious frothy butter brew.
These fat calories will help you transition from a typical whole food breakfast to a fat-dominated liquid breakfast.
And this can be the stepping stone that will help you eventually wake up to nothing more than a glass of water.
Even though I can now wake up to just a glass of water each morning, I start my day with the Wild Butter Brew because it's delicious and because I like the pure fat calories to help me perform at the top of my game.
I use the same 8/16 fasting model but don't count my morning mug as breaking the fast.
So I wake up and have a mug of Wild Butter coffee. Then I work for 8-10 hours. Finally, I eat my first meal of the day.
By ingesting only fat from pastured butter and MCT oil, I don’t officially break the fast the way I would if I was eating carbs and protein.
This also helps train my body to utilize fat for energy instead of relying on glucose from quick-ingesting carbs and protein. (Keyword: Fat-adapted)
The MCT is unique because it is quickly burned off for fuel and helps put your body into a state of mild ketosis. With the combination of ketones and pure pastured butter fat, this fuel will help prevent you from getting tired in the early afternoon, a common occurrence for those that get into fasting.
Butter coffee in the morning will provide many of the benefits of fasting while also giving you fuel to keep you on top of your game. It will also ease you into fasting and give your body time to adapt.
After a while, the idea of eating whole food in the morning will seem bizarre to you. Around this time, you should experiment with going without coffee or food in the morning.
It’s beautiful when you can wake up each morning and go your entire day without food or stimulants.
I wish you the best on your fasting journey. Let me know if you have any questions or comments. I’ll help where I can.
Before attempting any new diet or fasting protocol, please consult your doctor. All of these methods are to be used at your own risk.
I hope you’ll become interested enough in IF to give it a shot.
It is life-changing.