Were people shorter in the middle ages?

Question

In many castles or museums you'll find medieval armor, belonging to a knight. Those are often very small compared to the average human nowadays. I've heard this explained multiple times as being due to the general smaller size of people in the middle ages compared to the modern age. The reasoning was that the nutrition then was worse than today and that this affected the growth of the people.

Were people really so much shorter in the middle ages? If they were not shorter, why are the armors you see so small?

Answer 1

While this response does not directly answer the question, it may offer some insight into the phenomenon of larger stature within a single group over a period of time.

It is well-known that the average height of Dutch people has shot up in the last 60 years, from 5'7" to 6'1" for males and similarly for females. It is not fully understood why this is true, but there are several theories. An article in the Chicago Tribune offers some ideas:

• "More milk products, smaller families and better hygiene--those are the main reasons why the Dutch have increased in length"
• "I also think there must be something in our genetic makeup"
• "People with better incomes and higher educations are taller. Everywhere and always"
• "Komlos and other experts believe the answer lies in the uneven distribution of wealth in America and better access to health care in Europe"
• "the consensus among experts is that the country's excellent health-care system and a diet heavy on dairy products are the main factors responsible for the Dutch growth spurt"

Another article on Suite 101 offers some more interesting tidbits:

• There is a widely accepted evolutionary idea that each generation is fitter and taller than the last. This appears not to be the case at all. In Northern Europe, human height reached a high around 800 A.D., but then dropped to a low in the 17th century before climbing back up again.
• Two main factors seem to have caused this dip. The first was the growth of cities: the more people were clustered together, the less food there was to go round and the faster diseases spread; the second was the drop in global temperatures, during what is known as the Little Ice Age. Findings such as these have made it clear that human height is not just linked to genetics or diet, but is much more sensitive to a range of influences than was previously thought.
• "[S]tudies revealed that the Dutch growth spurt of the mid-19th century coincided with the establishment of the first liberal democracy"

One last article from the New Yorker is linked for your enjoyment.

To summarize, the shorter stature of the middle ages seems to be caused by: Crowded cities, poor nutrition, colder climate, disparity of wealth between the richest and poorest, and lower education levels. Hopefully this response is enough to show that "Yes, people really were shorter in the middle ages," and offer plausible clues as to the reason.

Answer 2

This is interestingly linked to the Flynn effect (secular trend of rising intelligence) in some of the literature.

In the case of at least one of the other trends, height, all four features of the IQ paradox have been documented, thus creating a “height paradox” identical to that seen in IQ. Even one of the earliest MZA [Monozygotic twins reared apart] twin studies of height, conducted in a U.S. population that was much shorter than today’s population, showed the reunited twins to be remarkably similar in height (Newman, Freeman, & Holzinger, 1937). This would sug- gest that whatever presumed environmental factor was stunting the population must have been so uniform in its effects that it did not matter whether monozygotic twins were raised in the same or different homes; they were still stunted to virtually the same enormous extent. Also, there is no evidence of any birth order effect in height (Ernst & Angst, 1983).

[...]

One major difference between research into the height and IQ trends, however, is that among researchers investigating the height trend, there is not the same general recognition that the high heritability of the trait poses theoretical problems for environmental hypotheses as there is among IQ researchers.¹

This is all from Mingroni (2007). He argues that heterosis / hybrid vigour / outbreeding elevation (basically the opposite of incest) is (part of the) the reason. Basically people are more mobile and no longer have to sex up their cousins, etc. It's been a while since I read the article, but it's a good review. According to him, most of what he says about IQ applies to height as well. I think he sums the evidence up fairly and Psych Review is a high-profile journal. The author is pretty elusive though – can't find out much about him.

¹ Mingroni, M. A. (2007). Resolving the IQ paradox: Heterosis as a cause of the Flynn effect and other trends. Psychological Review, 114, 1104.

Answer 3

It seems to have to do with childhood nutrition.

In their book "Generations," (Pp.175-176, 267), William Strauss and Neil Howe pointed out that one reason that Americans won the American Revolution was that their better nutrition made them two inches taller (5' 7'' vs. 5'5'') on average than the Redcoats, who were nearly two CENTURIES behind them in height. They also pointed out that the so-called World War II generation (born after 1900) was more than an inch taller, on average, than the generation born immediately before them (pre-1900). Two generations later, their children had grown another 3/4 inch, on average. Basically, the closer you get to "modern" (second half, 20th century) U.S. standards, the taller people get.

We are now seeing Asian children in ASIA, with 20th century U.S. nutritional standards catch up in height to American children, while their parents' nutritional standards and sizes were more like (U.S.) 19th century.

Answer 4

This question is answered by research conducted by Richard Steckel [2] taken from military records, and data on skeletal remains [1]

.. analyzed skeletal data from 30 previous studies. The bones had been excavated from burial sites in northern European countries, including Iceland, Sweden, Norway, Great Britain and Denmark. In most cases, the length of the femur, or thighbone, was used to estimate skeletal height. The longest bone in the body, the femur comprises about a quarter of a person's height.

The abstract from his 2001 paper says:

This essay places the debate over human welfare during industrialization in the context of very long-term economic developments by examining an important aspect of living standards--health and nutrition--since the Middle Ages. I use average stature determined from military records along with a neglected source, skeletal data. Average heights fell from an average of 173.4 centimeters in the early Middle Ages to a low of 165.8 centimeters during the seventeenth and eighteenth centuries. This decline of 7.6 centimeters exceeds by a factor of two any downturns found during industrialization in several countries that have been studied. Moreover, recovery to levels achieved in the early Middle Ages was not attained until the early twentieth century. The paper links the decline in average height to climate deterioration; growing inequality; urbanization and the expansion of trade and commerce, which facilitated the spread of diseases; the global spread of diseases associated with European expansion and colonization; and conflicts or wars over state building or religion. Because it is reasonable to believe that greater exposure to pathogens accompanied urbanization and industrialization, and there is evidence of climate moderation, increasing efficiency in agriculture and greater inter-regional and international trade in foodstuffs, it is plausible to link height gains that began in the eighteenth century with dietary improvements.

[1] http://researchnews.osu.edu/archive/medimen.htm

[2] Steckel R. Health and Nutrition in the Preindustrial Era: Insights from a Millennium of Average Heights in Northern Europe National Bureau of Economic Research Working Paper Series. October 2001.

Answer 5

Indeed however it is believed to be closely related to environment and nutrition, and not genetics changing over time.

One study that has been done in regard of human height is North and South Korea. People of both countries have same genetic make-up, history and common culture up until recently - which makes them an excellent study groups.

http://www.ncbi.nlm.nih.gov/pubmed/18647440

This paper investigates height and weight differences between the two Koreas by comparing national anthropometric data published by the South Korean Research Institute of Standard and Science with United Nations survey data collected inside North Korea in 2002. For socioeconomic reasons, pre-school children raised in the developing country of North Korea are up to 13 cm shorter and up to 7 kg lighter than children who were brought up in South Korea--an OECD member. North Korean women were also found to weigh up to 9 kg less than their Southern counterparts.