Conventional wisdom dictates that lowering ‘bad cholesterol’, known as Low-Density Lipoprotein or LDL is good for the heart.
However, scientists say raising levels of ‘good cholesterol’ known as HDL, may not protect you from cardiac disease because its higher concentrations have been associated with lower risk of heart attacks in some studies, but its exact mechanism has always been uncertain.
In the new research, scientists studied genes involved in raising HDL in about 170,000 individuals and found that 15 HDL raising genetic variants they tested do not reduce the risk of heart attack.
It was found that there was no difference in heart attack risk of individuals who carried genes involved in elevated HDL than those without the genetic variant.
A team of researchers from Harvard Medical school supports the research findings when it has found no direct link between raising good cholesterol levels, or HDL with a lower risk of a heart attack.
Dr. D. Prabhakaran, executive director, Center for Chronic Disease Control, said, ‘Heart attack is multifactorial and not confined to one single risk factor like low HDL.
‘While understanding genetics to develop new drugs may be useful, it would be wrong not to address other risk factors such as high blood pressure, high blood glucose, obesity and tobacco.’
The study published in the medical journal The Lancet compared heart-attack risk among people who inherited known genetic variants that gave them higher HDL levels.
This should mean they had a lower risk of coronary disease. However, the study of more than 50,000 people found no such link.
This implies that it is best to focus on lowering the levels of LDL in order to tackle heart disease.