Summary

A meta-analysis conducted by The Department of Cardiothoracic Surgery at the Nanchang University in China found that there is a 27% increase in one's relative risk of developing coronary heart disease for every 1mg of heme iron consumed per day. To put this into perspective, the recommended daily allowance of iron ranges from 8-15mg per day. That means that somebody who is consuming only half of the RDA of iron could be increasing their relative risk of developing coronary heart disease by as much two-fold, assuming that the iron ingested was heme iron. So, somebody who is ingesting 8mg of heme iron per day could be increasing their relative risk of developing coronary heart disease by as much as 4x.

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