From BBC News:
An international team found high levels of persistent organic pesticides (POPs) in the blood correlated to insulin resistance, a precursor to diabetes. POPs are stored in fatty tissues – the study suggested this may be why obese people are more vulnerable to diabetes. However, experts have said that the study published in Diabetes Care is far from conclusive.
Patients resistant to the hormone insulin are unable to remove excess glucose from their blood, and this is normally an important step in the onset of type two diabetes. The new research therefore suggests that POPs act critically at a very early stage in the development of diabetes. In 2005 researchers in Sweden found people exposed to high levels of POPs were more at risk of developing type two diabetes. They found higher levels of POP residues were present blood samples of men and women who had diabetes than in those who did not. The authors of the current research, based at Kyungpook National University and the University of Minnesota, also previously found blood concentrations of POPs were linked to the prevalence of diabetes.
Obese patients with low POP levels had an unexpectedly low incidence of diabetes.
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