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  • Writer's pictureIrekZareba

Metabolic Flexibility - Restore Natural Body Ability and Achieve Your Health Potential!

In this article I will talk about something which for many of us can be a simple and powerful solution to cure many health problems and also how to feel amazing in your own body. The concept of Metabolic Flexibility I have first heard of thanks to great people like Dave Asprey and Mark Sisson. Something I was immediately intrigued about and tapped into a few years back and ever since I have been experiencing higher and steadier levels of energy throughout the day and without thinking about food too much!

And I assure you, it feels so good!

What if Food is the Cause of our Health Problems - the Pandemic of Eating?

Majority of today's health problems are due to the fact that we have lost our natural ability to be metabolically flexible due to high dependency on carbohydrates. It has become the main fuel source, in every frequent meal we consume which together with a sedentary lifestyle creates the disastrous combo for our health! The point to start from is to understand that we are hybrid organisms - designed by nature to operate both on fat and glucose. After the agricultural revolution and today's caloric dense processed food we lost that ability - literally.

This situation in many cases leads to the point where the body is ‘craving’ mainly this source of energy and signaling in the brain in the exact same way whenever sugar in the body is being used - ‘give me more sugar’! This way we developed sugar spikes and drops which force us to eat every 2, 3 hours. This leads to the condition of the body where we are under constant pressure to be around food all the time.

The point to mention is that high carb dependency without proper utilization of stored energy - due to physical inactivity, can develop insulin resistance (body cannot keep up with the amount of sugar anymore), high inflammation, type 2 diabetes, obesity, Alzheimer, cancer to name a few.

The list unfortunately is much longer…

Metabolic Flexibility as a Potent Tool for Daily Stress Management

The ability to efficiently adapt metabolism depending on demand or supply is known as metabolic flexibility.

For many of you it can be something you have never heard of. But for our genes it is something that is written in their blueprint. Hence it's very natural and something we should be easily wired to on a day to day basis for optimal body management. It is the ability to use by the body different sources of fuel regardless whether there is food available or not. Metabolic flexibility is achieved through developing resilience in the body to not be driven by hunger. The flexibility here means that the body is able to shifts seamlessly and utilize energy from different fuel sources available to it in any moment, i.e. from fat on the plate and stored fat in the body, carbs on plate, glucose and glycogen in the liver and muscles, glucose from protein (through gluconeogenesis), and ketones.

Every excess of any macronutrient is being converted into triglycerides and stored as fat in the body (hence moderation is a key unless your goal is to gain more fat tissue). Point to remember when it comes to carbohydrates is that it's being converted in the liver into glucose which can't stay in the bloodstream in such from for too long (on average there can be only 5g of glucose present in the body at the time). When cells become full, then the liver converts remaining glucose further to glycogen and stores it in muscles. If they are full then some amount can be stored in the liver itself. If that sugar storage reservoir becomes full then the excess of glucose is converted into triglycerides and transferred via LDL cholesterol to white adipose tissue to be stored as fat (i.e. future energy source for the time when food is not present). So to utilize that stored fat - the opposite process must happen. We need to deplete the body from glucose in the bloodstream first and the glycogen too!

How? The movement - hence the importance of exercising!

In the time of our hunter-gatherer ancestors, these conditions were very easy to achieve (they were constantly in motion to search for food and they could go days without it! - I am not saying that this is an ideal situation for us now, but it simply shows human resilience and what our body is capable of).

That becomes nearly impossible in sedentary civilization watching tele and with abundance of food at the hand reach around the clock! Dependency on carbs and constant snacking leads to inability to use other energy resources available in the body. This directly impairs our mitochondria function (power plant for cells) and therefore the entire energy efficiency mechanism. Not to mention that even without being surrounded by predators like back then, we seem to be more afraid and more insecure than ever!

Ironically, it looks like our comfort has became our fate.

For that to change, we need to create ‘similar’ conditions to the ones like in the past to be ‘uncomfortable’ again. The good news is that we don't need hunting neither predators to achieve that anymore. But still this is going to be a challenge for many of us and that’s absolutely OK!

Just know that breaking from that dependency on sugar requires some time necessary to train the body - literally - to regain the ability to burn fat for fuel effectively! In some cases it might take up to several weeks.

Before we get to that, here are some benefits of being Metabolically Flexible for you to consider:

  • Greater health and well-being

  • Supporting body in sustain energy production

  • Fewer cravings

  • Improved fat-burning

  • Developing greater resilience

  • Slowing down aging process

  • Better weight maintenance

  • Lower odds of developing a metabolic disease

  • More consistent, healthy glucose levels

  • Improved sleep

  • Optimized workout performance

How to Break the Vicious Circle of Carb Dependency?

To establish metabolic flexibility we need to allow the body to learn how to be fat-adapted again. There are few strategies available to restore the natural order. One is no food intake for prolonged periods of time, known as fasting.

Second, eating healthy fats and moderation of protein in the absence of carbohydrates, known as ketogenic diet. Both are effective, but can be very challenging for many at the beginning!

That’s why if you have never tried both methods I would recommend a safer option and somewhat the combination of the two above - Intermittent Fasting, where the daily feeding window is restricted to a certain amount of hours (that means no 3 meals a day anymore, usually two, sometimes even 1, depends on how well you adapted and your energy expenditure on particular day). The popular IF is 16 hours (sleep counts too) to 8 hours of feeding window.

Start where you are eating the same type of meal but just squeeze bit by bit your eating window. See how you feel. Then gradually reduce amount of carbs (especially those processed once!) and introduce healthy fats for greater benefits and to discover what is possible for you in the keto world. The best part is that this very simple and flexible strategy is entirely for free! The whole process might take up to a few weeks. I highly recommend Mark Sisson's book ‘Keto reset diet’ for deeper dive and to facilitate the change.

Very important to manage the stress levels properly, as this leads to craving for more food. Also too much cortisol leads to break down of the muscle tissue which then is being converted into glucose. And whenever insulin is secreted to absorb that glucose (the major fat storage hormone) your metabolic switch is set to store fat - you cannot store and burn fat for energy at the same time.

Now, I do understand your potential resistance to this idea as I was there too. I remember when I started my bulletproof coffee mornings, I had a lot of fear around putting butter and MCT oil together due to false cholesterol stories out there connecting nutritional fats with causes of heart diseases etc. This is normal, as to conquer our beliefs in this process is inevitable.

Now there is no fear anymore, my body and brain love it and I am thriving on that! In fact bulletproof coffee (I use decaf these days or in a form of herbal tea too) it's a great hack and place to begin the restoration process with.

Bulletproof Coffee Recipe (from the founder, Dave Asprey)

  1. 1 cup of your favorite coffee

  2. 1 teaspoon - 2 tablespoons of MCT oil

  3. 1-2 tablespoon of grass fed butter or 1-2 teaspoon of ghee (clarified butter)

  4. Blend together for 20-30 seconds

The idea is to replace the regular breakfast with this super tasty drink. This is a fasting mimicking remedy, which prolongs the fasted state of your body after night of sleep (hopefully) and helps you maintain fat burning mode till lunch time or even longer if you wish.

Then you can have some of healthy carbs from whole food sources later on, especially if the day is super active. The safest option are the ones with low glycemic index - like berries, to avoid high sugar spikes. But the best strategy is to test different foods through continuous glucose monitor to check your body responses to particular sugar source as this varies from person to person (eg. each of us have different reaction to the rice).

Once you discover how great it is to feel with no food, or after ‘no carbs’ mornings you will never go back. This is thanks to ketones - energy molecules converted from fat in the liver which then fuels your brain and muscles.

Now, always the best strategy is to consult such changes before the start with your physician.

Also Intermittent Fasting might not be best strategy if:

  • you have difficulties to control diabetes

  • you are under 18

  • you are pregnant

  • you have chronic heart issues or kidney disfunction

  • you have history with disorder in relationship with food (eg. anorexia, bulimia, binge eating)

  • you have low BMI index

  • you have been recently sick

Remember the goal is to free yourself from carb dependency and to become a highly performing metabolically, healthily functioning human being - and not the opposite. Be smart and start with small steps. As a new thing for the body it is going to be an additional stressful situation - here in the short run, but it will become very beneficial in the long term health. So treat your body with respect and after each change always monitor the way you feel.

Wish You Many Successful Discoveries!

If you want to change the way you feel and live a healthier and happier long life just get in touch.

In my coaching sessions I can facilitate that process and make it super easy for you!


Olson KA, Schell JC, Rutter J. Pyruvate and metabolic flexibility: illuminating a path toward selective cancer therapies. Trends Biochem Sci. 2016;41(3):219–230.

Dave Asprey interview with Mark Sisson in Bulletproof Radio

For Deeper Dive into Metabolic Flexibility:

Interesting Oxford Academic article ‘Metabolic Flexibility as an Adaptation to Energy Resources and Requirements in Health and Disease’

Mark Sisson’s book - Keto Reset Diet

Dave Asprey's book - Bulletproof Diet

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