Why do ears and nose grow when we are old?
In the early 1990s, a group of English doctors set out to study whether the perception that ears and noses grow over time was true. In 1995, the results of this research were published: thanks to the analysis of the measurements of more than 200 people, the proportional relationship between age and length of the ears was found, and the growth rate was established at about 0.22 mm per year.
Although they are the only structures that continue to increase in size after adolescence, this growth is not real. The ears and nose, among other structures of the human body, are made of hyaline cartilage, a type of hard connective tissue that does not contain nerves or blood vessels. Within this cartilage, collagen fibres are arranged in a special way that gives them their characteristic elasticity. Over the years the matrix where the fibres are placed undergoes different changes and, because there is no blood supply, the structure of the cartilage degenerates. These modifications to the internal structure of the ears and nose, which are also aggravated by the force of gravity, give them a thicker and more elongated appearance. They are indeed larger but not because their structure is developing.
These morphological changes are responsible for voice changes in old age but do not affect our sense of hearing. They appear without any distinction regarding sex or ethnic group and have been studied by forensic medicine to be used to determine the age of adult subjects.
Answered by Àngels Royo Peiró, graduate in Medicine and specialist in Medical Oncology. She is currently working as a doctor in an elderly people’s residence.
Question submitted by Diego Ortega Garcia.
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