A few months ago, I received my first keto breathalyzer and would like to share my thoughts on this device. The creator of the Ketonix breathalyzer, Michel Lundell, also runs a website to help and support people who use the device for measuring their ketone levels. The price of Ketonix is $ 149 (or $ 169 with the battery).
You can buy the Ketonix breathalyzer at Ketonix.com. I was given this device free of charge and I'm not affiliated with Ketonix. The opinions expressed and photos in this post are my own.
Measuring Ketones in a Nutshell
Before I get to details of how to use the Ketonix breathalyzer, I'd like to start with some basic facts. There are 4 ways to measure your ketone levels:
Ketostix. It measures urinary ketones (acetoacetate), is inexpensive but inaccurate because it only measures "wasted" ketones in your urine. In fact, once you get keto-adapted, you may not be able to measure any.
Blood Ketone Meter. It measures beta-bydroxybutryate (BHB) and is the most accurate method of measuring ketones (although BHB is not technically a ketone). The drawback is that the strips are fairly expensive, especially if you measure frequently.
Observation and following a healthy ketogenic diet. In my opinion, if you don't follow a keto diet for therapeutic purposes (or for performance enhancement), you don't need to measure your ketone levels. In fact, you don't need to follow a very low-carb diet to lose weight. What matters is finding your personal carb intake and also consider other factors that I explained here.
Breathalyzer (Ketonix). It measures acetone (acetone is made from a break down of acetoacetate). It's great value for money as it's a one-off payment, there is no need to buy expensive strips and it's accurate enough to tell you whether or not you are in nutritional ketosis and give you an approximate measure of how your ketone levels fluctuate. It will also give you idea of how certain foods affect your ketone levels.
Keep in mind that ketone levels will not tell you how much fat you've been burning. Don't worry if you never measure high ketone levels with any of the above methods. There is no evidence that more ketones will help you lose more weight. High ketone levels have therapeutic uses in epilepsy, Alzheimer's and cancer, or may benefit athletes.
In my review, I'm not going to focus on the correlation of blood ketones and breath ketones (here is a review focused on that). Instead, I focus on how to use this device. The reason I decided to do that is that I found the user interface quite challenging. The good news is that the people behind the device are planning to add several new features, including a wizard that will guide you through the process of measuring your ketones.
How to Use the Ketonix Breathalyzer
1. Create an Account at Ketonix and Download the Software
First, you'll need to create an account at Ketonix.com. Once you create an account, you can download the Ketonix software for Mac or Windows in My Menu -> Downloads.
2. Setup the Ketonix Software
The first time you use the device, it may take up to 30 minutes to get it ready for measuring. Connect your Ketonix into your computer via the USB port. Once you plug the Ketonix into your computer, it will start Initializing (see step 4 for more information on what it means).
3. Create a Profile
All measurements you take will be recorded against a user profile. To create a profile, go to File -> Profile -> click on the "+" button on the bottom left. Enter your Profile Name and choose where you want your data saved on your computer by clicking on the browse button. Enter the File Name and add the .csv extension (I named mine "MartinaKetonix.csv").
Enter the Username and Password for the account you created at Ketonix.com). Optionally, select Gender, Age and Usage. Click on Create Profile and click on Verify. Verify will link your local account to your Ketonix account. You can only verify once you have entered the correct username and password. Then click Close.
Initializing is the process of preparing the device for measuring. For day-to-day readings, you have to wait until the device is initialized before you take any readings. If you are setting up the device for the first time and going through steps 1-3 your device should be initialized by now. In any case you have to make sure you have to wait until intitialization is complete - the light on your Ketonix will stop flashing.
What does initializing do? The sensor needs power to heat up every time you plug it in your computer.
Before you start using your Ketonix, you have to calibrate it. To do that, go to File -> Calibration and click Start. Wait until the calibration is finished. It will take several minutes so be patient.
Why calibrate? The calibration sets a reference value making readings consistent. Each environment (temperature, pressure) is different. Also, using the device over time will affects readings. You only need to do this once unless you change environment or haven't used your breathalyzer for a long time. The value displayed should be close to zero once the calibration is done.
6. You are Ready to Measure
Make sure you select the right Profile before you measure (Select Profile -> your profile) and that the initializing process has finished.
On the side of the mouthpiece, you'll notice there is a small hole. There is a corresponding one on the device and they have to line up precisely. If they are not aligned, you won't be able to exhale into the breathalyzer and take a measurement.
To take a measurement, first click Start and then start blowing into the breathalyzer. To do that, breathe as normal (do not take a deep breath). Blow for about 15 seconds or as long as it feels comfortable.
7. Save the Results
Remove the breathalyzer from your mouth and wait for the readings to settle. This may take up to 30 seconds (mine take no longer than 10 seconds). After measuring, keep the Ketonix plugged in for another minute to eliminate moisture in the sensor. Then, keep in in a box to avoid dust getting in the sensor. If you want to take another measurement, wait until the blue light is not flashing.
As soon as you see the "Time to click on Stop & Save?" message, click Stop & Save. The results will be saved on your computer on the location you specified when you created your profile.
8. Preview Your Results
While taking a measurement, the Ketonix will also indicate your ketone levels using different colours on the device (blue for no or very little ketones, green for small amounts, yellow for moderate and red for high). The new Ketonix model also indicates the level by flashing (1 flash means the lowest concentration and 10 flashes represent the highest value).
Your results will also appear online at Ketonix.com (My Menu -> Ketonix Charts) - just click on the chart to see a larger version. You can also access the online results directly from your computer (View -> Charts). I've been told that there will be offline (local) charts in the next release.
Using a Battery
If you are travelling, you can use the optional battery. This allows you to quickly check your average ketone levels. The drawback is that you won't be able to save your measurement.
Always make sure you charge the battery, ideally overnight, before using with the breathalyzer. The blue light will be flashing while the device is initializing. Wait until the light stops flashing and then blow into the breathalyzer (again for about 15 seconds). After you finish blowing, give it a few seconds. In the new model I tested, the blue light will change and it will start flashing (1-10 times). The consecutive quick flashes are the ones you want to count although you don't have to as the colour itself will give you an indication of your ketone level: blue (none), green (low), yellow (moderate) or red (high) light.
How to Get Best Results
Keep the measuring consistent. Ketone levels are typically low in the morning and increase during the day with the highest levels before bed. It doesn't matter when you measure but the rule is that you should measure at the same time of a day to get the most consistent data. During my experiment, I measured twice a day (noon and evening) - thus the fluctuations.
Food intake. When and what you eat will also affect your ketone readings. Keep that in mind and don't be surprised when you see fluctuations.
Alcohol consumption. Do not drink alcohol before measuring. Since the Ketonix measures acetone, you won't get accurate readings and your values will appear artificially high.
Try to exhale for the same period of time. The longer you exhale, the higher the ketone readings may appear. It's good to stick with the same time - like 15 seconds every time you measure.
Which Model to Choose
There are two types of the Ketonix breathalyzer - the old and the new model. The main difference is that the new version provides more accurate data when not using a computer. The new model indicates 1-10 flashes for each level - blue, green, yellow and red. It costs $ 149 without the battery and $ 169 with the battery - the old model is $ 75. To see which ones they are, go to Ketonix.com
The new models (both Red and Blue) are pre-configured to different ranges. The Blue defaults to the "Standard" range while the Red defaults to the "Sport" range. You can always reconfigure these ranges on your computer - see below.
Setting Your Custom Levels
Finally, apart from using default levels for ketone readings, you can change them in Settings. By dragging the knobs for green, yellow and red, you can easily set ranges. I didn't change these values and kept the device at the default levels.
According to Ketonix, anything between 40-70 is regarded as nutritional ketosis but this may vary for individuals. The official website advices to use a one-day water fast to find your minimum and a 3-day water fast to find your maximum. I'm not convinced this is something you need to do so I just used the default values. If you decide to do that, make sure you consult this with your doctor. Pregnant women and people with health conditions like diabetes, hypoglycaemia and those with eating disorder history should avoid fasting.
How about you? Do you monitor your ketone levels? Which method have you been using and what is your experience?