High Mercury Levels Linked to Type 2 Diabetes
Higher levels of mercury exposure in young adults have been linked to 65 percent increased risk of type 2 diabetes later in life.
The study was led by epidemiologist Ka He, chair of the Department of Epidemiology and Biostatistics at Indiana University School of Public Health. He is the first researcher to establish a link between mercury and diabetes.
The main source of mercury in humans comes from the consumption of fish and shellfish, which contain lean proteins and nutrients, such as omega-3 polyunsaturated fats and magnesium. These are important to a healthy diet, creating a complicated picture for researchers because they are also associated with increased mercury levels.
The study published in the journal Diabetes Care displayed a correlation between people with healthier lifestyles and increased mercury levels. These people exercised more, had a smaller waist circumference and lower body mass indexes (BMI) when compared to other participants in the study. They also ate more fish, which is often associated with a healthy diet and higher social economic status.
The research studied 3,875 men and women over an 18 year period as part of the Coronary Artery Risk Development in Young Adults. The study established the link between mercury levels and type 2 diabetes by monitoring participants with a controlled lifestyle and diet. Researchers also monitored levels of magnesium and omega-3 intake, which could counter the effects of mercury.
These findings stress the importance of avoiding fish with high mercury levels, such as sword fish and shark, and opting for fish with low mercury levels such as salmon, shrimp and catfish said He.
"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," He and the authors wrote in the study. "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."
The FDA and EPA guidelines also highlight suggestions for fish consumption, particularly for young children and women who are pregnant or of childbearing age.
Coauthors of "Mercury Exposure in Young Adulthood and Incidence of Diabetes Later in Life" include researchers from Northwestern University, University of Missouri-Columbia, Harry S. Truman Memorial Veterans Hospital, the National Heart, Lung and Blood Institute, and Johns Hopkins University.