With the rise in interest in the n=1 experiment I’ve been blogging about since May 2012 (read my latest updates about it here, here, here and here), so many of you have begun testing your own blood ketones to see how well you are doing in pursuit of reaching that glorious state of “nutritional ketosis.” Attaining blood ketone levels of 0.5-3.0 millimolar is the optimal level for producing an appropriate level of beta-hydroxybutyrate to commence fat-burning and to serve as an excellent alternative fuel source for your brain and body for optimal performance according to what Dr. Stephen Phinney and Dr. Jeff Volek outline so beautifully in their outstanding MUST-HAVE 2012 book The Art & Science Of Low Carbohydrate Performance. If you haven’t already picked up your own copy of this book, then I cannot recommend it highly enough to you as an invaluable resource in your pursuit of living an optimally healthy low-carb lifestyle.
As people have been shopping around for their own blood ketone meter, I’ve been getting a lot of e-mails from readers who have asked me for my recommendation between which of the two major ketone meters they should get to test their blood levels. Is there any difference between the Precision Xtra and NovaMax Plus blood ketone meters? I’ve personally tried both of these meters and have been using the Precision Xtra results to document my n=1 experiment.
Let’s take a closer look at the PROS and CONS of each:
- Accurate and clear blood ketone measuring
- Sturdy and strong test strips
- More precise than urine ketone testing
- Requires more blood than glucose testing
- Test strips can be quite expensive
- Not available for purchase in stores
- Test strips are very thin and flimsy
- Lower readings are not detectable
- Not available for purchase in stores
One other issue to keep in mind when deciding which meter to get was brought to my attention by a researcher who is using both of these ketone meters with people simultaneously to see how close the two readings are. Knowing your blood ketone level is an essential part of getting into nutritional ketosis, so accuracy is the key. According to this researcher, the NovaMax Plus was “frustrating” because it gave a generic “LO” reading quite often requiring retesting which he says “gets expensive” quickly. He’s currently talking with the manufacturer about these issues.
At the same time, he notes that the Precision Xtra is “far superior” for both accuracy and displaying the proper levels of blood ketones. In all the testing he’s done as part of his research, the results from this meter “best matches our assays” which he says is “the most effective method.” He wanted to make sure my readers who might decide to test their blood ketones were aware of these issues he has found. Here are some photos of the discrepancies he found between the Precision Xtra (on the left) and NovaMax Plus (on the right) ketone meters:
Interesting, eh? It’s curious that even at 0.6 on the Precision Xtra, the NovaMax Plus showed “LO” although this would be considered on the lower end of nutritional ketosis. This doesn’t help you if you’re trying to GET into nutritional ketosis and may even discourage your efforts to do this in earnest. We don’t want that to happen. With this information about the two blood ketone meters, I wondered if the same discrepancies would show up for me since I tend to show higher ketone levels. Here were the results of my two separate tests of the same blood sample measured at the same time:
While they’re still not the same, the difference isn’t quite as stark as with the lower levels of blood ketones. Still, it’s good to know what you’re getting yourself into if you decide to go with the NovaMax Plus over the Precision Xtra ketone meter. My personal preference has been the Precision Xtra despite the extra costs involved. Knowing my ketone levels down to the precise tenth of a millimolar is scientifically important for my n=1 testing and the accuracy of my nutritional ketosis experiment. I’m testing daily, but others of you are testing once or twice a week. So knowing your precise levels of blood ketones is critical. I can imagine seeing a “LO” reading on the NovaMax Plus which many of you have reported seeing makes you want to pull your hair out. I hope this helps you make an informed decision if you decide to conduct your own test of this concept for yourself.