We know it...
Everybody is talking about the keto lifestyle and its benefits - weight loss, energy, lower blood sugar levels and inflammation, mental clarity and many more.
If you are already familiar with keto, you probably heard about ketosis. But do you really know what it is?
In this article, I'll explain what is ketosis, what is metabolic flexibility and how you can get your body into this amazing metabolic state.
Ketosis: a natural metabolic state
We can describe ketosis as a metabolic state in which our body uses ketones instead of glucose to maintain all the processes that happen internally.
How does this happen?
When our carbohydrate intake is very low, our body cannot use glucose as the main source of energy so it starts using stored fat as a primary fuel. The liver transforms fat into ketones so we can use them to survive.
That means that ketosis is a physiological state, not a pathological state or a health issue. Humans, historically, have been in ketosis for long periods of time due to famines and the lack of high carb foods like fruits and tubers - something that was common in winter or in some places around the globe like glacials or very cold continents, where vegetables don’t grow or fruits are only available during warm seasons.
Hunter-gatherers could spend long periods of time only eating meat - we were scavengers - and also fasting for days, another mechanism that can lead our bodies into a ketosis state (If you want to know more about intermittent fasting and how it can help you achieve your health goals, read this).
Nowadays, tribes like the Inuit that live in the arctic, follow a diet that is mostly meat (around 98% of the total calorie intake) from animals like whales, seals, bears… It's difficult to find vegetable food sources most part of the year because of the extreme weather conditions. So they are really well adapted to ketosis.
Ernesto Prieto Gratacos is a scientist from Buenos Aires, Argentina, who has been studying the link between nutrition and cancer. He recorded a documental called “Cancer and civilization” that shows how some tribes that still live as hunter-gatherers don’t have metabolic issues and very low rates of modern diseases like cancer or diabetes. One of those people is the Eskimos living in the arctic, eating a high-fat diet mostly based on animal foods.
Western diets are very high in carbohydrates. Not from tubers or fruits that grow seasonally, but from refined carbs mainly from cereals and artificial sugary foods all year round (bread, pasta, pastry, sweets…).
This is leading us to a pandemic of obesity, diabetes and other metabolic diseases. The western diet is killing people thanks to inflammation.
What are the benefits of being in ketosis?
Some of the benefits of being in ketosis are:
- More energy for brain and body
- Focus and mental clarity
- Weight loss
- Better skin (also helpful for acne treatments)
- Improved insulin sensitivity
- Decrease risk of heart disease
- Improve metabolic flexibility
You may have heard of some (or all) of them already.
But the one that is less talked about is the latter: metabolic flexibility. So let’s dive into this concept that may be the key to good metabolic health.
What is metabolic flexibility?
When it comes to metabolic health, we must be aware of the importance of being able to use either glucose or fat as fuel in our bodies. That’s what we call metabolic flexibility, as the capacity of our body to use two different energy sources indistinctly when needed.
This was “easy” when we were hunter-gatherers because we only ate the food we could depending on the season or place we lived, but it all changed on the Neolithic.
Agriculture led us to a very different lifestyle: we stopped moving from one place to another, we had food available most time of the year in the form of cereal, pulses and tubers, and also communities started growing thanks to this “progress”.
Jared Diamond, and historian and anthropologist, wrote this polemic article called “The worst mistake in the history of the human race” in which he talks about the problems that agriculture brought us.
I know it is a very controversial article, but the thing is that those changes on the human diet could lead to some of the illnesses, like type 2 diabetes and obesity.
That’s why the concept of metabolic flexibility is so important. Now that we have large quantities of food at our disposal (which is amazing because we do not have to go hunting or own a farm), we go to the supermarket and buy everything we need to keep our energy levels up. If you're following a standard European or American diet, this means a lot of processed carbs and sugars.
This blocks our metabolic flexibility - the capacity to use different energy sources in an effective way. When you're metabolically flexible, your body doesn't have to keep asking and craving for food every 3 hours because it doesn't need to. It burns fat for fuel.
And that’s why it's so important to include periods of ketosis in our lives, to give our body a push to not relax, to help it burn fat and also to give our pancreas a rest. When you're in ketosis, your body starts to get used to burning fat for fuel and over a period of time, your metabolism will burn both dietary and stored fat for energy more effectively.
Can I also be on keto for a long time?
There is usually no problem on being on a keto diet (or in ketosis) for long periods of time if you have a health condition that requires accurate management of your carb intake, like epilepsy, type 1 diabetes or some types of cancer - or if you feel good while doing it.
I'd recommend sticking to a lifestyle where it is ok for you to be on ketosis for some period of time during the year. That would give you this metabolic flexibility that is so important for our health.
How can you get started on a keto diet?
My recommendation is to start slowly, reducing first all the processed high-carb foods like bread, pasta, sweet treats and then reducing natural high carb sources like potatoes, sweet potatoes and fruits.
So, when you start reducing these high carb foods, you have to start increasing your intake of healthy fats. There are many delicious foods high in healthy fats - avocados, wild fish (like sardines and salmon), coconut oil and milk, extra virgin olive oil, organic dairy (if you tolerate it), natural nuts and seeds, and our keto chocolate bars which are super high in healthy fats from MCT and organic cacao.
The idea is to get your energy from 65%-70% of healthy fats daily and maintain your net carb intake to 5%. Commonly, this means eating about 20g of net carbohydrates per day to stick into a ketosis state. But don't take this 'to the T'. Your daily macros will depend on your health goals and levels of physical activity. Just remember that to achieve ketosis, you have to aim to keep your net carb intake low.
The ketogenic diet is a great tool to manage many health conditions, including the ones caused by inflammation, and increase your metabolic flexibility for overall health. If you want to be fully keto-adapted, meaning to let your body only run on fat, I'd recommend you to follow a ketogenic diet for at least 6-8 weeks so your body can use fat as the primary energy source effectively. However, this is a rough estimation. The time you will need to get keto-adapted depends on your metabolic health.
Please note that being in ketosis and keto-adapted is not the same thing. You can reach the ketosis state after a few days or first weeks on keto by reducing your net carb intake. Keto-adaptation or fat-adaptation is a longer-term state of ketosis where your body is consistently burning fat for fuel as its main energy source due to the lack of carbohydrate intake.
Once your body is using fat efficiently, it will be far easier for you to go back to ketosis if you wish to start introducing healthy carbs to your diet. Hence, the metabolic flexibility that I was talking about.
Give your body the opportunity to learn how to use fat as fuel and see how it makes you feel healthier, stronger and younger!
Other blogs you might enjoy reading:
- Ketogenic Diet & PCOS
- LCHF Dietitian Noor and her Keto journey: Why she started and tips for beginners
This article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or health provider with any questions you may have.