We Can Now Predict Disease With Smell
In 2015, Joy Milne made waves when it was revealed that she had an amazing talent – she could smell Parkinson’s Disease. And now she’s helping develop tests that could diagnose Parkinson’s long before symptoms begin to show.
Maybe start with some details about how accurate dogs’ sense of smell can be. And then segue into the fact that some people have a similar ability – and now that ability could save lives.
In a recent video, I talked about some superhuman senses that some animals have, and in it, I talked about the fairly well-known fact that dogs can actually smell some kinds of cancers.
So now you have a new anxiety when a dog buries its nose in your crotch.
The problem is dogs can’t talk, so it’s hard to figure out exactly what chemicals they’re smelling. And even the most accurate dogs were still in the 80% range.
But imagine if a person could have that ability, and could talk and could help discern exactly what chemicals they were smelling. That is exactly what’s happened in the case of Joy Milne, and thanks to her super smeller, we could be on the verge of a whole new suite of diagnostics tools that could save millions of lives.
Joy Milne is a retired nurse from Perth, Australia, who has kind-of had a superpower her whole life. And she had no idea.
Joy has something called hyperosmia, basically a superhuman sense of smell, her nose has more olfactory receptors than the rest of us.
Which kinda makes me think of tetrachromacy, where some people are born with 4 types of cones in their retinas instead of 3, so they have the ability to see colors a little more clearly than the rest of us.
So you could say Joy could smell in colors the rest of us can’t smell.
And this is something she never really thought about, you know, we all just assume that others perceive the world the same way we do.
Which is why it probably drove her crazy when about 10 years into her marriage, she started to notice a smell coming off her husband.
His name was Les, he was a doctor, and yeah, she started noticing a musky, yeasty smell coming off of him, and she assumed it was from something at work.
He of course couldn’t smell it, which isn’t unusual, we tend to go nose blind to our own smells, but to her it was just pungent, especially on his neck and upper back.
So she started telling him he needed to wash himself better. He did his best to oblige her but she kept complaining about it. I can only imagine the fun little arguments that that created.
She eventually just learned to live with it and tried to let it go because it was driving him crazy and besides, nobody else could smell it so… what can you do.
But a few years after that, she noticed his personality began to change.
As Joy told NPR in 2020:
“He was more moody. He wasn’t as tolerant.”
They began to fight more. All the good qualities she admired in him – patience and thoughtfulness – began to slip away.
By his early 40s, she saw her husband as a completely different person.
And then one night, she woke up to Les attacking her.
She told NPR:
“He was sort of screaming and shaking me… but he was totally oblivious of it.”
He was clearly just having a nightmare, but this was the breaking point. I’m sure getting attacked in the middle of the night could do that.
So Joy demanded he visit a doctor. She thought he might have a brain tumor.
Turns out, 45-year-old Les Milne had Parkinson’s disease.
Most of us know Parkinson’s disease as a brain disorder that can cause uncontrollable or unintended movements like shaking, stiffness, and difficulty with balance and coordination.
But people with Parkinson’s may also develop behavioral and mental changes, depression, and memory problems. And that was the case with Les.
The disease occurs when nerve cells in the basal ganglia are damaged or die. But scientists don’t know exactly what causes that.
Joy and Les made the best of things over the next 20 years, but as his condition deteriorated, it put a strain on their marriage, so they decided to join a Parkinson’s support group.
So they show up to this meeting, they actually got there kinda late. But when Joy walked in the room, a wave of that familiar smell came over her.
It took her a minute to realize that that smell was coming from the other people in the room.
Joy told NPR:
“And then I realized for some people it smelled stronger and for other people it didn’t smell so strong.”
She realized that maybe this thing that she’d been smelling this whole time was Parkinson’s disease.
And she’d been smelling it way before Les started showing any symptoms.
Both being healthcare workers, she and Les realized the implications of this. Because if you could start treating Parkinson’s before the nerve damage starts, you could save a lot of lives.
This was an amazing revelation. But what exactly are you supposed to do with that?
Well Joy reached out to a Parkinson’s researcher at the University of Edinburgh named Tilo Kunath.
And his initial reaction was probably exactly what you’d expect.
Wow, that is weird… Yeah… Well, I hate to cut this short but I’ve got a guy on the other line that can hear diabetes so thanks for calling, bye bye then.
Needless to say, it sounded a little crackpot to him at first but then he thought about the research that had shown that dogs could smell cancer – and he figured it couldn’t hurt to give it a look.
So he had her visit his lab for a special test. What he did was he took two groups of people, one group that had Parkinson’s and one that didn’t, and he had them wear white T-shirts for a night and seal them in boxes.
He then had Joy smell the shirts to see if she could identify the people who had Parkinson’s.
And the results were pretty mind-blowing. She got all of them right except for one – she had a false positive, she thought someone had Parkinson’s who didn’t.
But still, like 95/98% accurate, it was crazy.
Except that actually wasn’t true. Because a few months later that guy, that false positive guy… was diagnosed with Parkinson’s. She smelled it before he had any symptoms, and before it showed up on medical tests.
100% accurate. More accurate than established diagnostic tests.
So yeah, Dr. Kunath was on board at this point and continued to work with Joy. Unfortunately it was right about this time that Les’s health started to go downhill.
Les passed away in 2015. Before he died, he made Joy promise to continue researching and find a way to help others.
Joy and Dr. Kunath published their findings in ACS Central Science in March 2019. This spawned a lot of articles and specifically got the attention of a researcher named Perdita Barran.
Barran is a researcher from the University of Manchester Department of Chemistry and she wanted to see if they could figure out exactly which chemicals Joy was smelling.
So she and Joy started working together and they found several chemicals in the sebum, which is an oily discharge that we all have in our skin.
It’s often overproduced in people with Parkinson’s disease.
The research showed elevated levels of compounds like eicosane, hippuric acid, and octadecanal.
Using that info, Joy and a team of scientists from the University of Manchester developed a new skin swab test.
It works by swabbing the back of a person’s neck and back to collect sebum. Then a mass spectrometer analyzes it.
It can detect Parkinson’s disease with 95 percent accuracy under lab conditions.
The scientists sampled 79 people who had the disease and 71 healthy people.
They identified 500 compounds that were different between people with Parkinson’s and those without it.
Barran told the Hull Daily Mail:
“What we are now doing is seeing if (hospital laboratories) can do what we’ve done in a research lab in a hospital lab. Once that’s happened then we want to see if we can make this a confirmatory diagnostic that could be used along with the referral process from a GP to a consultant.”
The testing is still in the early stages, with a lot of refining still to be done.
Joy is also working with other scientists around the world to see if she can smell other diseases like cancer and tuberculosis.
By the way, Joy describes her super smell as a gift and a curse because, well for one thing a lot of perfumes and candles are overwhelming to her, I can imagine that’s annoying but also… it creates some ethical issues.
Because sometimes when she’s walking down the street or shopping in the supermarket, she’ll walk past somebody… And she can smell Parkinson’s on them.
So what do you do in that situation? Do you say something? How would that go?
“Excuse me, ma’am, can you hand me that box of Corn Pops? Thanks. Oh, you probably have an undiagnosed terminal illness, okay bye…”
Like seriously, what are you supposed to do?
Joy consulted with medical ethicists and said she probably shouldn’t say anything. For now anyway.
Because the research is still new, it’s not in laboratory conditions and there are also privacy issues involved.
Besides, what are they supposed to do, go to their doctor and demand a test because some random lady at the store said they smell like Parkinson’s?
But maybe in the future the smell test will pass the… smell test. We’ve known that different diseases have different smells for a long time.
The ancient Indian medical text Sushruta Samhita even includes the line:
“By the sense of smell we can recognize the peculiar perspiration of many diseases, which has an important bearing on their identification.”
In Chinese medicine, there’s a practice called Listening and Smelling, or Auscultation and Olfaction.
They basically assign sounds and smells to the different organs in the body. And changes in those smells could indicate problems in those organs.
And the same is true to a lesser extent in Western medicine. Smells have often been a diagnostic tool.
For example, if a patient had a fruity aroma of decomposing apples, an experienced diagnostician would know they probably have diabetic ketosis.
Back in the day the smell of baked bread coming off a person was a sign of typhoid fever.
hyperaminoaciduria – dried malt or hops
scrofula – stale beer
And Yellow Fever apparently smells like a butcher shop. So good luck getting a date when you smell like that! And you know, the yellow fever.
Now at this point you might be asking me, “Why Joe? How exactly do diseases make different smells?” To which I would respond by saying why are you talking like that?
To put it simply, our bodies are basically chemical factories, and diseases alter those factories, and the chemicals it creates.
For example, a pathogen could alter the level or types of microbes, which expirate different chemicals that we can pick up through smell.
Or, the activation of our immune system could change the excretion of metabolic byproducts from our hormonal system.
And there is one smell test that has made its way into the clinic, it’s a test for asthma.
When the airways in our lungs are infected, they release nitric oxide in a person’s breath. And those levels are higher in people with asthma.
Well, after two decades of development, the FDA approved a handheld device that doctors now use to help make a diagnosis.
This is a cool first step, but now they’re working on similar technology for personal use that could let you monitor medication effects and or even give advance warnings of asthma attacks.
It could even plug into a mobile phone, with an app reporting on nitric oxide levels.
As Raed Dweik, a physician and professor at the Cleveland Clinic, told Scientific American in 2016:
“Your phone would become the device. That’s the future.”
So it is possible in the not too distant future that you could take a scent sample as part of your yearly physical exam.
And that sample could be analyzed to find everything from Parkinson’s to cancer, Alzheimer’s, heart disease, you name it.
And with those early warnings you could start treating and fending off the disease long before they actually become a problem.
And along with that, devices that work with your phone to give you early warnings of problems in your daily life.
It really could be the beginning of a whole new way to see disease, far earlier than our eyes could detect.
All because of one woman and her superhuman sense of smell. Really cool stuff.