Texas residents who are trying to lose weight often turn to diets low in carbohydrates because they cause the body to go into a metabolic condition known as ketosis. Without carbohydrates, stores of glucose are depleted quickly and the liver begins to burn fat to provide the body with energy. While this may be good news for those hoping to shed a few pounds, some experts say that it could also lead them into trouble if they are pulled over by police and asked to submit to a breath test.

This is because acetone is produced when fat is burned by the liver, which can lead to a buildup of isopropyl alcohol in the breath. The companies who make portable breath-testing equipment for police departments deny that ketogenic diets can trigger the devices, and they point out that the results of roadside tests are not generally used as evidence in drunk driving cases.

However, roadside breath tests do provide police officers with reason to detain motorists suspected of driving under the influence and transport them to law enforcement facilities for more thorough testing. These tests are usually performed using infrared spectroscopy equipment. While the amount of isopropyl alcohol in the breath of individuals on ketogenic diets would not produce a blood alcohol concentration of .08 percent even if the device used misidentified it as ethanol alcohol, it could leave low-carb motorists who consumed one or two drink before getting behind the wheel in a difficult situation.

Breath-testing equipment can produce misleading results for a variety of reasons, and attorneys with DWI defense experience may check police maintenance records carefully and ask their clients medical questions when BAC evidence seems questionable. This is because several common medical conditions including diabetes can cause inaccurate BAC readings and breath-testing equipment that has not been properly serviced may produce inaccurate results.