Skip to main content
Move the World.
cortisol levels

Lead Image © SciePro / Adobe Stock

When you get stressed, your body produces a hormone called cortisol, which triggers the "fight or flight" response that has helped humans respond to threatening situations since our caveman days.

Usually, cortisol levels return to normal once the scary situation is resolved, but some people have chronically high (or low) levels of the stress hormone in their bloodstream.

Abnormal levels have been linked to depression, adrenal gland disorders, and other health problems — but currently, it's hard for doctors to actually measure them.

Some tests measure cortisol levels in blood, saliva, or urine samples, but those only provide a glimpse at current levels, which can radically fluctuate based on everything from what a person recently ate to their exercise routine. Hair tests are better, but they're tricky and expensive to analyze.

Now, researchers at University College London have identified earwax as a promising target for cortisol testing — and developed a device that allows patients to extract their own samples at home.

Trears for Ears

The earwax-sampling device is called Trears, and it looks like a tiny wand with a spongy cylinder at the end.

To use it, a person inserts the spongy part into their ear like they would a cotton swab. A stopper prevents the device from entering too far, potentially causing damage, and a solution on the sponge aids in the collection of earwax.

After swabbing, a person would send the sponge into their doctor to have the cortisol levels in their earwax measured.

Because earwax is resistant to bacterial contamination, the sample is unlikely to be compromised en route, according to the researchers.

cortisol levels

The Trears device for collecting earwax samples. Credit: Trears

Measuring Cortisol Levels

The researchers conducted a study with 37 people to see if the device could effectively sample cortisol levels.

They started by collecting samples from the participants' left ears using a traditional (and painful) method. A month later, they repeated that process, but also had participants collect samples from their right ears using the Trears device.

The researchers also collected hair samples from all of the participants, as well as blood samples.

"It’s easy to take a sample and get it tested quickly, cheaply, and effectively."

Andres Herane-Vives

After comparing all of the sources, they determined that the cortisol levels in the earwax appeared to be more stable. It also took less time and money to analyze the earwax samples than the hair.

As for getting at that earwax, participants in a previous study had reported that the Trears method was more comfortable than the traditional one.

"(W)ith our new device, it's easy to take a sample and get it tested quickly, cheaply, and effectively," lead researcher Andres Herane-Vives said in a news release.

He and his colleagues acknowledge the need for larger trials to test Trears' ability to help with cortisol testing, but they're already considering other uses for it, including glucose monitoring for people with diabetes.

The researchers are even looking into whether it's possible to use earwax to measure COVID-19 antibodies — and if so, people wouldn't even need to leave their homes to submit samples for testing.

We'd love to hear from you! If you have a comment about this article or if you have a tip for a future Freethink story, please email us at [email protected].

Up Next

Dispatches
The Eternal Sunshine of the Stressed Out Mind
The Eternal Sunshine of the Stressed Out Mind
Dispatches
The Eternal Sunshine of the Stressed Out Mind
Researchers at Cambridge University have finally figured out how the brain stops stressful thoughts and memories...

Researchers at Cambridge University have finally figured out how the brain stops stressful thoughts and memories from taking over our minds.

Dispatches
Linking Genes to Depression Could Revolutionize Treatment
Linking Genes to Depression Could Revolutionize Treatment
Dispatches
Linking Genes to Depression Could Revolutionize Treatment
Saying something is “genetic” used to be a fatalistic diagnosis. But with modern medicine, it could be the key to...

Saying something is “genetic” used to be a fatalistic diagnosis. But with modern medicine, it could be the key to treatment.

Future of Medicine
Reading Your Digital Signature to Detect Depression, Parkinson’s
Digital phenotyping mental health disorders
Future of Medicine
Reading Your Digital Signature to Detect Depression, Parkinson’s
Digital phenotyping uses our smartphones to detect anything from Parkinson's disease to mental health disorders.

Digital phenotyping uses our smartphones to detect anything from Parkinson's disease to mental health disorders.

Biohacking
Treating Depression at Home with a tDCS Headset
tdcs device for depression
Biohacking
Treating Depression at Home with a tDCS Headset
At-home tDCS headsets are helping people treat their depression without having to go to a doctor’s office.
By Sarah Wells

At-home tDCS headsets are helping people treat their depression without having to go to a doctor’s office.

Dispatches
Mental Training Can Heal Traumatic Brain Injuries (and Reduce Depression)
how to heal the brain
Dispatches
Mental Training Can Heal Traumatic Brain Injuries (and Reduce Depression)
Millions of people are dealing with traumatic head injuries; brain scans show that cognitive training could...

Millions of people are dealing with traumatic head injuries; brain scans show that cognitive training could actually repair damaged neural connections.

Mental Health
Can Sleep Deprivation Cure Depression?
Can Sleep Deprivation Cure Depression?
Watch Now
Mental Health
Can Sleep Deprivation Cure Depression?
Losing sleep can have a lot of adverse health effects, but recent science shows it could also have a surprising upside
Watch Now

Studies show that loss of sleep can lead to memory loss, compromised immunity, weight gain, and mood swings. However, scientists are now finding that sleep deprivation may be used to treat depression. Losing sleep has the opposite effect on those struggling with depression. It restores the circadian rhythm that is usually flat in depressed people and it helps balance the parts of the brain that regulate mood. Unfortunately,...

Mental Health
Remote Therapy Is As Effective As Face-to-Face, for Depression
remote therapy
Mental Health
Remote Therapy Is As Effective As Face-to-Face, for Depression
The pandemic has therapists' couches off limits. A new study finds that remote therapy may be as effective for depression as face-to-face, so I gave it a try.

The pandemic has therapists' couches off limits. A new study finds that remote therapy may be as effective for depression as face-to-face, so I gave it a try.

Mental Health
Can AI Predict Which Depression Treatment is Most Effective?
Depression Treatment
Mental Health
Can AI Predict Which Depression Treatment is Most Effective?
Artificial intelligence-powered algorithms that analyze brain scans are showing promise in helping doctors find an effective depression treatment on the first try.

Artificial intelligence-powered algorithms that analyze brain scans are showing promise in helping doctors find an effective depression treatment on the first try.

Dispatches
FDA Approves First Mute Button for Genetic Diseases
FDA Approves First Mute Button for Genetic Diseases
Dispatches
FDA Approves First Mute Button for Genetic Diseases
It is the first of "a wave of advances that have the potential to transform medicine."

It is the first of "a wave of advances that have the potential to transform medicine."