We’ve heard it all before: There’s “good” cholesterol, called high-density lipoprotein (HDL), that provides protective benefits against heart attacks and then there’s “bad” LDL cholesterol, which raises risk for heart problems in high levels.

A new study finds that HDL cholesterol might not boost your heart health as doctors once thought.

The study looked at the genes of about 170,000 individuals, looking for variations in DNA that earlier research shows naturally raise HDL levels in those who possess them. After looking for these 15 genetic variations – called single nucleotide polymorphisms (SNPs) – in the participants, the researchers discovered none of these variations actually reduced their risks for having a heart attack, compared with people who didn’t have the variations. . .