The study was conducted by researchers at Indiana University School of Public Health who followed around 3,900 men and women between 20 and 32 years of age and who were free of diabetes in 1987. The researchers measured the mercury levels in their body by analyzing their toe nails and were tested for diabetes.
On following them up in 2005, the researchers found that those with highest levels of mercury had a 65 percent greater risk of developing type II diabetes compared to those with lower levels of mercury.
"It is likely that the overall health impact of fish consumption may reflect the interactions of nutrients and contaminants in fish. Thus, studying any of these nutrients and contaminants such as mercury should consider confounding from other components in fish. In the current study, the association between mercury exposure and diabetes incidence was substantially strengthened after controlling for intake of LCn-3PUFAs (omega-3) and magnesium", lead researcher Ka He said.