A very low calorie diet or a high protein, low carbohydrate diet causes certain changes in the way the body manages and creates its energy. When carbohydrates are restricted, the body does not have sugar or starch from which to create glucose, which it needs for survival. So the body creates glucose from protein instead.
This process results in the creation of ketones, which spread throughout the body. The body uses some of the ketones for energy. But the body keeps making more ketones as it continues to produce glucose, and the excess ketones are released- including from the lungs, as a form of alcohol, and straight into a breath test machine. For this reason, a low carb diet may very well be to blame for a surprisingly high breath test report or a false positive. A knowledgeable DUI attorney can help you challenge the unfair result, so it is important to discuss any special diet that you were on at the time of your breath test result with your lawyer.