The Science of Earwax: It May Help Detect Cancer, Diabetes, and Other Diseases

Earwax contains a treasure-trove of information about our health—including cancer status.

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We all likely take earwax for granted—and prefer to not think about it. However, the under-appreciated substance does more than keep your ears clean and free of debris—scientists have discovered that it contains a goldmine of health data. Beyond that, earwax might be able to signal diseases like diabetes and cancer.

Cerumen is the technical term for earwax. Ceruminous and sebaceous glands secrete a substance in the external auditory canal that mixes with sweat, hair, dust, and other debris. The purpose of cerumen is to keep the ears lubricated and clean and create a barrier to discourage the entry of bugs and other foreign objects that might infiltrate and wreak havoc.

In 2006, a landmark study discovered that earwax varies between people, identifying a single nucleotide polymorphism (SNP) that determines what type of earwax a person has—wet or dry. Of note, a SNP (pronounced “snip”) is the most frequent type of genetic variation among people, and each SNP signifies a difference in a single DNA building block (nucleotide).

Subsequent work found that earwax type also varies among different ethnic groups. Dry earwax is prevalent among East Asians, and the wet type is most common among those of European and African descent.

Interestingly, the gene that determines earwax type is also responsible for whether your armpits smell, and those with the dry type generally produce less sweat and body odor—traits found more in East Asian populations.

The Science of Cerumen

In recent years, earwax has gone from a relatively untapped biological resource to the focus of scientific study, particularly diagnostics.

In 2019, scientists developed a new way to detect cancer using earwax, publishing their findings in Nature. The researchers called the new method the Cerumenogram. The study collected earwax from two groups: people with cancer (lymphoma, carcinoma, or leukemia) and those without cancer.

When tested, 27 biological markers contained in the earwax were able to discriminate between cancer patients and healthy controls 100 percent of the time. The new test has the potential to be a quick, noninvasive, inexpensive, and highly accurate test for cancer diagnosis.

In a subsequent study, published in April, the authors expanded on their findings, demonstrating the Cerumenogram’s effectiveness in detecting metabolic changes associated with cancer.

Nelson Roberto Antoniosi Filho, a professor of chemistry at the Federal University of Goiás in Brazil and an author of both studies, explained the findings and their implications for finding cancer early.

In 2019, he and his colleagues demonstrated that earwax could be used to diagnose any cancer at any stage, which they have since verified by studying more than 1,000 samples, he said. Their most recent research shows that the same method can detect pre-cancer stages, diagnose metabolic remission of cancer, and distinguish between benign and malignant tumors.

Filho says he and his colleagues have found that their method detects cancer earlier than traditional tests or expensive imaging, meaning that treatment can start sooner, be less aggressive, and cost less—often before the cancer fully develops—significantly improving the chances of success. For patients in remission, it also clearly shows the moment they are cured, ending years of anxiety and uncertainty, which often lasts for five years or more of follow-up.

He says he and his team are currently focusing their studies on metabolic disorders like diabetes mellitus, xeroderma pigmentosum, cancer, and Parkinson’s and Alzheimer’s diseases. They are also beginning to focus on autism and depression.

“The range of usefulness of earwax has surprised us with each study, and we are sure that the Cerumenogram will become a routine assay with multiple applications for human health and that of other animals,” Filho told The Epoch Times in an email.

A Self-Sampling Device

A 2020 study led by Dr. Andrés Herane-Vives, a psychiatrist, scientist, and lecturer at University College London and King’s College London in the UK, collected earwax and measured for cortisol, comparing it with standard measurements using hair. Although hair samples are typically used to measure long-term cortisol levels in chronic stress or endocrine dysregulation conditions, the study’s results indicated that using earwax samples may yield more accurate results.

In another 2020 study using earwax, Herane-Vives and his team found that glucose levels reflected in earwax matched levels found in blood and that earwax glucose reflected short- and long-term blood glucose with 59 percent more accuracy than the HBA1c test, the standard blood test used to measure blood sugar levels as well as for monitoring and diagnosing diabetes.

Herane-Vives explained why earwax is unique and offers a more complete picture for tracking certain conditions over time.

“We needed a new specimen to reflect chronic levels of different biomarkers, because so far, the samples that we’ve got—like saliva, urine, or blood—are not able to accumulate substances, and only give us a snapshot,” he told The Epoch Times.

One of the ways earwax was collected in both studies was using a self-sampling device that Herane-Vives has since further developed through his biotech company, Trears Biomarkers. The device allows patients to collect their earwax in the comfort of their homes, and then mail it to a lab for analysis.

The Earwax Self-Sampling Device developed by Trears Biomarkers. Courtesy of Dr Andrés Herane-Vives

Herane-Vives says the future of cerumen research and Trears, is to improve diagnosis so people get the treatments they need.

“We don’t need new treatments; we need better diagnosis,” he said.

The device could change the game for many patients with chronic diseases like diabetes, allowing them to collect samples at home for regular testing, making the process easier, more reliable, and vastly less expensive, in addition to easing an enormous financial burden on the health care system.

The only challenge of using earwax may be that some people lack a sufficient amount, making testing difficult.

“A few people produce little earwax or don’t produce earwax at all. In this regard, we are also finalizing studies to overcome this problem,” Filho said.

The combination of tests like the Cerumenogram and self-sampling devices that allow people to collect their earwax without having to visit a doctor’s office or lab offers an exciting vision of the future of medicine.

Filho said there is no doubt that earwax analysis will become routine in the coming years.

In Brazil, the approach is already being used to diagnose tumor development, including both cancerous stages and pre-cancerous conditions, as well as to assess whether the cancer is in remission, he said.

“This examination has been routinely applied in one of the largest oncology hospitals in the country or Hospital Amaral Carvalho (Jaú-São Paulo), and we are working to ensure that in the next five years, all public educational and research institutions in the country offer this examination at the lowest possible cost to the entire population,” Filho said.

For the rest of the world, he said, the Cerumenogram will become as common as a blood test within the next decade.

“Perhaps in the future, while we listen to music through headphones, those headphones will diagnose our health conditions and tell us what precautions we need to take. I suggest that a samba be played to indicate that health is good!” Filho said.