You've probably heard that having high levels of good cholesterol (or, high-density lipoprotein [HDL]) protects against heart attack and other disease. However, recent research published in the December 2008 issue of The FASEB Journal suggests that not all HDL is created equal - and, poor quality HDL may actually be bad for you .

Scientists from the University of Chicago reviewed previously published research on cholesterol and found that the HDL in people with chronic diseases such as diabetes and rheumatoid arthritis was different from the HDL in health people, even when the levels of HDL in the blood were similar. The scientists observed that, while good HDL reduces inflammation, dysfunctional HDL does not.

This research demonstrates that simply looking at cholesterol levels is not enough when predicting the risk for heart disease. It also helps to explain why people with 'normal' cholesterol levels still develop heart disease. The scientists emphasize that, beyond the quantity of good cholesterol, the quality of that cholesterol has more predictive power when determining heart disease risk.

Source

FASEB J. 2008. 22:4044-4054.