Roderick Floud: Costume dramas give a false picture of the size people used to be

What are the most obvious changes to have occurred in the shape of the human body in recent centuries? TV costume dramas are notable for their attention to detail, to the most minute aspects of costume or furnishings. But there is one aspect of the past which, unavoidably, they get wrong. The actors are too tall and, usually, too fat, properly to portray historical characters.

We know this because, over the last 30 years, I and my colleagues in the discipline now known as anthropometric history have collected enormous amounts of information about the heights and, where available, the weights of people in past societies.

This has enabled us to map, in time and space, changes to average height and sometimes to average weight and body mass, in many societies at many different stages of economic development. This evidence can easily be compared with the position today because we know that, in all societies, human growth follows a common pattern, most easily shown on the growth charts against which all modern babies are monitored.

One difficulty in discussing these changes is that they seem to be small, a matter of only a few inches or centimetres in several centuries. In reality, they are large, for three main reasons. The first is that we are extremely good at assessing the heights of other people, whether individually or in groups, and that we can perceive differences which are only of a few centimetres; if any of you have visited China or the Netherlands, you will probably have felt tall in the former, short in the latter. The second reason is that height is extraordinarily sensitive to a variety of influences which I will discuss, so that apparently very small differences can be both actually and statistically significant. And the third reason is that we are observing changes to averages, to summary measures of underlying distributions of changes which have occurred to very large numbers of people.

This is an extract from a talk by Prof Roderick Floud – 'Our Changing Bodies: The Lessons of Anthropometric History' – to be given at Gresham College, London EC1 at 6pm tomorrow; www.gresham.ac.uk