Pregnant women with higher blood levels of copper during their first trimester are more likely to have elevated glucose levels during their second trimester, according to the results of a new study.
Published in The Journal of Clinical Endocrinology & Metabolism, the study also found that blood levels of the trace metal molybdenum had the opposite effect — resulting in lower blood glucose levels during the second trimester of pregnancy.
Because blood levels of these metals are influenced by diet, the results of this study could have an impact on future dietary recommendations for pregnant women.
As noted in a Healio article on the study, researchers at the Harvard T.H. Chan School of Public Health looked at data from 1,857 healthy, normal-weight pregnant women collected between 2009 and 2013. They compared first-trimester blood levels of a number of metals — including zinc, selenium, copper and molybdenum — with blood glucose levels recorded in a second-trimester glucose challenge test.
The researchers found that for every 50% increase in blood copper levels, glucose levels rose by an average of 4.9 mg/dl. The risk of an abnormal result in the glucose challenge test also rose by 53%. These results stayed the same after adjusting for a number of demographic factors that the researchers thought might influence blood glucose levels.
On the other hand, every 50% increase in blood molybdenum levels was associated with an average blood glucose reduction of 1.2 mg/dl, and a 14% reduction in risk of having an abnormal result in the glucose challenge test.
The researchers noted that copper levels in pregnant women were higher, overall, than in a separate sample of women who weren’t pregnant — meaning that pregnancy might have some influence on copper levels. But further research could also confirm that reducing exposure to copper, such as in food, could reduce the risk of gestational diabetes.
A freelance health writer and editor based in Wisconsin, Phillips has a degree in government from Harvard University. He writes on a variety of topics, but is especially interested in the intersection of health and public policy.