TF and myocardial infarction: In another large study investigating the relation of NTBI, serum iron, transferrin saturation, and serum ferritin with the risk of coronary heart disease (CHD) and acute myocardial infarction (AMI), the results did not show an excess risk of CHD or AMI within the highest NTBI tertile when compared with the lowest, but rather seemed to demonstrate a decreased risk [27].