The ketogenic diet (“keto diet”) has gained in popularity in recent years as a weight-loss tool and a way of increasing metabolic health because it forces your body to burn fat for fuel instead of glucose. Ketone breath analyzers are a way of measuring whether you are in ketosis and are burning fat as a fuel source, and they could make the diet easier to adhere to and more accessible for many people.
What is the ketogenic diet?
The keto diet wasn’t originally designed as a way to help people to lose weight. In fact, its original goal was to reduce the frequency and severity of seizures in children.
The bare bones of the keto diet involve a very low intake of carbohydrates coupled with a high intake of fats and proteins. Doing so puts your body into a state known as ketosis.
Ketosis is when your body has run out of glucose to use as fuel instead of using fat as a fuel source. It is so-called because the liver releases ketones as fuel when the fat is burned.
The ketogenic diet does lead to rapid weight loss, although many scientists caution that it may not be sustainable or safe as a long-term diet.
For people who are following the ketogenic diet, trying to get into ketosis, and staying in ketosis. And it is impossible to know by how you feel whether you are in ketosis or not. And there are multiple options available to find for ketone testing.
Who else might need to do ketone testing?
It isn’t just keto dieters who need to be concerned about their blood ketone levels. People with diabetes, especially those with Type 1 diabetes, should be concerned about their ketone levels.
Insulin is used to convert glucose into energy, and for people with Type 1 diabetes, the pancreas either makes no insulin or not enough insulin. This is why people with diabetes need to take insulin every day.
If there isn’t enough insulin, then your body will not be able to convert sugar into energy and will instead start burning fat as fuel by converting it into ketones.
If too many ketones build up in the blood, they can turn acidic. This can lead to diabetic ketoacidosis, which can be life-threatening.
How to test for ketosis
Ketosis can be detected through testing blood ketone levels or through the use of urine strips. Blood tests directly measure ketone in the blood and can be conducted at home using a blood ketone meter.
On the other hand, a urine strip measures excess acetoacetate (AcAc) in your urine and is often considered the least accurate method of ketone testing. This is because your body can adjust to keto over time, so it will no longer make excess AcAc.
Both of these methods test the ketone level your body currently has so you can determine whether or not you are in ketosis.
But both blood tests and urine strips are time-consuming and invasive, however. And they can make it challenging to test your ketone level more than once a day. Recent technological developments have found a new way of testing for ketosis: through the use of a ketone breath analyzer.
What is a ketone breath analyzer, and how does it work?
What are they?
The idea behind the ketone breath analyzer, or ketone meter, is similar to a breathalyzer that measures for ethanol when you have a traffic stop. They work on the principle that human breath contains various volatile organic compounds (VOCs) that can be measured by taking samples of the breath.
With ethanol, the amount of alcohol in your blood is directly related to the amount of ethanol in your breath.
A ketone breath meter works in a very similar way. Most ketone meters test for acetone, which is one of the main ketones.
When you are in a state of ketosis, your breath will contain more acetone than it would if you weren’t in ketosis. These breath ketones are what causes the notorious keto bad breath!
Generally speaking, a breath acetone (BrAce) level of 2-40 ppm indicates that you are currently in ketosis and are, therefore, burning fat for fuel instead of glucose.
How do they work?
Most keto breath analyzers use a semiconductor with metal oxides as a reaction sensor (SMO). The SMO sensors are accurate in determining acetone level and acetone concentration in exhaled breath.
What are the benefits of using a breath ketone meter?
One of the significant benefits of using a ketone breath meter is that it can allow you to measure your ketone level multiple times a day. This is important because your ketones can vary over the day, so multiple readings are necessary to obtain an accurate ketone level result.
With a blood ketone test and a urine test strip, it can be difficult to test multiple times a day, so the full picture of ketosis may not be obtained.
Whereas a breath test for ketones is more viable for testing multiple times a day. Most ketone breath meters are small enough to fit in your pocket so that you can use the breath ketone meter after meals, exercise, or at other key points in the day.
Cost should also be taken into consideration. With both a blood ketone meter and urine test strips, you are tied into buying the test strips indefinitely. Whereas with breath ketone testing, you only need to buy the device. So for long-term keto dieters, a breath meter can be a more cost-effective choice.
Is a breath ketone meter accurate?
A ketone breath meter works under the assumption that the acetone concentration in the exhaled breath is directly correlated to the ketone bodies in the blood.
We know that a ketone analyzer is accurate as a test for breath acetone level but does the breath acetone level correlate directly with blood ketone levels?
The gold standard for accurate ketone readings is a blood test. Because a breath ketone analyzer is measuring a byproduct rather than the blood directly, there will always be the potential to interfere with the result.
And there are some lifestyle and dietary changes that can alter breath acetone levels directly. These include eating garlic, taking medications such as disulfiram, exercising, and body temperature changes. In addition, people with obesity may also experience changes to their breath acetone.
Most of these result from metabolism changes, but some, such as garlic, can directly interfere with acetone production.
However, these findings aren’t a death knoll for using breath ketones when following the keto diet.
Most breath acetone meters are designed to be used multiple times a day to give you a daily ketone exposure (DKE) score. This score can be plotted on a graph, and any deviations will be smoothed out over the day.
Using a DKE score, you can be fairly sure that you are looking at your level of ketosis by using a breath ketone meter.
Biosense from Readout Health
The only clinically validated breath ketone meter currently on the market is the Biosense from Readout Health. We will be writing up a thorough review of the device in the near future so watch this space! But first, let’s look at how well the clinical trials say it works.
Participants in the Biosense trial used a blood ketone meter and a breath ketone analyzer (Biosense). The trial found a high level of correlation between the blood ketone levels and the breath ketone levels. This is important because a high correlation means that a breath meter can comfortably measure ketosis.
It did, however, find that there was a time delay between a change in ketones in the blood and a change in ketones in the breath. With blood ketenes happening sooner in time than breath.
This time delay is another reason why taking multiple readings over a day is a good idea to get the complete picture of ketosis status.
The Biosense ketone analyzer measures a single reading each time, but it connects with a smartphone app that collates the single readings together to calculate your DKE and give you a Ketone Score. This tells you the length and depth of your nutritional ketosis each day and gives you a numerical score.
Are there any other ketone breath tests available?
While the Biosense is the only clinically validated ketone analyzer on the market right now, other types of ketone breath analyzers are being developed.
The Ketoscan Mini doesn’t use an SMO sensor. Instead, it uses a photoionization detector that has been calibrated for ketosis. While it doesn’t currently have any published results related to its effectiveness in detecting ketosis, it has been clinically validated for detecting acetone related to other conditions such as lipolysis and heart failure.
It has a patent-pending for its uses in measuring ketosis. However, given its efficacy in detecting other conditions, it is likely that it will also prove to be an effective way of detecting ketosis.
What is the future of the ketone breathalyzer?
The technology for ketone breath analyzers is still in its infancy. Therefore, the future directions of this testing are likely to focus on increasing the devices’ sensitivity. In addition, research is ongoing into augmenting the metal used for the semiconductor metal oxide (SMO) sensor to improve its sensitivity, efficiency, and durability.
Nanotechnology is also being researched to allow for greater oxygen absorption and increase the selectivity to acetone.
Another area for future development is moving away from metal oxidization to use light diffraction and absorption instead.
This can be achieved either by using lasers or ultraviolet light, and these devices could be more stable and more accessible to power.
Is a ketone breath analyzer right for me?
A blood meter is still the gold standard for measuring ketones and ketosis levels. If you are concerned about diabetic ketoacidosis, then it is likely that your doctor will recommend sticking with a blood test because it is so crucial that you get accurate results. With that being said, the more research that validates the accuracy of breath monitors for detecting ketosis, the more likely they are in the future to reach the medical world.
If you are attempting a keto diet, then a breath analyzer could be a great way of keeping you on track. It is convenient and easy to measure your ketone levels whenever and wherever you are, and you don’t have to deal with invasive blood pricks or the mess of dealing with urine strips.
And by keeping a close eye on your daily ketone level, you will be able to see what activities impact your ketosis. This can include when and what you eat and when and how you exercise.
Over time, you will start to find it easier to get into and stay in ketosis, and this will help your keto diet impact your weight and health.
The bottom line
There is a range of methods for measuring ketone levels. These typically include testing your blood and urine, but with the newer breath ketone analyzers coming onto the market, you can test your ketone levels in a much less invasive way.
More research needs to be done to determine exactly how accurate they are, although the currently available results are encouraging. And there are also doubts about whether staying on a keto diet long-term is good for your health, although it does appear to be very effective as a short-term weight loss tool. Nevertheless, if the keto diet is the perfect way of reaching your weight loss goals, then there is a good chance that picking up a ketone breath analyzer could help you to get there more quickly.
