Cholesterol, a fatty substance mostly made by the liver and used by the body to build cells and produce hormones, has become a heart-health bogeyman. There are several types, but high levels of LDL (low-density lipoprotein) cholesterol increase the risk of heart attack and stroke. Often labelled “bad” cholesterol, LDL builds up over time on artery walls, narrowing them and restricting blood flow.
High LDL cholesterol is not confined to people who are overweight. “Genetics are the main driver of higher LDL cholesterol levels,” says Naveed Sattar, professor of cardiometabolic medicine at the University of Glasgow. “Diets have smaller effects and it’s not necessarily the total calories that count; it’s the amount of saturated fat.” (Found in cakes, biscuits, chocolate and many ultra-processed foods, saturated fat can raise LDL levels.) All of this means someone relatively lean can still have high cholesterol, either because of their genetic profile or dietary pattern.
