The major sources of published anthropometric data on children are now over two decades old. Due to concern being expressed regarding the continued validity of such data, changes in the body sizes of the UK child population over the past three decades have been considered. Comparisons were also made between the size of the current UK child population to the current US child population, and to the most comprehensive source of measured data on US children (but which are now over 20 years old). The growth of children in the UK and US over the past three decades was assessed for an indication of secular growth trends. Stature increases were found to have generally been less than body weight increases (as a percentage) at 5th percentile, mean and 95th percentile levels for UK children, and UK children were found to be closer in size to US children now than they were 30 years ago.