Some people with high levels of supposedly "good" cholesterol are at much greater risk of heart disease, a study suggests.
The Telegraph reported that the new study from Cambridge University, published in the journal Science, has contradicted to earlier research that recommended HDL cholesterol as protection to the heart. The researchers found that some people with high levels of HDL cholesterol are at much greater risk of heart disease. The researchers have discovered that one-in-1,700 people suffer a mutation in a gene called SCARB1. But they also had an 80% increased risk of heart disease - that is roughly the same increased risk as for smoking.
Prof Adam Butterworth, one of the researchers from the University of Cambridge, told the BBC News website: "This is significant because we had always believed that good cholesterol is associated with a lower risk of heart disease.
"This is one of the first studies to show that some people that have high levels of 'good' cholesterol actually have a higher risk of heart disease so it challenges our conventional wisdom about whether 'good' cholesterol is protecting people from heart disease or not."
There have been huge efforts put into drugs to raise HDL in the hope they have the same impact as statins, which lower the bad cholesterol.
Prof Butterworth warned that drugs aimed simply at "trying to raise HDL may not be that useful".
According to Parent Herald, he also said that the size of different HDL particles or how good they are at transporting may be more important than the overall levels. And that may be a more productive avenue of research.
While the researchers have questioned the importance of boosting levels of HDL cholesterol, they insist it still remains a valuable tool for predicting the risk of a heart attack.
Although fellow researcher Dr Daniel Rader, from the University of Pennsylvania, added: "Eventually we may want to perform genetic testing in persons with high HDL to make sure they don't have mutations, like this one, that raise HDL but don't protect against, or may even increase, risk for heart disease."
Prof Peter Weissberg, the medical director at the British Heart Foundation, said: "This is an important study that sheds light on one of the major puzzles relating to cholesterol and heart disease.
