Just quit smoking? This is how long it will take for your risks of major diseases to health drop back to normal

It could take more than two decades for the risk of heart disease to drop back down to average after an individual gives up smoking, a new study suggests.

For decades, experts have known that puffing on cigarettes can cause significant damage to the heart.

At least 15,000 heart disease deaths in the UK are attributed to smoking every year, according to the British Heart Foundation. 

Now, researchers in South Korea have discovered exactly how long it takes for an ex-smoker’s cardiovascular system to resemble a never-smoker’s: 25 years. 

What’s more, the findings revealed that heavy ex-smokers who’ve puffed for more than eight years have a similar risk of impending heart attack or stroke as those who still smoke. 

In the study, published in the journal JAMA, researchers examined health data from more than 100,000 ex-smokers and more than 4million never smokers. 

The ex-smokers were followed up a decade after they stopped smoking. 

Other details were noted including age, how old they were when they started smoking, how many cigarettes they smoked a day and their age when they quit.

The study found the link between smoking and cardiovascular disease risk was dose-dependent — meaning those who were light smokers saw their risk plummet relatively soon after stopping. 

But for heavy ex-smokers, who had smoked for at least eight years, the researchers concluded it could take 25 years for the risk of heart attack and stroke to reduce to that of someone who has never smoked.

The study authors said: ‘Heavy ex-smokers should be considered to have a cardiovascular disease risk equivalent to that of patients who continue to smoke.’

Smoking kills around 78,000 people in the UK every year, with many more living with illnesses due to their habit. 

Half of all smoking-related illness in the UK is cardiovascular, such as heart problems and stroke.

Dozens of studies have shown smoking is linked with heart failure — when the heart muscle does not pump blood around the body as well as it should, usually because it is too weak or stiff.

As a result, the heart cannot supply the body’s organs and tissues with the oxygen and vital nutrients it requires to work normally.

The 7,000 chemicals in tobacco — including tar and others — can damage blood vessels that supply the heart, which is thought to be behind some of the damage smoking inflicts on the organ.

Meanwhile, nicotine — a highly addictive toxin found in tobacco — is heavily linked with dangerous increases in heart rate and blood pressure.

Smoking also unleashes poisonous gases such as carbon monoxide into the body, which further reduces our oxygen supplies. 

Around one in eight Brits and Americans currently smoke, compared to nearly half of the adult population in the 1970s.