14.07.2025 – Bristol , UK
That dogs have an extraordinary sense of smell is well known—but new findings are surprising even to scientists. In a recent study from the UK, researchers trained two dogs to detect Parkinson’s disease using skin samples. The result: the animals were able to distinguish affected individuals from healthy ones with up to 80% accuracy.
Changes in skin sebum
Skin swabs from a total of 100 individuals were tested—including 40 people with Parkinson’s who had not yet started medication. The dogs sniffed their way through the samples without knowing which belonged to whom. In this so-called double-blind study, they not only achieved high detection rates but also correctly ignored over 90% of the control samples. What the dogs are detecting is likely a specific combination of metabolic byproducts in sebum—a kind of biochemical fingerprint that changes with Parkinson’s. The scent is reportedly so distinct that even people with an exceptionally keen sense of smell—so-called “super-smellers”—can perceive it.
Interpretation
The results are promising, even though they are based on a relatively small sample size and only two dogs successfully completed the training. Differences between the animals also highlight how much individual learning and training outcomes can vary. Still, the study provides important evidence: Parkinson’s disease measurably alters body odor—even before medication begins. This lays the groundwork for the development of diagnostic technologies that detect volatile biomarkers in sebum. The ultimate goal is to create so-called “electronic noses” that could one day enable early, affordable, and non-invasive diagnosis.
Pic: VetDynamics
