Monday, July 04, 2022

Dispelling Some Myths: A Short Life

 Average height

One of the misconceptions about history is that people were shorter ‘back then’. Would it surprise you to know that the average woman living in London in the Middle Ages was the same height as the average female Londoner today? In fact, according to World Population Review, in 2022 the average height of a British man is 5ft 10in (178.21 cm), while for a woman it is 5ft 5in (163.94 cm). neither is significantly different from people in the Middle Ages.

There are a couple reasons that might explain the misconception that people in the past were shorter: door heights and bed lengths. Neither are not good indicators of peoples’ average height, however. Doorways with low lintels, along with smaller windows, were common for heat retention in Northern European houses, while short beds were more about how people used to sleep. Lying flat was thought to be unhealthy so people slept partially sitting up, bolstered by pillows. Beds as a result were shorter. Neither example, however, does not mean that average heights were not shorter in some periods of history. 

During the reign of Queen Victoria (1837-1901), the industrial revolution saw the widespread movement of people from rural life on farms to life in the newly industrial cities. The rapidly increasing urban population led to malnutrition, vitamin deficiencies, and respiratory problems on a scale previously unknown. When measurements are taken of skeletons from cities in Victorian Britain, they prove to be significantly smaller than skeletons from the same cities in the period before and after. In the mid-19th-centrury the average man was only 5ft 5.7in (167 cm) tall (Parkinson, 2013). Since then, data collected on hundreds of thousands of men from 15 European countries has found that the average height of men has risen by almost 11 cm. For British men, the average height at age 21 rose from 167.05 cm (5ft 5in) in 1871-75 to 177.37 cm (5ft 10in) in the century to 1971-75.

The increase in average height observed over the years is the result of improving health. A study led by Professor Tim Hatton, a public health expert at the University of Essex, analysed data from sources including military records and modern population surveys from the 1870s to 1980 in 15 European countries [1]. The resulting paper, published in the journal Oxford Economic Papers, concluded that, while height was a ‘useful barometer’, it was crucial to focus on improving health overall.

Genes may be commonly seen as the main determinant of height, but although they explain the difference between individuals, they do not explain the study’s observed trend. The researchers said the gene pool ‘cannot account for substantial increases in mean stature over four or five generations’. But they also noted that growth is significantly affected by what happens in the first two years of life. So, a high rate of illnesses such as respiratory diseases or diarrhoeas - which caused many infant deaths - would also affect survivors' development and therefore their subsequent height. Interestingly, it was noted that infant mortality rates fell significantly throughout the period studied. As Professor Hatton explains there was no ‘Darwinian explanation’ to the trend, it is just that ‘people are surviving in the 20th-century who would not have survived in the 19th.’ 

Average life expectancy

That quote by Professor Hatton rather neatly leads us to another popular myth: that people in the past lived much shorter lives. While it is true that improved diets and better healthcare have dramatically increased survival rates since the beginning of the 20th-century, the same cannot be said of further back in time. However, once again there is a misunderstanding or misconception about average life expectancy.

If we take the Tudor period (mostly the 16th-century) as an example, we do not know exactly what the average life expectancy from birth was. Historians think it was about 35 years, with about 50% of the people born reaching that age, but that does not mean people simply dropped dead when they reached their 35th birthday!


By studying the official records of births and deaths, such as parish records, we can identify how many people were born and how many died in a given period of time. Moreover, we can often determine at what age they died. Now comes the seemingly tricky bit: calculating the average.

This is not nearly as complicated as it may appear [2]. In the two examples shown below, we have identified two groups of ten individuals whose ages at death are added together to give 455 and 210 respectively. Dividing the combined ages by ten (i.e. the number of individuals in the group) gives us the average life expectancy for each group.

The second group clearly has a much lower average life expectancy simply because the number of children who died young is greater. This is consistent with the following observations:

  • Average life expectancy at birth in the Tudor period was around 35, but a great many of those born died in childhood.
  • We cannot be certain of the exact percentage of those who died young. Yet we are probably not too wide of the mark with an educated guess of about one quarter of people, or 25%, died before they were 5 years old.
  • Perhaps as many as 40% (4 out of every 10 people) died before they reached adulthood.
  • If you did survive childhood and your teenage years, then it seems you had a good chance of living to your 50s or your early 60s.
  • In the 16th-century there are records of some people who even lived to 70 or 80.

A higher rate of infant mortality and deaths at an earlier age from disease and illness account for the much lower average life expectancy in the past compared to today. Yet, just because the average is statistically lower did not stop many people experiencing full lives into old age.

References:

Parkinson, C., (2013), ‘Men's average height 'up 11cm since 1870s', BBC News, available online (accessed May 10th, 2022).

Endnotes:

1. The study looked only at male height because there was too little historical data for women.

2. This despite the apparent difficulty far too many UK drivers have understanding the concept of average speed cameras.


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