Using Technology to Measure for Ketosis [Part 2]

Published by joseph on

Using nutritional ketosis to prevent and treat diseases other than epilepsy and obesity is a relatively new concept. So there are currently no large clinical trials in existence. Even most biochemistry textbooks hardly mention ketosis except in reference to starvation and diabetic ketoacidosis.

– Dr. Zeeshan Arain

Look for many more breath ketone meters and associated technologies to be developed in the coming years. According to the July 25, 2013, issue of the Journal of Breath Research, Japan’s NTT Docomo is developing a breath ketone reader device and app for smartphones.

And a Swedish engineer named Jens Clarholm posted detailed instructions on his blog for making a homemade breath ketone meter he calls Ketosense (he made one for me to use, and its results are remarkably close to the readings I find on my blood ketone monitor). It would not surprise me if we’ll be able to purchase breath ketone meters in stores by 2016! Now that would be cool.

I’ve said it before, but this point bears repeating: it’s important to remember that when your blood sugar level is in the normal range, the presence of high levels of ketones in the urine, blood, or breath is not at all harmful, no matter how much weeping and gnashing of teeth you may hear from health gurus.

Diabetic ketoacidosis, as we’ve already discussed, tends to occur mostly in type 1 diabetics who cannot produce insulin and some type 2 diabetics who are insulin-dependent, and only when blood sugar levels are in excess of 240 mg/dl and blood ketone readings well in excess of 10 millimolar per liter. For everyone else who can make even a little bit of insulin, there is no danger in seeing higher levels of ketones. But since it can be difficult to produce ketones without deliberate effort, being able to test and see where you stand can be reassuring as you pursue ketosis.

Let’s list the pros and cons of each method for measuring ketones.

Urine testing


  • It’s the least expensive method for testing ketone levels.
  • The test is completely painless, since you just pee on a stick.
  • There is a clear color change within fifteen seconds when ketones are present.
  • If you have ketones in the urine, then you are definitely in ketosis.


  • It only measures the ketone body in the urine (acetoacetate).
  • Once you become keto-adapted, ketones in the urine may disappear.
  • Long-term ketosis cannot be measured using this testing method.
  • If you do not have ketones in the urine, you still might be in ketosis.

Everybody likes urine ketone testing because the strips are readily available in stores, cheap, and easy to use, and they produce a color change if you are in a state of ketosis. But this mode of ketone testing is fool’s gold for people who have become fully keto-adapted after a few weeks of low-carb, moderate-protein, high-fat eating and are now burning fat for fuel efficiently.

After a period of transition as you shift from a sugar-burner to a fat-burner, ketones may stop spilling over into the urine, giving you the false test result that you are out of ketosis. What has actually happened is that your ketones are now showing up in the blood and you’re experiencing the long-awaited benefits of nutritional ketosis. Thus, solely relying on urine ketone strips to see if you are in ketosis after successfully making the switch is futile. The bottom line is they are just not a reliable means for tracking your ketone production beyond the initial period of adaptation.

Blood testing


  • It’s the most precise
    measurement for detecting ketones (beta-hydroxybutyrate).
  • There’s no ambiguity about the results with a clear digital
  • It tests for the most prevalent ketone your body is using for


  • The testing strips are more expensive ($2 to $6 per strip).
  • Blood ketone testing supplies are hard to find in stores, so you may have to purchase them over the Internet.
  • The test requires a painful finger prick for a blood sample.

If you’re not used to pricking your finger to test your blood, then blood ketone testing will likely be intimidating at first. But once you get over this mental roadblock and start testing your blood often, there’s a certain confidence and assurance that comes from knowing your blood ketone levels. The blood ketone monitors (especially the Precision Xtra) give an incredibly accurate digital measurement of your level of ketone production.

In the next chapter I’ll share my experience testing blood ketones at least twice daily for an entire year to give you an idea of what to expect. But this is arguably the very best method right now for knowing how well you are doing on your ketogenic diet, and it’s worth every penny it costs to test.

Breath testing


  • It’s an easy testing method that you can do practically anywhere.
  • It’s the only way to measure ketones (acetone) in the breath, which correlate well to the level of beta-hydroxybutyrate in the blood.
  • Unlike blood ketone testing, there’s no painful finger prick.


  • These devices are not yet as commercially available as the other ketone tests.
  • Different meters have different ways of showing results, and currently there’s no standard for correlating breath ketones to blood ketones.
  • Not everyone may be able to or want to blow into a device for the ten to thirty seconds required.
Categories: Health