Lowering cholesterol levels should be thought about much earlier in life than previously thought, according to researchers.
It comes as a study found exposure to high or fluctuating cholesterol early in life may heighten the risk of developing a condition which can lead to heart disease and strokes.
Atherosclerosis is the narrowing of the arteries due to a build-up of fatty deposits. It can be caused by high cholesterol, as well as high blood pressure and smoking.
According to the NHS, people over the age of 65 are more likely to develop the condition.
However, a study led by scientists from the University of Cambridge and published in Nature, found the risk of atherosclerosisis can begin much earlier, with fluctuating cholesterol levels potentially increasing this risk.
Experimenting in mice, the team fed two groups a cholesterol-rich diet, either intermittently or continuously.
Ziad Mallat, a British Heart Foundation (BHF) professor of cardiovascular medicine at the University of Cambridge, said: “When I asked my group and a number of people who are experts in atherosclerosis, no one could tell me what the result would be.
“Some people thought it would make no difference, others thought it would change the risk.
“In fact, what we found was that an intermittent high fat diet starting while the mice were still young – one week on, a few weeks off, another week on, and so on – was the worst option in terms of atherosclerosis risk.”
Fluctuation may be dangerous due to how it impacts immune cells known as resident arterial macrophages, which alter in the early stages of atherosclerosis.
The study suggests intermittent high cholesterol may prevent these cells from becoming protective and can instead accelerate the disease.
Elsewhere, researchers analysed data from the Cardiovascular Risk in Young Finns Study, a long-term study tracking heart risks from childhood to adulthood.
More than 2,000 people recruited during the 1980s had ultrasounds of their carotid arteries when they were aged around 30 and again at around 50.
The team’s analysis found those who had been exposed to high cholesterol levels as children were more likely to have the biggest build-up of plaque in the arteries.
Prof Mallat added: “What this means is that we shouldn’t leave it until later in life before we start to look at our cholesterol levels.
“Atherosclerosis can potentially be prevented by lowering cholesterol levels, but we clearly need to start thinking about this much earlier on in life than we previously thought.”
Prof Bryan Williams, chief scientific and medical officer at the BHF, said: “Someone is admitted to hospital with a heart attack or stroke every three minutes in the UK. In most cases this is caused by atherosclerosis, the build-up of fatty material inside the arteries.
“This exciting new study, funded by the British Heart Foundation, provides new insights into the biological processes behind the development of blood vessel disease.
“Importantly, the study suggests that surges in cholesterol, not just consistently high levels, can cause changes in the blood vessels, priming them for the development of atherosclerosis.
“With this process starting early in life, these findings reinforce the importance of keeping cholesterol levels under control from an early age to better prevent heart disease and strokes later in life.”
