People should have their cholesterol level checked from their mid-20s, according to researchers.
They say it is possible to use the reading to calculate the lifetime risk of heart disease and stroke.
The study, in The Lancet, is the most comprehensive yet to look at the long-term health risks of having too much “bad” cholesterol for decades.
They say the earlier people take action to reduce cholesterol through diet changes and medication, the better.
They analysed data from almost 400,000 people from 19 countries and found a strong link between bad-cholesterol levels and the risk of cardiovascular disease from early adulthood over the next 40 years or more.
They were able to estimate the probability of a heart attack or stroke for people aged 35 and over, according to their gender, bad-cholesterol level, age and risk factors such as smoking, diabetes, height and weight, and blood pressure.
Report co-author, Prof Stefan Blankenberg, from the University Heart Center, Hamburg, said: “The risk scores currently used in the clinic to decide whether a person should have lipid-lowering treatment only assess the risk of cardiovascular disease over 10 years and so may underestimate lifetime risk, particularly in young people.”
Up to eight million people in the UK take statins, which lower levels of bad cholesterol in the blood.
It is estimated one in every 50 people who takes the medication for five years will avoid a heart attack or stroke as a result.
An active lifestyle and a healthy diet can also reduce cholesterol.