Fat Adapted: The Beginner's Guide

Fat Adapted

Becoming fat adapted is essential for optimal energy usage. If you’re new to the world of low carb or ketosis - you may have heard the term “fat adapted” thrown around - but what does it mean, how do you know if you are - and how can you do it better?

I’ll break it all down for you.

What Is Fat Adapted?

Fat adapted is the term we use to describe someone who can efficiently burn fat stores from their body instead of being limited to being only able to burn carbohydrates.

This is an important part of metabolic flexibility as it opens up your fueling options and allows you an array of ways to nourish your body depending on your goals. 

But - you’re probably wondering - why the heck is being fat adapted even important?

Great question…

Why Becoming Fat Adapted Is Important

Fat Adaptation is an important part of being human. Before 24/7 grocery stores, Uber eats and our everything-on-demand culture, humans ate when and whatever they could in the past.

They would utilize whatever food or energy source they could find. Berries in the woods? Great. A nice mammoth steak? Awesome. A slice of pizza from Home Slice? If they could time travel and find one - you bet they would.

But that meant that they were efficient energy machines. They could switch in and out of using whatever energy source they had.

Now - with most standard American diets being carb & sugar heavy, most people only can burn carbohydrates. If you remove those from their diet - they feel all sorts of ways - which is not how it’s supposed to be!

Being Fat Adapted is Important For Several Reasons

Easier Weight Loss

When you’re fat adapted - your body shifts from burning external fuel to literally burning fuel on your body (fat). This makes fat loss remarkably easier because you don’t have to consume so many calories for your baseline exertion - so you’re not fighting such an uphill battle!

Improve Fitness

Any endurance athlete will tell you that “bonking” (or running out of fuel) is the absolute worst. While your body can only hold glycogen stores for 45-90 minutes, by becoming an efficient fat burner - you can both limit your dependency on carbohydrate burning and decrease the risk of bonking.

Clearer Thoughts

Once you’re fat adapted, many people report having cleared “brain fog” and feeling better across the board. This is because your brain literally runs on ketone - so if you can upgrade the fuel that your brain runs on - it’s no wonder that it’s operating more efficiently.

Disease Mitigation

It seems that there is some correlation between fat adaptation and disease mitigation. Either way, when heart disease and diabetes are two of the top leading sicknesses on our population - fat adaption is an easy way to lower risk factors on both of them. 

Fat Adapted vs. Ketosis

Fat adaption is different than ketosis. Being in ketosis is a specific state you’re in - where you’re fat adapted is more of an extra tool in your tool belt.

Being fat adapted is more than just a state. It’s a capability your body has to be able to kick in and kick out of so you can ideally be in ketosis most of the time. Then, post workout - or on a random cheat day - have a carbohydrate focused meal - burn it - and be right back to burning fat the next day.

Fat Adaptation can give you a level of flexibility that can help you maximize your body and training while still burning fat and feeling good.

How to Become Fat Adapted

If you’re trying to become fat adapted, here’s a few times:

Starting Eating a Low Carb Diet

Becoming metabolically flexible is a great thing and it’s one of the reasons we promote real food-low-carb diet here. Paleo and keto are both good options here, but you can choose any low carb diet. 

This will increase your insulin sensitivity and keep your glucose levels in check - both of which are absolutely necessary if you want to start burning fat.

Take MCT Oil

MCT oil can help you burn fat more efficiently than other fats. If you’re having trouble kicking into fat burning mode, these can help.

→ We recommend these from Perfect Keto.

Eat More Fat

It’s hard to become fat adapted if you’re just feeling like you’re starving all the time. You can fix this by just eating more fat.

You need to make sure you’re consuming enough protein, but once you knock this out - you can supplement your satiety needs by adding fat and you’ll notice slowly that you’re becoming more and more efficient at burning it.

Fast Regularly

Again, fasting is one fo the best ways to train your body to become fat adapted. By limiting both carbohydrates and calories your body begins to drop into ketosis when it has exhausted your glycogen reserves in your muscles.

This trains your body to become more efficient at utilizing fat for energy, especially if you can extend the length of time you’re fasting each time.

Supplement with Exogenous Ketones

If you find you’re running into adaptation issues like the keto headache, consider supplementing with exogenous ketone.

→ These ones from Perfect Keto are our favorites.

Do Resistance Training

Lifting heavyweights and sprinting can improve your insulin sensitivity and make your fat adaption process much, much easier.,

Limit Carbohydrates When Not Training

While this goes in hand with our low carb diet recommendation, if you’re going to have carbohydrates, have them while working out or immediately after training. It will do wonders to help you recover without ruining your fat adapted state.

Using a Meal Plan When You’re Fat Adapted

Many people find it helpful to start with a meal plan to work towards becoming fat adapted.

Having a meal plan will help you create a plan and stick to it when you’re thinking about what you 

Try a keto meal plan here

Try a low carb meal plan here.

If you’re diet agnostic, you can check out all of our diet meal plans or just start with a generally healthy meal plan here.

Other Keto & Low Carb Related Reading

Low carb vs. Keto

Understanding Ketone Bodies 

What is Keto Headache

Does Coffee Break a Fast? 

Other citations & reading

Other sourcing material you should read

About the Author

Joel Runyon

Joel Runyon is the founder of Ultimate Meal Plans. Joel is an ultra endurance athlete and entrepreneur. He's also the founder of Ultimate Paleo Guide and is the founder of IMPOSSIBLE ® - a lifestyle performance brand helping people push their limits in fitness and life.