Saliva test reveals signs of sleep loss ^{CEFR B2}

Researchers from the Institute of Forensic Medicine and the Institute of Pharmacology and Toxicology at the University of Zurich searched for direct metabolic markers of sleep deprivation in saliva. Until now, sleep loss could not be measured objectively in bodily fluids. The team tested whether a single saliva sample can reveal acute sleep deprivation under realistic conditions.

Twenty healthy young men who normally sleep seven to nine hours completed three experimental conditions in random order: one night without sleep, four consecutive nights of six hours' sleep, and a control condition with eight hours. The researchers analysed saliva using high-resolution mass spectrometry and applied machine-learning methods to screen tens of thousands of molecules for patterns linked to acute sleep loss.

They report that acute sleep deprivation affects about 10% of all biomolecules in saliva and identified ten biomarkers that reliably indicate fatigue. The patented biomarker set will be validated in a large international field study under realistic conditions. The field tests will include common real-life factors such as shift work, alcohol and medications. In the long term, the work could lead to a rapid on-site test to detect fatigue and so improve road and workplace safety. The study appears in the Journal of Proteome Research.