Can a Keto Diet Actually Cause a Breathalyzer to Give a False Positive?

This story begins with a flight attendant who says he lost his job because a breathalyzer test administered by his employer, American Airlines, falsely said that he blew a positive result. The flight attendant says that he was on a “keto” or low carb diet, and that is why his results were inflated. His company accused him of drinking on the job. 

Did the flight attendant make a valid argument? The answer is yes. While a keto diet cannot make an individual go from 0.00 to 0.08, it will both inflate test results and show some alcohol in the system when there is not any.

What is Ketosis?

The keto diet is a low carb, high-fat diet that causes the body to burn fat instead of carbohydrates for energy. This results in rapid weight loss. Ketosis is the state where the body begins using fat for the majority of its energy. However, because ketosis can cause acetone to be traceable on the breath, and acetone is interpreted as alcohol by breath tests, the results of a breath test will not be accurate.

Here is how it works. Ketosis causes higher levels of acetone, which is broken down into isopropanol, an alcohol. In some cases, breathalyzers using electrochemical testing could not distinguish between isopropanol and drinking alcohol. 

Can Breathalyzer Tests Distinguish Between Ketosis and Drunkenness?

The information concerning ketosis and false positives has been around since 2006 when a study showed that an individual with no alcohol in their system registered a positive result on a breath test. However, not all breathalyzer tests are made the same and attorneys have been using ketosis as a defense now for 14 years. Since then, more advanced testing has resulted in breathalyzer tests that can distinguish between isopropanol and ethanol.

So, chances are, if your breathalyzer test was done at the police station, the police station has access to breathalyzer technology that does not conflate dieting with drunkenness. Of course, your lawyer will investigate the type of machine used to generate the results and then determine if the machine is capable of making that distinction.

Blood Tests

One of the main disadvantages of a breathalyzer test is that it has to convert breath alcohol into blood alcohol. One test that does not have to do this at all simply tests the blood for alcohol content. There is no apparent issue with mistaking isopropanol with ethanol.

Talk the Fort Wayne DUI Guy

If you are convinced the results of a blood alcohol test are wrong, you may be right. The attorneys at The Bellinger Law Office have seen that the slightest mistake in testing can result in false positives. Call today to learn more about how we can help you beat a DUI charge.