The research, published today in npj Parkinson’s Disease, demonstrates that compounds or “volatiles” found in sebum—the oily substance produced by our skin—hold key biomarkers for identifying Parkinson’s in its earliest stages.

Using a technique known as Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC-MS), scientists at The University of Manchester, in collaboration with Salford Royal NHS Trust and University of Innsbruck, analyzed skin swabs from participants with Parkinson’s, healthy volunteers, and those with a sleep disorder called isolated REM Sleep Behavior Disorder (iRBD)—a known early warning sign of Parkinson’s disease.

The results showed that people with iRBD had distinct chemical profiles in their sebum that were different from healthy individuals, but not yet as pronounced as those with established Parkinson’s disease. This supports the idea that Parkinson’s disease leaves a detectable trace on the body well before physical symptoms appear.