German Study Finds Belly Button Odor May Distinguish Parkinson’s and Cognitive Decline
A small German study suggests that chemical signatures in belly button, nasal, and ear swabs could help distinguish Parkinson’s disease, mild cognitive impairment, and COVID-19 from healthy controls. Using laser spectroscopy, researchers found distinct volatile organic compound patterns in these hard-to-clean areas, offering a potential non-invasive screening tool, though larger trials are needed to confirm reliability.