Not sure if you’re weighing scales are working? Well now researchers have developed a new breathalyser that analyses your breath to detect if your body is burning fat.

The new device, powered by AA batteries, measures the amount of acetone in your breath, which is meant to be a good indicator of fat-burning.

New features include a pressure sensor that allows users to blow into it and two types of gas sensors that calculate acetone concentrations.

Researchers at Japan-based NTT Docomo, a mobile-phone provider, said it could help users find out if their dieting efforts are working and manage weight.

To test it, volunteers were split into three groups. The first made no changes to their lifestyle, the second took on light daily exercises, while the third restricted calorie intake and carried out the same routines.

Results showed that the acetone levels remained constant for those in the first two groups, while volunteers in the third group showed a significant increase in levels, meaning they lost significant amounts of fat.