Previous studies have suggested that the high saturated fat content of milk may contribute to cardiovascular disease. But Harvard School of Public Health researchers found that patients with higher levels of a type of conjugated linoleic acid (CLA), a type of omega-6 fatty acid found in milk, had a lower risk of MI.
Few previous studies have examined the link between milk intake and cardiovascular risk, but animal models have suggested that a common type of CLA called 9c.11t could protect against atherosclerosis, rather than contribute to it as expected. The protective effect may be due to beneficial effects on lipoprotein metabolism.
To test the association, researchers measured levels of the fatty acid in 1,813 nonfatal acute MI patients and 1,813 controls. They also analysed the association between dairy intake and risk of MI.
Individuals with raised levels of the fatty acid suffered fewer MIs. Dairy product intake did not raise the risk of MI, despite the high saturated fat content.
'It is possible that the potentially beneficial effect of CLA on MI offsets the adverse effects of saturated fat,' they said.