Genetically inherited high levels of cholesterol are twice as common as previously thought, new research suggests.
Previous estimates suggest that one in every 500 people suffer from familial hypercholesterolemia (FH) but a new study suggests that prevalence is actually around one in every 250 people.
FH is a genetic condition which results in high levels of cholesterol in the blood and increases a person's risk of having a heart attack or heart disease.
American researchers examined the data of 37,000 people to determine the number of probable and definite cases of FH.
Their study, published in the journal Circulation, found that men and women are affected equally.
"It's more common than we thought and it's important to look for it at a young age because someone with FH may have no symptoms until there is serious heart disease," said Dr Sarah de Ferranti, lead author of the study, who is assistant professor of paediatric cardiology at Harvard Medical School and director of preventive cardiology at Boston Children's Hospital in Massachusetts.
"A common story might be someone who develops chest pain or has a heart attack in their 30s or 40s - even though they look healthy, eat well, and are thin and fit."
The British Heart Foundation (BHF) said that as many as 250,000 people in the UK may have the inherited gene which causes FH but the charity estimates that as few as 20,000 people are receiving treatment for the condition.
Around 50,000 British children could be living with the potentially deadly gene which causes FH, but only 1 per cent of children have been identified, the charity said.
Dr Mike Knapton, associate medical director at the British Heart Foundation, said: "This study confirms that FH is far more prevalent than we first thought, yet worryingly the majority of people living with it have not been diagnosed.
"But thanks to our research it is now possible to have a DNA blood test to determine if you and your family have it."
