Surviving a Breathalyser Test while on a Ketogenic Diet

If you’re on a ketogenic diet and driving, then you should be aware of this

What is a ketogenic diet?

The ketogenic diet highlights a diet low in carbohydrates and high in fats with moderate protein. This unique combination alters the way your body uses energy. The abundant fat is converted to ketone bodies and fatty acids in your liver. Since your body is low in glucose, it will turn to ketone bodies for energy.

A ketogenic diet benefits a lot of people. These include people with diabetes, Alzheimer’s disease, some types of cancer, and epilepsy. It has certainly established its place for being successful in helping people who are overweight lose some kilos. Of course, most of us know the benefits of that.

Your heart, brain and muscles love ketones and use them to carry out their tasks. But they can only take in so much. This applies to other organs in your body as well. So, what does your body do when your tissues are full of ketones? It gets rid of them through your kidneys (urine) and lungs (exhaled air).

Unfortunately, the ketone acetone that is exhaled from the lungs is converted into isopropanol. Isopropanol is a cousin to the alcohol found in your alcoholic drink, ethanol and like ethanol it can be detected in your breath. Though the rate of isopropanol formation varies from one person to another.

A False Positive Breathalyser Test

Here’s where the problem lies. Are you familiar with a breathalyser? You should be if you’re on a ketogenic diet. A ketogenic diet can get you into unnecessary trouble if you’re not aware of its effect on a breathalyser. This happens when you get pulled over by a police officer and are asked to take an alcohol breath test.

A breathalyser is a device that roughly measures your blood alcohol levels through your breath. Drunk drivers are familiar with these wonderful devices. Unluckily for you, the one on a ketogenic diet, older models of breathalysers aren’t able to distinguish between ethanol and isopropanol. You may register positive for alcohol (false positive) on old breathalyser models and get arrested for driving under the influence of alcohol, even though you haven’t had any at all. Though some police officers out there are already using newer models that are able to differentiate ethanol from other types of alcohol.

Tips for what you can do about your ketogenic diet meeting an unfriendly and antique breathalyser:

Snap your system out of ketosis. Ketosis is the state wherein your body doesn’t have sufficient glucose for use as energy, so your body uses fats and ketones, with excess ketones being expelled through your breath. Before you get in your car, eat a piece of fruit like a banana or an apple. A cup of juice can also do the trick. This will be enough to temporarily kick your body out of ketosis and drop the levels of ketones in your breath. But hey, do this an hour before you leave for your trip. Not during your trip.
If an old breathalyser registers positive for alcohol. Explain your diet situation to the police officer like a normal, sober person would do. You’re not drunk, so don’t act like one. Politely ask for a blood alcohol test to confirm that there is no ethanol in your blood (provided you haven’t been drinking). Remain calm.
Don’t try to fool the breathalyser with different substances. Some people may try using mouthwash, denture cream, or even onions. You’re not guilty of anything illegal. You’re just on a ketogenic diet. Again, just discuss your diet situation with the police officer and ask for a blood test to prove your innocence, if necessary.
Don’t drink and drive. Whether you’re on a ketogenic diet, an “occasional” alcoholic beverage drinker, an ordinary citizen, or even a self-confessed alcoholic, DON’T DRINK AND DRIVE. Get a taxi or ask a friend or the angry wife (or husband) to pick you up. Your wife’s sermon on the way home is still better than losing a limb (or life) at the hospital.

Remember, if you’re on a ketogenic diet and you want to enjoy a drink, a mixed drink may be better than a plain spirit as the sugars will lower the ketones. This will avoid the combination of a small amount of alcohol and the ketones from tripping the breath test when you’re not actually over the limit.

The Bottom Line

Being on a ketogenic diet has its rewards. Getting caught with your ketones up and reasoning down might get you into a little bit of trouble. But there’s nothing to worry about, you know the solutions already. You certainly know why false positive readings happen. By the way, did you tell us why you got pulled over? Was it for speeding? Or driving like a drunk driver? Be smart, and be safe on the road.