The researchers from Bristol University investigated children from the Oxford area between 1985 and 2004. By 2004 the incidence of diabetes in the under-fives had increased to one child in every 1,000.
Although the researchers identify that there is a genetic link, the rise is far too steep to be blamed purely on these factors. It is believed, therefore, that environment is having an effect.
Lead researcher, Professor Polly Bingley, suggests that individuals are being exposed to something new or we have reduced exposure to something that was previously controlling our immune responses. She believes that fewer mothers opting to breastfeed may be one factor.
Simon O'Neill, director of care at Diabetes UK, said: 'Whilst 10 to 14-year-olds remain the largest group for diagnosis, the rise in cases found in children under five is worrying'.