To haem or not to haem

Consuming high levels of haem iron before pregnancy is significantly associated with increased risk of gestational diabetes, according to a prospective study of 13,475 women with a singleton pregnancy. 

During 10 years of follow-up, 867 women developed gestational diabetes. Those with greater levels of haem iron, most commonly found in red meat, had higher risk of gestational diabetes. 

Among smokers, the risk of gestational diabetes for those in the highest quintile for haem iron intake was four times higher than for those in the lowest quintile. The increased risk was 1.5 times higher among non-smokers. Total, non-haem and supplemental iron intake did not increase gestational diabetes risk. 

The researchers point out that most iron supplements contain non-haem iron.

Diabetes Care2011; 34:1557-63