What body odors tell you about your health (and how they can be useful in detecting disease)

It was, obviously, nonsense. When a colleague mentioned a Scottish woman who claimed to have the ability to smell Parkinson's, analytical chemist Perdita Barran reacted this way. Barran says she thought, "Possibly she just smells old people and recognizes the symptoms of Parkinson's and makes some kind of connection." Joy Milne, a 74-year-old retired nurse, had approached Tilo Kunath, a neuroscientist at the University of Edinburgh, in 2012. The event took place while he was giving a lecture. Milne confided in Kunath that she had discovered her ability after noticing that her husband, Les, had acquired a new, musky scent years earlier. She was subsequently diagnosed with Parkinson's disease, a progressive neurodegenerative disorder characterized by tremors and other motor signs.