Do you know what it means to be “fat adapted”?
When you’re in this metabolic state, you’re able to burn your stored body fat reserves for energy.
That means you could be using your lovehandles to power through your high intensity workout instead of a smoothie.
Being fat adapted also reduces your body’s cravings for carbs. And it helps you reach fullness faster during mealtimes (and keeps you fuller longer) so you eat fewer calories during the day.
Fat adaptation kind of sounds like the unicorn of diets.
So, is it for real?
To find out the truth and to dispel some myths, we’ll go over everything you need to know about being fat adapted in today’s guide.
I’ll dive into topics like:
- What it Means to Be Fat Adapted
- How to Become a Fat Burning Machine
- How Fast You Can Achieve Fat Adaptation
- How to Tell if You’re Fat Adapted
- The Difference Between Ketosis and Fat Adaptation
By the end of this guide, you’ll have all your questions answered and you’ll know if a fat adapted state may be right for your body.
To start, you should know the definition.
Most people, including those who are pre-keto, are not naturally fat adapted because the traditional Western diet is so heavily anchored in processed, carb-based foods[*].
This means that instead of relying on a stored fuel source such as fat, sugar-burners run off a constant supply of carbs (aka sugar).
When the supply dips too low, you’ll experience low blood sugar, which may bring symptoms such as lightheadedness, carb cravings, dizziness, the inability to focus and your usual sugar crash.
To fix the issue and maintain sustained energy levels, your body needs a steady stream of carbs. But that’s also where the problem begins.
See, once carbs hit your system, they send your blood sugar levels through the roof.
Your body works overtime to combat this flood of glucose by sending out more insulin, a hormone to help sugar get out of your bloodstream and into your cells. Consequently, your insulin levels rise.
With too much insulin floating around in your bloodstream, your brain’s chemical signals are all thrown off — including those that let you know you’re full.
This explains both why you tend to overeat and why you always feel hungry.
Your body craves more carbs and creates a downward spiral that leads to unwanted weight gain — especially around your stomach and hips, which may be why it’s so difficult to lose fat from these areas.
Sound like what you’re dealing with?
To find out if you’re a sugar-burner for sure, answer yes or no to the following questions:
- Do you experience a “hangry” sensation (i.e., irritability when you’re hungry) when you go more than 4-6 hours without eating?
- Do you snack between meals, throughout the day and into evening?
- Are you having trouble feeling full or satiated after meals? (If you’re unsure, the next question will help you answer both)
- Do you crave something sweet after meals despite feeling uncomfortable or bloated?
- Do you prefer carb- and sugar-rich foods like bread, pasta, cookies or ice cream?
- Do you struggle to lose weight around your midsection?
If you nodded your head yes to more of these questions than no, you’re most likely a sugar burner.
Don’t you think it’s time to switch to a better fuel source?
One that not only helps you zip through your day but also burns your stored body fat for energy too?
Instead of constantly relying on an influx of carbs, you could use the excess fat on your body as a steady source of fuel.
That’s fat adaptation in a nutshell.
Why Fat Adaptation is Different
Your body is capable of metabolic flexibility, or switching between using sugar or adipose tissue (aka stored fat), to perform all its daily functions.
To get to the glorious point of fat adaptation, you need to tackle three steps:
- Limit the amount of carbs you eat
- Eat a larger portion of healthy fats
- Monitor your intake of high-quality protein
By reducing your carb intake, your body will burn off all your remaining carbs and glycogen stores right away. Then it will tap into your excess fat stores to give your metabolism and energy the real boost you need to combat any Monday.
Combining protein and high fat will keep you feeling full and energized so you won’t experience those pesky energy crashes at your desk, unwanted cravings for candy bars or that constant growl of hunger in your tummy.
When you’re fat adapted, you’ll be able to go 4-6 hours between meals without ever feeling hungry.
And the icing on the low-carb cake is you’ll finally be able to get rid of that stubborn belly fat that hasn’t budged since freshman year.
Now it’s time to put that spare tire to work.
To become a bona fide fat burning machine, you need to transition to a fat adapted state.
This is just a fancy way of saying you’re going to teach your body how to burn fat for energy instead of relying heavily on glucose and carbs.
Here’s how to do that: slowly start reducing your intake of foods high in both carbs and sugars and replace them with healthy fats, high-quality proteins, and a much smaller amount of carbs for necessary dietary fiber.
By small amount, you shouldn’t go from 100 grams of daily carbs to just 10 grams overnight.
You’ll want to gradually reduce your carbs while also adding more fats and proteins to your diet. This will help eliminate sugar cravings during your withdrawal period (yes, you’ll have one) for a much smoother transition.
Again, if you try to tackle this cold turkey, you’re going to feel unwell for quite some time. And don’t be surprised if this hiccup leads you right back to eating more carbs.
The key takeaway here is to go slow and steady. Reduce carbs little by little. And simultaneously add in more healthy fats and protein.
Do this and you’ll be fat adapted in no time.
Wondering just how long that takes?
I get it. You want to be fat adapted like yesterday, right?
Well, it may take a bit more time than that. But how much more time?
Good news: It can take as little as 3 weeks.
First, you’ll experience the initial phase: carb withdrawal. This, which is sometimes referred to as the keto flu, can last anywhere from 3–14 days. It’s when your body works through its carb reserves and screams for you to replace them.
From there you’ll shift into the second phase, which can last between 6-8 weeks. Here your body really starts to make the transition from burning glucose to fat.
Once you’ve maintained this stage for several weeks, you’ll be in maintenance mode. That means your fat burning coasts on autopilot as long as you continue to fuel your body with healthy fats over carbs.
How will you know when you’ve made the final transformation from traditional sugar burner to fat burner?
Let’s go over a few telltale signs you’ve officially made it.
When you’re deep in the low-carb trenches, you’ll want to keep an eye out for a few signs that you are fat adapted.
Your answers to the following questions will let you know if you’re still burning sugar or if you’ve finally switched to fat:
- Are you able to go longer without eating between meals? So instead of only making it 2-3 hours, you’ve switched to roughly 4-6 hour increments instead.
- Are you experiencing consistent energy throughout the day? Remember those energy slumps I mentioned earlier? If you’re fat adapted, you shouldn’t be experiencing these nearly as much (if at all) because your fat stores will meet your body’s energy needs.
- Are you able to work out without having to fuel yourself with a ton of carbs? Once you’re fat adapted, you’ll have all the fuel you need for intense exercise and physical activity. If you’re an endurance athlete still relying on carbs as your prime workout fuel, you’re not fat adapted yet.
Answering yes to these questions means there’s a high chance you’re fat adapted and burning fat as your primary fuel source. Congratulations!
If you’re not fat adapted yet despite following a low carb diet your carb intake may be too high for your body. Or your protein and fat levels may be too low.
Up your fats and proteins a bit to help you lower your carb intake further and you’ll reach a fat adapted state soon enough.
Some people believe using keto strips can help you determine your state of fat adaptation. Unfortunately, these don’t give you an accurate answer.
So does that mean being fat adapted and being in ketosis are the same thing? Or are they totally different?
I’ll clear up this common misconception next.
So far I’ve mentioned that to get to fat adaption, you need to reduce your carbs and increase fats and proteins.
You may be thinking, Isn’t that the same as a ketogenic diet? Shouldn’t I just aim for ketosis instead?
Short answer: being fat adapted and being in ketosis are two different states.
Fat adaptation means you’re using fat as fuel through fat oxidation and glycolysis, or using glucose as energy.
A ketogenic diet — which means eating a mostly fat-based diet comprised of animal fats and high-quality protein — puts your body in a state of ketosis.
Ketosis means your body produces ketone bodies for energy in an attempt to use fatty acids.
You can be in ketosis without being fat adapted. This generally happens as you make your transition from a carb heavy diet to one fueled by fats and protein.
Consider being keto-adapted like an in-between stage where you’re not yet seeing the fat-burning perks of fat adaptation, but you’re well on your way if you keep your stick on the ice.
You can be fat adapted without being in ketosis. You don’t have to follow a keto diet to become fat adapted. Some people end up in a maintenance mode where they consume an amount of carbs that’s not as low as a keto diet, but pretty close to it.
That means you can eat a vegan diet, paleo, or even try intermittent fasting and not eat much at all during a fasted state. This leads to fat adaptation but not necessarily ketosis.
So which one do you want?
Fat adapted or ketosis?
Is there such a thing as a fat adapted keto diet? Let’s sort out the confusion next.
Should You Reach a Fat Adapted or Ketosis State?
Don’t let all the terms we discussed today confuse you. When you’re just starting out, aim for ketosis.
This is when your body starts switching from being a sugar burner to fat burner.
To get to this point, cut down your carbs to around 20–25g per day, increase your fats and watch your protein intake.
This also happens to be the same formula for getting to a fat adapted state.
So as long as you keep to a low carbohydrate diet within the 20-25g range, being in ketosis will help you turn into a fat adapted machine.
But, you may also find, as many do, that you’re likely to prefer ketosis to being fat adapted.
The positive benefits of being in ketosis include:
- Improved metabolism
- Migraine relief
- Weight loss
- Reduced inflammation
- Improved mental health and better moods
Now if you’re only after fat loss and you don’t care about the other health benefits I just dropped at your feet, a fat adapted state may work better for you.
But unless you’re training for a competition, you’re almost always better off focusing on your health instead of just weight loss.
To learn more about a ketogenic diet, which gives you fat burning benefits plus other important health perks, check out this guide.
Devan’s obsession with health and fitness started early and there’s been no stoppin’ her. When she’s not writing for PK, you’ll find her curled up with one of the many health books she’s devouring or outside looking for her next adventure.