If you've been diligently working to raise your levels of "good cholesterol" to maintain a healthy heart, a study in the Lancet has some sobering news: You might be wasting your time. It's true that high levels of the cholesterol, called HDL, are associated with a lower risk of heart disease. But the study calls into question that all-important principle of "causal effect"—HDL itself may not be a cause of the lower risk, just a reflection of it, explains the New York Times.
“I’d say the HDL hypothesis is on the ropes right now,” a professor at the University of Texas Southwestern Medical Center tells the Times. The study could have a huge impact on the pharmaceutical industry, which is busy testing drugs designed to raise HDL. As for the so-called bad cholesterol, or LDL: The study makes clear that it's still good practice to lower LDL through drugs or lifestyle changes, notes the Daily Mail. (More HDL stories.)