Deaths from heart disease almost halved in the UK between 2005 and 2015, research has revealed.
The rate of people in the UK dying because of the world's number one killer dropped from 80 deaths per 100,000 people per year to 46.
Experts say quitting smoking has helped to slash the rate of the illness but soaring rates of obesity and type 2 diabetes threaten to undo that progress.
The study comes as another warning for Britons to slim down after the boss of the NHS last week warned cancers linked to obesity are expected to double by 2035.
Coronary heart disease is the leading cause of death around the world and rates have been falling in the majority of countries over the past 10 years as smoking rates drop. Left, the raw rates of people dying of heart disease in countries comparable to the UK and, right, the rates adjusted to look as if all people were the same age
Researchers from Imperial College London compared the UK's death rates over time and to those of other countries.
They found that, despite the drastic reduction in deaths from heart disease, it remains the most common cause of death in the country and worldwide.
'Much of the decline in heart disease deaths may be due to a fall in the number of people who smoke,' said Dr Alexandra Nowbar, a scientist at Imperial.
'However, obesity, blood pressure and rates of type 2 diabetes are on the rise, and if we don't keep tabs on these and encourage people to follow healthy lifestyles, we could see the trend of falling heart disease deaths reverse in the future.'
Almost two thirds (64 per cent) of people in the UK are overweight or obese, raising their risk of developing diabetes or heart disease, or having a stroke.
In comparison, fewer than one in six people (16.8 per cent) smoke cigarettes regularly – a drop from more than a quarter (27 per cent) in 2000.
Coronary heart disease is a deadly condition in which the blood vessels become blocked with fatty build-ups and reduce the ability of blood to flow round the body.
This can cause various life-threatening events such as a heart attack, stroke, or a pulmonary embolism if a blood clot travels into the lungs.
People who are overweight or obese are at higher risk of coronary heart disease and other potentially deadly conditions affecting the heart and blood vessels.
Fat is stored in many places in the body and the blood vessels – arteries and veins – are no exception. When it is broken down by the digestive system fat's converted into