Researchers have created a handheld breathalyser that measures acetone in breath to show when the body switches to burning fat for energy. The device, called Nutrion, is already commercially available and was developed at ETH Zurich in Switzerland.
Andreas Güntner and colleagues at ETH Zurich built the tool to address limitations in existing methods like bathroom scales or blood tests. It uses an acetone-specific sensor and filters to handle moisture and interfering compounds, with a smartphone app guiding users on breathing technique.
Tests with 12 volunteers under varied diet and exercise conditions showed the readings matched laboratory breath acetone and blood ketone measurements. The device detected small metabolic shifts, such as rising acetone after intense exercise and immediate drops after a sugary drink or carbohydrate meal.
Güntner noted that the tool could aid dieting, intermittent fasting and ketogenic diets. An ongoing trial is assessing its use for monitoring epilepsy treatment in children, where repeated blood tests are currently standard.
Dirk Dugdale-Duwell of Elevate Performance Testing said the approach could ease home monitoring for patients and athletes seeking to adjust carbohydrate intake based on real-time metabolic data.
