Test Breath Ketones without a Ketonix (using a cheap breathalyzer)

[Ijjunne]

I’ve heard the ketonix reading is dependent on the way you breath into it. Maybe you’re not consistent.

[Jimbo]

Yes, I’m still working on my technique. The breathalyzer seems to be much more forgiving of differences, but a small difference in technique makes a big difference on the ketonix.

[brownfat]

The ketonix scales the result of the detector chip such that at low levels of ketones the range is expanded but at high levels the range becomes compressed. I’m mostly in the range of 0.02% to 0.05% BAC on my breathalyzer but I’m currently fasting and have been getting readings from 0.10% up to 0.19% which I think is the max reading it goes up to.

[Jimbo]

73 hours into my fast.

blood ketones: 0.8 mmol/l
breathalyzer: 0.02 %bac
ketonix: 8 ppm

[KBDelight]

This thread… Is long! Lol

So I’m nearing the end of my study. Should have a full range of results in August and blood results after that sometime. It’s a study so they try to bulk process to save costs and the numbers are the same for them.

So anyways, near the end of the study which also means near the end of free glucose and ketones test strips! Bummer! (Going to try and see if they have any other studies or if I can be a Guinea Pig for something so I can keep getting them but funding is funding). The idea of joy pricing my finger sounds great and being able to test more frequently… But nothing seems even close to consistently accurate on the regular other than blood. A little frustrating.

[roxanne]

Hah…someone is actually marketing what looks like cheap breathalyzer as a"keto detector"

https://ketodetector.com/products/keto-meter-ketogenic-diet-detector

[brownfat]

Yes, it looks like they are merely reselling the Greenwon for 10 times the price. If you look closely at the picture you can see it still displays BAC which is blood alcohol content.

Also, if it is selling out fast why do they offer a quantity discount? Evil scammers.

[roxanne]

Yah, I saw the BAC, want sure if it was a Greenwon. They do have some suggested correlations with blood ketones but not sure if I’d trust them at all.

[Jimbo]

84 hours fasted.

blood ketones: 2.0 mmol/l My highest ever
breathalyzer: .04% bac
ketonix: 5.8 ppm

[devhammer]

Hmm…not seeing strong correlations between the three, at least not from the data points you’ve posted.

[Jimbo]

Yes, that was what I was thinking.

I guess it makes sense since the urine strips, the blood strips and the breath analyzers are measuring 3 different (related) chemicals.

From the Ketonix manual:

[quote] Comparison to Blood Testing
A common misunderstanding is that breath acetone directly correlates to the blood
test ketone beta-hydroxybutyrate. It is easy to make that assumption, and in some
contexts it appears to correlate.
When fatty acids break down in the liver to acetoacetate. Acetone is spontaneously
released from the AcetoAcetate. Excess AcetoAcetate is stored in blood as betahydroxybutyrate.
Acetone is a waste product that is not stored in your body.
Beta-hydroxybutyrate is buffered energy which can be converted back to
AcetoAcetate which then is used to create energy (ATP).
The concentration of Beta-hydroxybutyrate is a product of how much excess
AcetoAcetate that is not used and time.
The concentration of Acetone in breath indicates the amount of AcetoAcetate
produced by breaking down fatty acids in the liver (ketosis).[/quote]

This article says there is a relationship, but so far I’m not seeing it. I bought 100 blood ketone test strips, so I’ll keep doing this for a while.

http://onlinelibrary.wiley.com/doi/10.1002/oby.21242/full

From the article:

http://onlinelibrary.wiley.com/store/10.1002/oby.21242/asset/image_n/oby21242-fig-0002.png?v=1&t=j5h8sh47&s=fb22529e27148b415869eccd51b679f7c739b763

Breath acetone concentration (BrAce) has a non-linear relationship with blood β-hydroxybutyrate. Experimental data (open circles) were captured from multiple studies [5, 17, 21-23] and fit (black line) using an exponential relationship [21]. 1 ppm = 39.7 nM (molar basis).

[Jimbo]

Broke my fast about an hour ago at 94 hours.

blood ketones: 1.0 mmol/l
breathalyzer: .03% bac
ketonix: 11.1 PPM

[roxanna]

Is that for all breathalyzers? Mine always shows between .18 and .28 but not sure what that actually means!

[roxanna]

Actually I figured it out - looks like this means .018 and .028.

[Jimbo]

I think I have my ketonix technique nailed down, so hopefully I will get more consistent readings.

First day post fast. Haven’t eaten in 12 hours. Not hungry.

blood ketones: 0.5 mmol/l
breathalyzer: 0.02% bac
ketonix: 9.6 ppm

[Paolo_Di_Donato]

It looks like there is a relationship between the ketonix and cheap breathalyzer. Interesting to see.
I bought the 5 breathalyzers when they were on for $2 (thanks for the tip), I will be comparing if they all give the same readings at the same time of testing or if there could be inaccuracy from device to device.

[Duncan_K]

Meh, got a Greenwon yesterday and out of the box it looked promising, I’d just finished a fast and it registered 0.5. Today I decided to measure it against blood ketones.

It just seems to measure 0.1 now regardless of how I blow into it. Ah well.

[Jimbo]

It makes sense. They are both measuring acetone in the breath, although that isn’t the intended use of the breathalyzers. Alcohol and acetone molecules are similar enough that it detects them both. The ketonix seems more precise. Perhaps because it was designed specifically to detect acetone, although it too detects alcohol. Or perhaps it is just that the PPM measure is more finely granular than the % bac scale.

It will be interesting to see the results of your test. The hardest part will be ensuring that you are breathing the same way every time.

[roxanne]

Interesting study, I found this particularly interesting:

“For rebreathing, subjects breathe ∼1,000 ml into and out of a sealed bag over six breath cycles [9, 77, 78]. This maneuver typically lasts from 30 to 50 s and, for some subjects, can become uncomfortable because carbon dioxide buildup build-up throughout the maneuver increases respiratory drive. With rebreathing, air is in close contact with blood for up to 10 times longer than with other breathing maneuvers. Thus, acetone exchange is more complete which minimizes the effects of human factors and causes BrAce to more closely resemble blood acetone. Although rebreathing may be difficult for some subjects, it provides the best accuracy and repeatability of the three maneuvers.”

I tried both breath holding and rebreathing, and both increase the BAC% reading to the point where I set off the alarms

[Jimbo]

The technique I’ve settled on for the ketonix is breathe normally, then pick a breath, breathe out about half the breath then hold for 5 seconds. Then breathe the rest of the breath into the ketonix. I’m getting much more consistent numbers. Time will tell how well the breath numbers correlate for me. I also suspect the correlation might be different for others. Or perhaps there is a more complex relationship. For example, blood ketones high, breath acetone low. Then the next day the reverse as the ketones in the blood are metabolyzed and become acetone in the breath.