What’s the difference, and why does it matter?
First, let’s define our terms. You may have heard/seen these terms used interchangeably, but while they are similar, they are not exactly the same:
Ketosis = metabolic state characterized by raised levels of ketone bodies in body tissues.
Fat adaptation = metabolic state of being able to effectively utilize and burn fatty acids.
Keto-adaptation = physiological process whereby your cells have adapted to using ketones and fatty acids for fuel.
The simple difference between being in ketosis and being fat- or keto- adapted is the ability of your body to utilize fat for fuel.
The simple difference between being fat-adapted and keto-adapted is the ability of your body to burn fatty acids for fuel vs. being able to burn BOTH fatty acids AND ketones for fuel.
So, which of these is the most beneficial? Which should we be striving for on our quest for optimal health and body composition?
Let’s look at the benefits of each…
KETOSIS
Think of the state of nutritional ketosis as the means to an end, not the end in of itself.
The benefits that you’ve heard of from being in ketosis, are not likely to be felt until your body is effectively utilizing the ketones it’s producing.
Being in a state of nutritional ketosis may not feel so good before you’ve become keto-adapted.
Most people enter a state of ketosis from time to time, if they haven’t eaten for a while, or have intentionally or unintentionally deprived their body of carbohydrates. But, if they are not keto-adapted, the body sees this as a state of emergency. It will produce ketones as an alternative, back up source of fuel UNTIL IT GETS CARBS AGAIN.
This is why many people struggle with maintaining a ketogenic lifestyle when they “cheat” or have “carb-ups” before they get adapted. They end up battling low energy, brain fog, headaches, and other forms of keto flu over and over again, as they go in and out of ketosis – sending their bodies on a blood-sugar rollercoaster.
This is what happens when you are in ketosis but not keto-adapted. Your body is producing ketones, but it has not yet ramped up the enzymes and mitochondrial machinery required to properly and effectively utilize those ketones for fuel. It’s still wanting to use glucose.
When you’re in ketosis, but not yet keto-adapted you’re in what I like to call “energy purgatory”.
FAT-ADAPTATION
People often attribute the weight loss, stable energy, and performance enhancements of a high-fat diet to ketones. But many of these benefits are due to fat-adaptation. These benefits include:
- Fat loss (vs. water weight loss)
- Craving control
- Need less food (lowered hunger)
- Steady energy
- Mental performance
- Endurance capacity
But the main benefit of fat-adaptation is that once you’re fat-adapted, you can handle a carb-load and rapidly return to burning fat once blood sugar and insulin levels subside.
Becoming fat-adapted does NOT require you to be in nutritional ketosis, it simply means that you can tap into stores of fat, break down the fat, and use it as a source of energy.
We all have the capacity to do this. The more readily/easily you are able to switch between using either of the two fuel sources, carbohydrate and fat, is termed ‘metabolically flexible’.
Fat-adapted just means you can easily access fat (either dietary fat or body fat) for energy. It doesn’t mean that glucose can’t or won’t get burned. So, having carbs now and then—provided it’s not excessive—is no problem for fat-adapted individuals.
Consider a fat-adapted athlete enjoying a dinner of steak and two large-sweet potatoes. The carbs will surely kick her out of ketosis, but by morning, she’ll be burning fat again.
Essentially, being fat-adapted = more resilience.
KETO-ADAPTATION
Whereas fat-adaptation can occur to varying degrees dependent on the degree of carb restriction, keto-adaptation represents a more comprehensive reshaping of many physiological systems.
Keto-adaptation only happens when carbs are restricted to a point that induces sustained nutritional ketosis. The nuances here are subtle, but meaningful.
For example, moderately restricting carbs may induce some degree of fat-adaptation and perceived benefits, but falls short of maximizing fat oxidation and producing the positive health outcomes specifically linked to nutritional ketosis.
A keto-adapted person is by definition fully fat-adapted, but a fat-adapted person may not be keto-adapted.
The benefits you may gain from being keto-adapted or how keto-adapted you are, will vary according to the duration that you are on the ketogenic diet. For instance, studies show that athletes who have been on the ketogenic diet > 6 months have adapted to be able to recover their muscle glycogen (carb stores) levels at the same rate as athletes on a high carb diet. However, this isn’t the case for athletes who go on the ketogenic diet for 4 weeks.
Also, by being keto-adapted, you get the benefits of being fat-adapted with the additional benefits of ketone bodies.
So ultimately, ketosis is NOT the GOAL. It is simply the means to the end. Keto-adaptation is the END GOAL.
HOW LONG TO KETO-ADAPT?
So, what does it take to go from being in ketosis to becoming keto-adapted and how long does it take?
Depending on you and your genes, as well as other factors, such as long-term diet, how sensitive you are to insulin, training and health status, will determine both the extent to which you become keto-adapted and how quickly this process takes place.
Simply put – patience grasshopper!
Unfortunately, there is no way to rush this process. And for newbies, the more often they stray from keto, the more difficult it will be for their body to become keto-adapted.
The best way to get fully keto-adapted is to commit to following the plan 100% (no cheats!) for months – not days or weeks – and TRUST THE PROCESS.
Consider your current status and objectives:
- What your goals?
- Are you currently fat-adapted?
- Are you looking to lose fat?
- Are you looking to improve overall health?
Here’s a simple way of gauging your level of fat- or keto-adaptation:
- Can you comfortably go several hours without eating and feel no hypoglycemic effects?
- Do you have good, steady physical energy levels?
- Is your mind sharp and thinking clear?
- Do you feel hungry, rather than hangry?
- Do you crave protein and fat-rich meals, rather than sweets or starch?
Reflecting on the questions above, where do you believe you are in the process of adaptation, and what’s your goal – do you want to be “in ketosis”, “fat-adapted”, or “keto-adapted”?
REFERENCES:
http://www.tuitnutrition.com/2016/01/dont-be-a-ketard1.html
http://www.tuitnutrition.com/2016/01/dont-be-a-ketard2.html
http://www.tuitnutrition.com/2016/02/dont-be-a-ketard3.html
http://www.tuitnutrition.com/2017/09/measuring-ketones.html
https://drinklmnt.com/blogs/health/4-ways-to-become-fat-adapted-and-why-its-different-than-ketosis
https://www.fitforfilms.com/educate/antonia-osbourne/keto-adapted-versus-fat-adapted
https://www.virtahealth.com/faq/fat-adapted
https://www.virtahealth.com/blog/keto-adapted