A new study shows that measuring long-term cortisol levels from earwax may be a more accurate and easier diagnostic tool than using a hair sample. The latter is the current gold-standard biomarker used to measure cortisol levels in the body.

Key Takeaways

  • Earwax can be a biomarker for measuring cortisol, glucose, and possibly other lab values.A novel self-sampled earwax device is being produced to safely and effectively extract an earwax sample.

The November study, which was published in the journal Heliyone, compared hair cortisol concentration, serum (blood) cortisol concentration, and earwax cortisol concentration in 37 healthy participants. Researchers found that earwax not only had a higher concentration of cortisol–also known as the stress hormone–but was also the fastest and cheapest technique out of the three samples taken.

High cortisol levels over a long-term period have been associated with a number of conditions including depression, anxiety, heart disease, and obesity. But chronically high cortisol levels have been difficult for doctors to pinpoint in order to make a proper diagnosis due to a fluctuation in variables like:

  • Food intakeAlcohol consumptionExerciseSystemic stressors

“We still need more studies to find out the significance of measuring cortisol levels using earwax,” Andres Herane-Vives, MD, lead study author, and visiting researcher at the Institute of Psychiatry, Psychology and Neuroscience at King’s College London, tells Verywell. “This lab test is to provide support, and the ability to make a more accurate diagnosis.”

Self-Sampling Earwax Device

A new novel self-sampling earwax device, produced by a company called Trears, was used in the study to extract earwax from the right ear. A Reiner-Alexander syringe was used to extract earwax in the left ear. Researchers found that the self-sampling device, which is similar to a cotton swab but designed with a break to prevent eardrum damage, proved to be a more efficient, faster, and economically viable measuring technique than the syringe. They say it serves as an easier way to deliver an earwax sample to laboratories.

What This Means For You

In the future, you may be asked to give an earwax sample as part of an exam to measure critical lab values in your body. In the meantime, you should refrain from putting any objects in your ear—including a cotton swab. It is dangerous and can not only damage the eardrum, but also push earwax further into the ear canal. 

“At some point, we would like this device to available to the public to provide an accurate diagnosis and help with treatment,” Herane-Vives, who is also a founder of Trears, says. “That is not part of the first stage, but maybe down the road.”

What Exactly Is Earwax?

Eearwax (also called cerumen) is an oily secretion transported from the ceruminous glands into the auditory canal. It cleans, lubricates, and protects the ear canal by trapping dirt and slowing the growth of bacteria. Earwax has antimicrobial effects which may aid in its ability to accurately reflect long-term systemic cortisol levels. Other samples, including saliva and urine, can be contaminated by bacteria.

Researchers involved in the study and the creation of the self-sample earwax device believe that earwax can potentially be used as a tool to test many biomarker substances including:

  • Glucose for measuring chronic glycemia over a monthDrug dependenciesChronic cholesterol levelsAddison’s diseaseCushing syndromePossibly even COVID-19 antibodies that might accumulate in ear wax