DEATH FROM DIABETES IN IRELAND/HISTORY.

Editor,

In your journal in 1987 Crawford reported on the history of deaths from diabetes in Ireland.1 His report showed that in the second half of the nineteenth century death rates associated with diabetes rose exponentially and he hypothesized that this was due to increases in the intake of carbohydrate and fat. For the last thirty years I have always opened my lectures on type 2 diabetes with this report. However, due to recent information from epidemiological studies of the consequences of famines, I believe that the original interpretation of this study is incorrect.

China’s Great Famine (1959-1961) showed that adults born between 1960 and 1961 had a 23% increased risk of developing diabetes and if born in a particularly affected area there was a 40% increase. This suggests that fetal exposure during the famine increased the risk of diabetes in adulthood.2

In the Ukraine Famine, individuals born between 1930 and 1939 had in 2001 an increased risk of developing diabetes. The prevalence of diabetes increased by 47% in those born in regions with severe famine compared with those born in areas where a famine did not occur.3

The Dutch Winter Famine occurred during the final six months of the second World War. 702 subjects born in Amsterdam between November 1, 1943 and February 20, 1947 were shown at age 50 to be more likely to have glucose intolerance and insulin resistance.4

The Irish Potato Famine began in 1845 and ended in 1852. From Crawford’s paper it can be seen that the greatest increase in death from diabetes occurred between 1880 and 1911 when those born during the famine would be between 30 and 60 years old.

The reason that starvation in utero is associated with a higher risk of type 2 diabetes in later life is that the fetus prepares for its likely adult environment which is not encountered (thrifty phenotype). These epigenetic changes are due to increased gene activity and expression rather than by starvation induced changes in the DNA sequence.5

Therefore, after 33 years, I believe it is time to reinterpret Crawford’s data and conclude that the large increases in death from diabetes during nineteenth century in Ireland was due to the in utero effects of starvation during the Irish Potato Famine and not due to increases in the intake of fat and sugar.