Fasting is like meditation for your body. For the next few days, we are going to dive into the science and benefits of fasting.
In today’s society, most people lack control. They don’t control their emotions, their reactions or their health.
The epitome of this is the tyranny of food — especially carbohydrates.
Look around. Most of the world revolves around food. Wherever people go they carry a snack with them, lest they have to be hungry for a few hours. People structure their days around the prototypical 3 meals. And to them, deviating from the typical schedule sounds crazier than defying gravity.
But this isn’t normal. It was only recently that we domesticated animals and grains and had constant access to food. Homo Habilis, the first Homo, emerged 2.8 million years ago. It’s only in the last 10,000 years that we had agriculture — that’s only 0.3%.
If evolution of the Homo species was on a yearly calendar, it would only be on the last day of the year — New Years Eve — that we developed agriculture.
Before this period humans ate intermittently. We had to work for the food — we couldn’t stroll into any random coffee shop and pick up a pastry. Kill or be killed.
Instead, humans would be fasted all day while they hunted and gathered, and they would eat afterwards. They had to work for their food…literally.
The modern interest in fasting is attempting to get us back to this evolutionary norm.
Fasting is the best first step to take back control of your life. From a stoic perspective, how can you take back control of your life if you’re always at the whims of your hunger?
Fasting is your rebellion. The best way to take back control of your health and your life.
The Science of Fasting
Dietary recommendations have destroyed your health by changing both:
- what you eat and
- when you eat.
If you want to improve your health, you need to restore both to your evolutionary ways.
Let’s jump right in. Why does fasting work?
Fed vs Fasted States
You can only get energy from two sources: Food or body fat. But you can’t get energy from both at the same time.
When you’re getting energy from food, this is called the fed state. When you’re getting your energy from body fat, this is called the fasted state. Insulin and glucagon — two hormones — regulate this process.
Your body isn’t used to such a quick hit of energy because for most of history we were not eating pringles. So this puts you in what I referred to above as the fed state — but on steroids (insulin signals this).
After you eat junk food, your body has abundant energy available and will only burn that for energy instead of your stored body fat.
Because we’ve been brainwashed to eat this junk all day long, most people are perpetually in the fed state.
They are never burning body fat.
Intermittent Fasting: How to Enter the Fasted State
It takes ~12 hours to lower insulin far enough to actually burn body fat and entered the fasted state. But most people are eating all day, and not giving their bodies enough time to lower insulin levels and burn body fat.
Even after their 8 hours of sleep most people shut this natural process off by eating a high carb (also translated to dessert) meal first thing in the morning.
To counteract this, many have started to intermittent fast. Instead of shoveling food into your mouth every waking hour, people purposefully restrict their eating window.
The most common way people do this is by skipping breakfast and eating lunch and dinner.
This leverages your 8 hours of sleep time to make the total fast easier. If you just eat lunch and dinner from 12pm – 8pm for instance, you’ll fast for 16 hours.
This is pretty much the exact opposite of what all American’s do given most people still believe “Breakfast is the most important meal of the day”.
In fact, the early morning is when insulin and ghrelin levels (the hunger hormone) are the lowest and you should be fasting. The only reason some people are so hungry in the morning is because they’ve trained their body to expect a massive hit of high glycemic energy right when they wake up. But French Toast + OJ every morning is the fastest way to get diabetes.
Whereas if you fast until lunch, your insulin levels will fall sufficiently to burn your stored body fat.
This has immense benefits I’ll get into below.
How Do You Produce Energy Without Food?
When there’s no food around your insulin levels fall and glucagon levels rise. This pushes you into the “fasted state”.
When you’re in this fasted state, your body has a few priorities. First of which, is ensuring a constant supply of energy from your brain. Even under fasted conditions with no exogenous glucose available your brain needs glucose to function.
In response to the high glucagon : insulin ratio your body does a few things:
- Shuttles stored liver glycogen to cells for energy. Most people store approx 100-150 grams of glycogen in the liver (this is glucose that you store)
- Start to break down fatty acid molecules into glycerol and glucose, to power the brain. Yes you read that correctly. Body fat can be broken down into sugar.
- Breaks down deficient and old proteins into glucose via gluconeogenesis to power the brain. This protein is not muscle cells. The protein that breaks down is old damaged protein and skin and intestinal lining.
- Shuttles body fat to the liver to make ketone bodies (like beta hydroxybutyrate). Ketone bodies will be used to provide ~10%-20% of the energy your brain requires.
There’s no reason to fear fasting. Your body stores a tremendous amount of energy at any given time in the form of body fat and liver glycogen. This is a great analogy from Ben Bikman below.
Imagine you are a fuel tanker carrying 1000s of gallons of fuel. But when your small gas tank runs out, you still need to go to the gas station. This is how your energy system functions when you’re not burning body fat.
Instead, imagine the tanker could burn all the fuel it carries. This is your body fat. You carry 1000s of calories of energy around in the form of fat, but never allow your body to burn it.
When you enter the fasted state, this changes.
This is where all of the benefits of fasting come.
Entering the fasted state allows your body to burn body fat for energy and switch over to ketones which are a better metabolic fuel.
Tomorrow, we will dive into detail on my favorite type of fasting and its benefits.
Onward.
