HDL (high-density lipoprotein) cholesterol is supposed to control ‘bad’ LDL (low-density lipoprotein) cholesterol, which is blamed for causing plaques in artery walls, and which is linked to heart attacks and heart disease. Statin drug therapy is designed to help elevate levels of HDL cholesterol.
They made the surprising discovery when they analysed HDL levels in 1.7 million army veterans for a year, and discovered that those with both high and very low levels were more likely to die prematurely.
So why hasn’t this been seen before in earlier studies? Lead researcher Ziyad Al-Aly thinks it could be because the size of the groups in earlier trials had been too small to see the effects of HDL levels.