Guiding Ketogenic Diet with Breath Acetone Sensors

Sensors (Basel). 2018 Oct 28;18(11):3655. doi: 10.3390/s18113655.


Ketogenic diet (KD; high fat, low carb) is a standard treatment for obesity, neurological diseases (e.g., refractory epilepsy) and a promising method for athletes to improve their endurance performance. Therein, the level of ketosis must be regulated tightly to ensure an effective therapy. Here, we introduce a compact and inexpensive breath sensor to monitor ketosis online and non-invasively. The sensor consists of Si-doped WO₃ nanoparticles that detect breath acetone selectively with non-linear response characteristics in the relevant range of 1 to 66 ppm, as identified by mass spectrometry. When tested on eleven subjects (five women and six men) undergoing a 36-h KD based on the Johns Hopkins protocol, this sensor clearly recognizes the onset and progression of ketosis. This is in good agreement to capillary blood β-hydroxybutyrate (BOHB) measurements. Despite similar dieting conditions, strong inter-subject differences in ketosis dynamics were observed and correctly identified by the sensor. These even included breath acetone patterns that could be linked to low tolerance to that diet. As a result, this portable breath sensor represents an easily applicable and reliable technology to monitor KD, possibly during medical treatment of epilepsy and weight loss.

Keywords: biomedical; breath analysis; chemical sensor; flame spray pyrolysis; nanotechnology; point-of-care; semiconductor.

MeSH terms

  • Acetone / analysis*
  • Breath Tests / instrumentation*
  • Calibration
  • Cohort Studies
  • Diet, Ketogenic*
  • Female
  • Humans
  • Ketosis / blood
  • Ketosis / diagnosis
  • Male
  • Young Adult


  • Acetone