How Do I Know if I am in Ketosis?

The phrase “in ketosis” is pretty loosely thrown around amongst keto enthusiasts.  This is in part because of a misinterpretation of what this phrase means and the definitions given in the literature.

Much of the research refers to being in ketosis as having a certain number of blood ketones. The issue is that some of the research suggests this number is 0.5 mmol/L and other research suggests the number is at or above 3.0 mmol/L. 

These recommendations have led many to chase higher ketone levels and freak out if they can’t achieve them. The problem is that interpreting blood ketone is not cut and dry. Just because you are producing ketones does not mean that you are efficiently using them and that is what is important. We are talking about being keto-adapted here.

Being keto-adapted means that you are not only producing ketones but you are also using them. This takes time. This is the reason why you see high ketone levels within a couple days of keto dieting but you still don’t feel the benefits of keto yet. You are producing ketones but the cells in your body are not good at using those ketones yet.

This means that the real question should be how to know if you’re keto-adapted.  While measuring ketone levels does have its benefits, it does not tell us if we are keto-adapted. A better way to tell if you are keto-adapted is by listening to your body. Here are 5 ways to tell if you are in ketosis.

Fat Loss

Keto is the best weight loss diet out there. It is the reason why most people come to keto. While weight loss may happen rapidly initially, most of this weight is related to water loss.  This initial water loss tends to slow down after a few weeks of keto. At some point after this you will start to a consistent decrease in body fat percentage.  When this point comes you are likely pretty keto-adapted.

Increased Energy

Besides weight loss, increased energy is one of the biggest benefits of keto! When you are using fat and ketones for fuel you have improved your metabolic landscape and this leads to more energy. It’s very noticeable.

However, you will not feel this way when you first start keto. In fact, you may feel very fatigued despite having high ketone levels in your blood. If you stick with keto, you will start using those ketones in your blood and this will lead to a noticeable increase in energy. A great sign that you are keto-adapted!

A quick refresher on how ketosis occurs!

A quick refresher on how ketosis occurs!

Reduced Appetite/Cravings

One of the contributing factors to weight loss on keto is reduced appetite and cravings.

Like your energy levels, this doesn’t occur right away. When you first start keto, you may have a lot of hunger and cravings. As you get keto-adapted, these subside.

There are several mechanisms at play here, including more stable blood sugar levels, changes in appetite signaling hormones, and satiety of fullness signals from ketones.  Regardless of the mechanism, if you are keto-adapted, you should experience this!

Improved Focus/Concentration

This is one of my favorite features of keto.  When you are producing ketones and using them effectively, you will notice a drastic improvement in your cognitive function.  This increase in cognitive function can lead to not only greater focus and concentration but also improved feelings of well-being, alertness, and better memory.

Ketones are the preferred fuel source of the brain. When they are available, the brain soaks them up which leads to more energy to the brain and lower inflammation. A recipe for brain health and improved brain function. When you become keto-adapted, you will feel like a fog has been removed from your brain. Now you can think much more clearly.

Improved Exercise Performance

When you are fully keto-adapted, you are able to tap into a much larger energy reserve during exercise. Stored fat can contain over 20,000 calories in even the leanest of people. Your body can only store about 2,000 calories from glycogen.

This greater fuel source that the body can pull from and convert to ketones gives the body way more available energy to call on during exercise. This is why you will see huge improvements in your exercise endurance once keto-adpated.

Your strength may take a dip when you first start keto but overtime it will return and research has even shown it can improve!

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Becoming keto-adapted can take anywhere between 2 and 6 weeks depending on the individual. If you have been keto for longer than this and are not experiencing any of the signs of being keto-adapted, you may need to get back to the basics and make sure you are following keto right.

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Christopher Irvin