Keto Diets and DUIs

When most people get pulled over for suspicion of a DUI, they automatically think about whether they had any alcohol or how long it had been since their last drink.  Rarely do people think about their diet and how that could affect a breathalyzer test.

People may need to add this to a list of their concerns.  With society’s ever-increasing pressure to look fit and thin, a lot of people are turning to fad diets to accomplish these goals. However, some diets, like the Keto diet, may negatively impact a breathalyzer test and make it appear like a person is more intoxicated than they are.  

Low-carb diets, such as the newly popular Keto diet, involve eating little to no carbohydrates but eating more fatty foods. This way, when your body tries to burn carbs for energy, and there are none to be burned, your body burns fat for energy instead. This may sound like a good idea because it is effective and works fast, but this can cause surprising side effects for breathalyzer tests.

Can Ketosis Cause False Positive Breathalyzer?

Yes, when in ketosis, the body creates acetone as a byproduct, which is released through your breath in the form of isopropyl alcohol. A breathalyzer test will be will read the isopropyl as ethanol, which is used to make most alcoholic beverages

Your body likely won’t have enough isopropyl in it to cause a reading of above .08 on a breathalyzer test. However, a problem could arise if you had been drinking prior, even if it’s not enough to put you over the legal limit, because the isopropyl would cause a higher reading than your actual blood alcohol content would indicate.

If the officer has sufficient indicators to offer you a field breath test, or if you’re taking the breath test at the police station, you will likely be charged with driving under the influence if your results come back positive. However, a blood alcohol content test would not be subject to the same inaccuracies as a breath test and could prove a positive breath sample as false. 

Even though law enforcement officers may be aware of this possible false positive, they rarely ask questions to determine if the person is on a Keto diet before administering a breath test.

If you feel you are not under the influence of alcohol but on a Keto diet, it is important to request a blood alcohol test rather than a breathalyzer. The officer may not oblige, but at least your request would be noted if the officer is wearing a body camera, like all officers are required to wear in the District of Columbia, and could help you at trial. 

Even though the Keto diet may make you look your best when it comes to possible DUI charges, it may be best to stick with eating the cheeseburger and fries. 

If you have been charged with a DUI and believe the breathalyzer reading produced a false-positive result due to your diet, speak to our DC DUI attorney about your case and see what your options are. Contact Bruckheim and Patel for a free consultation of your case.

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