Measuring Your Ketones

Those colored strips don’t tell the whole story.

Article by Rekka Jay | 24 Jan, 2021

Article originally published on on 5/9/17. It has been lightly edited for re-publication.

So, you have your brand-new ketone strips. Congratulations!

I'm sure you would rather have had a nice cup of coffee with heavy whipping cream, Kerrygold butter, or some nice vanilla extract for flavor. Now, hopefully you're reading this before you actually make the purchase, but chances are like many new ketonians, you did not read this blog post before going out and buying these ketone strips that you've heard so much about. The fact is, for our purposes those ketone strips are basically useless.

Yes, you can measure your ketones with ketone strips. But what exactly are you measuring?

What Is It?

Ketone bodies come in three primary forms:

  • Acetone – acetone occurs when your body converts ketones for energy and the excess comes out in your breath. Yes, the same stuff used to remove nail polish! This can sometimes result in an unusual odor to the breath, which some people call "ketone breath" or even "dragon breath."
  • Beta-hydroxybutyrate – this is the ketone body that exists in your bloodstream and is used by your body when it wants to access ketones for energy.
  • Acetoacetate – this is what is wasted by your body when it doesn't use ketones that your body produces. This is what ketone urine strips measure.

OK, So How Do I Measure Them?

Because there are three main different ketone bodies, there are three different ways to measure them. Without understanding each ketone body, you may look at the options, see the price difference for the measurement tools, and base your decision on which one you can afford. That's fine, you can do that. However, you need to know what exactly it is you're measuring.

If you measure using ketone urine strips, you are measuring acetoacetate–the ketones that did not get used by your body. In other words, these are the ketone bodies that your body flushed either because it didn't know how to use them, or because you had more than it knew how to use.

 When you measure ketone bodies at the beginning of your ketogenic lifestyle, you may be very pleased to see that you enter the purple range. Again, these are wasted ketones. If you are eating keto and not taking exaggerated ketones, there's no reason to worry.

A similar, external factor that can spike your ketone strip reading, are exogenous ketones. When your ketone strips read purple after you take an expensive dose of exogenous ketone, you can be sure that you have just flushed that dose of the expensive product down the toilet. Congratulations.

There is also a lot of confusion caused by the way these urine test strip results change over time. When you start off on a ketogenic way of living, you will produce ketones starting at the 24-hour mark, but your body will not be adapted to using them. At first, your results will likely fall on the deep purple end of the range, and you will be tempted to proudly post photos of your pee-soaked strip to the Ketogenic Success group (this is not necessary, thanks anyway!).

Eventually, your body will start to use these ketones to better effect, and then you may find that your ketone readings on ketone strips reduce drastically compared to what you saw in the first few days. Still, many new ketonians freak out when this happens, worried that they are no longer in ketosis. The fact is, that they are likely more fat adapted, and the body is using their ketones without wasting nearly as many as it once did. Some people who are fat adapted even find that they eventually get a negative reading on their ketone strips. When following a well-formed ketogenic diet, this will happen long before you run out of your first pack of urine strips. This confusion and eventual uselessness of the method is why we do not recommend purchasing ketone strips for people who do not need to monitor their ketones closely, such as a Type I Diabetic.

Using a blood meter, you can measure beta-hydroxybutyrate which is the form of ketone body that exists in the bloodstream, ready for use by the body whenever it might require it. Beta-hydroxybutyrate strips are expensive, sometimes difficult to even find in the first place. Again, they are not measuring how your body uses the ketones it produces. What they measure is the available supply. Pair this information with results from ketone urine strips and you do start to get the bigger picture of your body's ketone production and usage, but it's not the whole picture.

Measuring acetone in your breath with a breath analyzer, such as the Ketonix, you will get a reading which should, in ideal conditions, tell you how much ketone supply you are actually burning. Remember, acetone is the used ketone body, so whatever you breathe out is what was effectively put to use. The disadvantage is that you need to breathe into the analyzer consistently and for the appropriate length of time to record a reading. There is some question as to how accurately you can blow into a breath analyzer every single time. Luckily, the Ketonix takes multiple readings with no need for disposable test strips, so you can test multiple times in each session to see if you get a consistent reading.

Which One Should I Choose?

As you can imagine, the ideal situation would be to measure your ketone bodies using all three methods, all at the same time, each day that you test. However, that is neither affordable nor necessarily feasible for most people. Our suggestion would be to pick one method, understand exactly what it is you are measuring and the drawbacks to the method you use, so you don't misinterpret the result. If you measure consistently at a certain time of day, and at a certain distance in time from your last meal, you will at least start to understand how the food you eat affects your ketone production, usage, or waste.

Any method of measuring ketone can be effective for a user who understands what it is they are measuring and understands how factors in their ketogenic lifestyle may change the result. You must pair the readings you record with a holistic look at your behavior and environmental factors.

Remember, whichever method(s) you decide to use, testing is only a place to begin understanding how your body functions on a ketogenic lifestyle, not the ultimate measurement of success or failure.

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