How a Low-Carb Diet Can Trigger a False Positive Breathalyzer Test

Mar 16, 2022 | DUI Defense, Legal Advice

Driving Ketotic: How Low-Carb Diets Can Lead to False Positives on a Breathalyzer

If you’re trying to lose weight through a low-carb diet like the Paleo diet or the Atkins Diet, you might want to use a bit of extra caution behind the wheel—or maybe even get someone else to drive. As the International Journal of Obesity reports, a man in Sweden found out (amid much confusion and dismay) that a low-carb diet can actually produce false positives on a breathalyzer.

Fortunately for the Swedish man, he wasn’t being pulled over or tested by police; his car simply wouldn’t start. Ignition interlock devices are becoming increasingly standard in Georgia with the new Administrative License Suspension Laws that went into affect in July 2017.  This Swedish man’s breath triggered the on-board breathalyzer, locking the ignition. Remarkably, the Swedish man was completely sober.

Humorous as this story is, low-carb diets may be no laughing matter for drivers who trigger false positives at DUI checkpoints and routine traffic stops. We refer to this phenomenon as “driving ketotic”—that is, with a high concentration of ketones in the blood.

What Are Ketones, and Why Do They Matter?

According to Medical News Todayketosis is a natural metabolic process the body uses to burn stored fats as energy when not enough glucose is available through the foods we eat (caused by low-carb diets as well as diabetes). One of the by-products is a build-up of chemicals in the body called ketones. In higher concentrations, ketones can cause a number of complications in the body, even life-threatening in extreme cases. However, even in moderate concentrations, ketones may cause additional chemical reactions that produce isopropanol—which, as you might have guessed, is a form of alcohol. Thus, the false positives on the breathalyzer.


What Happens If You Trigger a False Positive?

If you trigger a false positive due to a low-carb diet, the bad news is that you could be arrested on suspicion of DUI. The good news is that if the test was done on a portable breathe test, and not the state administered test, the numeric reading can’t be used against you in trial.  It’s important you contact an experienced attorney because most officers will still arrest you based on the portable breathe test reading. You shouldn’t face a false DUI charge alone. For skilled legal representation, call Chehimi Law at 678-459-5659.