woman holding a small glass bottle

What if humans were able to diagnose diseases through smell? While we know that some dogs can detect cancer this way, humans have a much weaker sense of smell that doesn’t usually allow for this (via Medical News Today). But there is one woman, Joy Milne, whose rare sense of smell allows her to smell Parkinson’s disease on a person, even before they know they have it. In fact, researchers have found that Milne can smell a range of diseases, including tuberculosis, cancer, diabetes, and Alzheimer’s disease (via NPR).

Parkinson’s disease is a progressive nervous system disorder. It causes stiffness and slowing of movement, tremors, loss of balance, and more. Parkinson’s takes a long time to develop, so many patients discover they have it after they’ve been struggling with symptoms for a long period of time (via Mayo Clinic). Milne’s sense of smell could allow patients to find out they have it before the onset of symptoms, opening up more options for treatment.

She noticed a change in her husband before his diagnosis

woman holding her nose

The first time Joy Milne smelled Parkinson’s disease on someone, it was her own husband. While she didn’t realize the significance at the time, she noticed a change in her husband’s smell a decade before his diagnosis. She says that he went from having a nice, male musk scent to a strong, nasty yeast smell. Milne originally thought his hygiene was slipping, but the smell wouldn’t go away. She eventually learned to ignore it (via the BBC).

After her husband began to show other symptoms, they went to the doctor to have tests done. They had originally feared it could be a brain tumor, but were then told he had Parkinson’s disease. After hearing the devastating news, Milne and her husband decided to join a Parkinson’s support group to help him better manage his new diagnosis. It was at one of these meetings that she began to realize what had been causing the strange smell coming from her husband for the past 10 years (via NPR).

Once she met others with Parkinson’s, she made the connection

people talking in a circle

At their first meeting with a Parkinson’s support group, Joy Milne walked into the room and immediately knew something was up. That smell she had only ever noticed on her husband now permeated the entire space around her. The realization hit her — she could smell Parkinson’s disease. She immediately told her husband after the meeting, where they both realized the potential medical significance of this discovery (via NPR).

Milne and her husband discussed her sense of smell with a Parkinson’s disease researcher, who initially didn’t believe she could possibly detect it through olfactory cues. Because Parkinson’s is a degenerative disorder, the idea that it could have a specific smell didn’t make sense. But he decided to give her a chance to test out her sense of smell. This eventually led to impressive results and allowed doctors to find biomarkers for the disease.

Doctors ran experiments to test Milne’s sense of smell

researcher using pipette and test tubes

In order to test Joy Milne’s sense of smell, researchers had 12 people wear a white T-shirt home overnight. Six of them had Parkinson’s, and six were part of a control group that did not. The team then numbered the shirts and had Milne blindly smell them and tell them if the person who wore them had Parkinson’s or not. She correctly identified all 6 of the people who had Parkinson’s and one person from the control group.

While researchers initially thought Milne may have misidentified the smell on one of the shirts, the man who wore it came back to researchers months later. It turned out he did have Parkinson’s and had just received a diagnosis. Milne had detected the disease in him eight months before he found out that he had the condition. This incredible finding led more researchers to contact Milne and enlist her in their own trials (via the BBC).

Milne is able to detect other diseases in addition to Parkinson’s

doctor pointing at kidney model

After the first groundbreaking experiment Joy Milne participated in, researchers from all over the world began to contact her for their own tests. Through all the research that Milne has participated in, she has found that she can smell other conditions in addition to Parkinson’s disease. These other diseases include diabetes, tuberculosis, Alzheimer’s disease, and even cancer (via NPR).

The conditions that Milne can smell are often hard to diagnose, so her ability may be able to help those who suspect they have one of them to get an early diagnosis. The earlier doctors can detect these diseases, the sooner patients can be treated, and the better the outcome can be. Milne works with researchers to this day to help find early indicators of a variety of diseases, including Parkinson’s. She has been able to use her unique sense of smell as an important tool for medical research.

Milne’s sense of smell is pioneering new medical research

medical professional swabbing a patient's nose

The research Joy Milne has been a part of has found a number of specific compounds that show up in higher concentrations in Parkinson’s patients. These compounds are found in oils on the skin, which explains how Joy is able to detect them. Since researchers have been able to use Milne’s sense of smell to discover these compounds, they have been able to create devices that can detect compounds in a lab, potentially allowing doctors to perform quick lab tests for Parkinson’s disease in the future.

Researchers mimic Milne’s nose using a device called a mass spectrometer. The mass spectrometer can find compounds in the skin’s oils that indicate potential Parkinson’s disease. While this research is still in development, if more compounds can be isolated for different diseases, doctors could eventually take a skin swab and be able to tell a patient whether they have Parkinson’s or another disease much more quickly than current methods allow (via the BBC).