Research published today indicates that, by 2020, the number of adults aged over 45 with diagnosed and undiagnosed diabetes in Ireland is expected to rise to 9.1% of the population - or over 175,000 people.
The Institute of Public Health in Ireland conducted the research, in collaboration with University College Cork and Queen's University Belfast.
It was based on an analysis of the latest national health survey, Slán 2007.
Professor Ivan Perry of UCC said the rise in diabetes has the potential to overwhelm health services over the next decade.
He described as critical current Government proposals for increased taxation on sugar sweetened soft drinks.
Professor Perry said it was unfortunate that knowledge about the causes of obesity and diabetes did not change behaviour in relation to diet and physical activity.