Are Breath Ketone Meters Accurate?

How accurate are breath ketone meters to monitor fat burning diets or should I go for blood ketone meter?

Read our tips help you decide which is best for you

What is a breath ketone meter

A breath ketone meter looks similar to a hand held alcohol breathalyser, and the technology is in fact very similar. They are used to monitor breath ketone levels, and are a useful tool to monitor fat burning on many popular diets.

How do ketone levels on the breath tell you if you are burning fat

When the body uses fat as a fuel, ketones are produced as a by product, and the levels of the ketones can be monitored either in the urine, on the breath, or in the blood. The presence of the elevated ketone levels, is a sign that fat is being used by the body for energy, commonly known by dieters as fat burning

Ketone levels on the breath are elevated when we burn fat and can be measured with a ketone breath meter 

How accurate is a ketone breath meter at measuring ketone levels?

When compared to a blood ketone meter, a breath ketone meter is far less accurate, and the readings tend to vary considerably. It should be regarded more as a guide to whether or not you are in ketosis. So many factors can affect the readings on a breath ketone meter, and they can give wildly varying readings.

How to get accurate results with a ketone breath meter

• We have found the best way to use a ketone breath meter to get accurate reliable results is to only use it once a day, first thing in the morning as soon as you get out of bed, before you have a drink or even brush your teeth. Ideally, keep it next to the bed, and do it before you even get out of bed.
• If used in this way the ketone breath meter will give very accurate results ( unless alcohol has been consumed the night before ).
• If you want to test more frequently than this you are best going for a blood ketone meter as this will give more accurate results at all times of the day. If you want to test your ketone levels more frequently but do not want to have to do finger prick blood testing, then a combination approach where you use the breath ketone meter first thing in the morning and then test your urine for ketones with urine ketone test strips later in the day may work well.

What causes a breath ketone meter to give inaccurate results

• Any alcohol (even tiny amounts) on your breath when you blow into the ketone meter will give very high readings, and may in fact damage the sensor.
• If you have consumed alcohol even the night before, you should not use the breath ketone meter.
• Brushing your teeth, eating or drinking, or using mouth wash will all cause the ketone meter to give inaccurate results.
• A damaged sensor will give inaccurate readings. This can be caused inadvertently by blowing alcohol or mouthwash into it.

More information on how to get the best out of your breath ketone meter