Do Our Ears Get Bigger As We Age

Introduction

I remember attending a medical course a while back where the question came up of whether ears continue to get bigger as we age.
I think there is a widely held belief that they do and I suspect most people have anecdotal evidence in their own experience of older men in particular having larger ears.

That is not scientific research though and I wanted to see what if any literature there was on this subject.
I did manage to find a few studies but sadly most of them are not easily accessible.

Luckily one of the larger and more recent studies by Sforza et al. [1] is available on the DeepDyve subscription site.
NB - If you are not interested in reading about the study just scroll down to the "Conclusion" section to get the TLDR version.
The Study

843 Caucasian Italians aged 4-73 (see table below).
497 Male and 346 Female.
Subjects with a history of trauma, abnormalities or external ear pathology were excluded.
Anatomical points on subject ears were marked and digitised by computer (see image below).
Digitised points were then analysed to measure ear size and dimensions, ratios of length to width, area, angles and symmetry.
The 18-30 Age Group was used as the reference adult group to compare sizes with.

Results

Male Ears were generally larger than female ears.
Ears were smaller in childhood compared to the 18-30 adult reference group (length 90% in girls, 84-86% in boys aged 4-5 yrs) as one would expect.
Interestingly 15-17 yr old girls had longer ear length than the 18-30 group.
Ear Length, width and area increased in both sexes after age 30.
Generally ear length increased more than width, 3.2 times more in women, and 2.8 times in men.
Mean ear area (right) in Females at 18-30 was 927.30 mmsq, at age 65-80 was 1146.05 mmsq, a 24% change.
Mean Ear area in Males (right) at 18-30 was 1117.09 mmsq, at age 65-80 was 1451.66 mmsq, a 30% difference.
There also appeared to be some age related differences in measures of symmetry and angles in men particularly.
Positional asymmetry between both ears in both sexes was also noted.
The TLDR of the results - OLDER PEOPLE have bigger ears!

How Does This Fit With Other Research?

These results are certainly consistent with previous and other research.
The authors themselves cite several studies that apply to a variety of racial groups and are also consistent with their findings.

Although I was not able to access all the full papers I did have a quick look to see what I could find.
Due to time constraints I focused on more recent papers:

A study by Ferrario et al [2] reported the same finding of ears being larger in men than women and larger ear sizes in older individuals of both sexes.

Eboh [3] found a similar gender difference in size along with similar differences based on age in Nigerian individuals.

A 1995 study by Heathcote [4] in 206 general practice patients from the British Medical journal also shows similar relationships with age and ear length.

In a response to the Heathcote research Asai et al [5] presented their own findings in research carried out on primary care patients in Japan.

This study was notable because it tried to eliminate a possible confounding factor i.e. height which might influence the results.

They found that after adjusting for height the correlation of increasing ear size with age was even greater.
Problems

We should be careful though.
These studies and as far as I can ascertain the others to which they refer measure ear sizes of different individuals at a particular point in time and find that the older people have larger ears.

This is not the same as definitively saying that ears get bigger with age.

This is the age old problem of correlation NOT being the same as causation and is the major problem with this research
i.e. older age may correlate with larger ears but may not be the cause.
It may be that in the past for some reason people had bigger ears and some as yet unknown factor is causing them to change in size between generations.

The only way to know for sure would be to follow up a group of people over a longer period to confirm that people's ear's are actually increasing in size.
One final point is the use of a single racial group in this study. To be honest I don't think this is well explained in the paper - it may just be that the area that they were studying had less racial diversity.

It is not a huge problem since other research has shown similar correlations in other racial groups (which the authors themselves cite).
Anomaly in the Data?

An interesting anomaly in the data showed larger ear sizes in 15-17 year old girls (compared to the 18-30 group).
The authors mention this but don't really discuss it in any detail.

I am wondering if this could relate to ear piercing and the wearing of earrings? Could it also relate to a particular recent fashion for larger or heavier earrings?
There could also be other factors involved e.g. other cultural practices in this generational group, some environmental factor, illness disease etc.

It could also just be some kind of artifact that exists only in this particular population.
It would be interesting to see if further research replicates this blip in the data. Unless I have missed it I did not see any reference to it in any of the other research.

Why Would Ears Get Larger With Age?

A few theories have been put forward:
Ears start to sag and lose elasticity with age (much like many other tissues). The fact that length differences are greater would support this due to the effect of gravity.

Ears are primarily cartilage and it has been hypothesised that they may continue to grow throughout life.

Both this and previous studies suggest a faster rate of increase in men vs women. This would suggest a hormonal component to the change which may bear relation to either point 1 or 2.

A study by Isamu et al [6] supports age related changes that are more consistent with the first theory:
On morphological examination by light and electron microscopy after orcein staining, elastic fibers in the cartilage were almost homogeneous in diameter and surrounded the cartilage lacuna in bundle-like fashion in young persons,whereas those in elderly persons were heterogeneous in thickness and had many fragments surrounding the territorial matrix. In elderly persons, collagen-like fibers and small vesicles with heterogeneous electrondensity were frequently observed near elastic bundles around the territorial matrix.

Basically in the younger ears the elastic fibres were in a tidier and tighter arrangement. Fibres in the older ears had more damage and were less regularly arranged.

This suggests age related degenerative changes - sagging and loss of elasticity as the main difference.
Conclusion

The research suggests that older people DO have bigger ears and this is supported by multiple studies.
Further it is likely that these changes in size are due to age related degenerative changes in the cellular structure of the ear rather than conventional growth.
Whilst this suggests that ears get bigger as people age it would require a different type of study, namely a prospective study (where people are followed up over time) to confirm it.