Earwax, scientifically known as cerumen, is a natural substance present in the human ear canal. It serves a protective function, maintaining ear health by trapping dust and other small particles. This waxy material also lubricates the ear canal and helps prevent the growth of bacteria and fungi. It plays an important role in the ear’s defense system.
Key Ingredients
Earwax is a complex mixture primarily composed of secretions from two types of glands located in the outer part of the ear canal. Sebaceous glands produce an oily substance called sebum, which contains fatty acids, cholesterol, and squalene. Ceruminous glands, which are modified sweat glands, contribute waxy esters and other less viscous secretions. These glandular contributions give earwax its characteristic consistency and some of its protective properties.
Beyond glandular secretions, earwax incorporates shed skin cells from the lining of the ear canal. Approximately 60% of earwax consists of keratin, a protein found in these dead skin cells. Fine hairs from the ear canal and external debris such as dust and dirt also become embedded within the cerumen, creating a protective barrier.
How Earwax Forms and Clears Itself
Earwax is continuously produced in the outer one-third of the ear canal, where the sebaceous and ceruminous glands are located. The secretions from these glands mix with dead skin cells that are constantly shed from the ear canal lining.
The ear possesses a self-cleaning mechanism that gradually moves earwax outwards. This process, often compared to a conveyor belt, involves the slow migration of skin cells from the eardrum towards the entrance of the ear canal. As new skin cells form, older cells, along with the trapped earwax and debris, are pushed out. Everyday jaw movements, such as chewing and talking, assist in dislodging and propelling the earwax towards the outer ear, where it can naturally fall out.
Differences in Earwax
Human earwax typically falls into two main types: wet and dry. Wet earwax is generally sticky and can range in color from honey-colored to dark brown. In contrast, dry earwax is flaky and often appears gray or tan. This distinction is primarily determined by a single genetic variation.
The ABCC11 gene plays a significant role in determining earwax type. Individuals with a specific variant of this gene produce wet earwax, which contains a higher lipid content. Another variant of the ABCC11 gene results in dry earwax, characterized by a lower lipid concentration. The prevalence of these types varies across different populations, with dry earwax being more common in East Asian populations, while wet earwax is more prevalent among people of European and African descent.