Millions of Britons are risking heart attacks and strokes because unhealthy lifestyles are causing their hearts to age prematurely.
The obesity crisis is taking its toll on the nation’s heart health with 78 per cent of over-30s found to have hearts that are older than they should be.
And 14 per cent have hearts that are a decade older than their actual age, according to analysis of tests taken by 1.9million people.
Experts warned that the findings show poor diet and a lack of exercise is putting millions at greater risk of potentially fatal heart problems in middle age.
Simon Gillespie, chief executive of the British Heart Foundation, said: ‘Millions of people in the UK are unknowingly living at high risk of a heart attack or stroke due to their lifestyle, their family history of heart disease, or undiagnosed conditions including high blood pressure and cholesterol.
‘Our message today is that it’s never too late to change. Take the test, and if you are concerned by the age of your heart, make an appointment to see your GP.’
Researchers from Public Health England used an online test which questions people about their weight, height and lifestyle.
Since its launch three years ago, 1.9million people have taken the heart age test, with 34 per cent recording a heart age that is five years higher than their actual age.
Having a high heart age is a marker that someone is at increased risk of dementia, heart attacks, strokes, chronic kidney disease and diabetes.
But in many cases the risk can be reduced by taking more exercise, adopting a healthier diet and cutting back on alcohol intake, officials say.
Researchers found the risk was highest among men, with 81 per cent of those who took the test found to have a heart age older than their chronological age, compared with 74 per cent of women.
Around one in six men – 16 per cent – had a heart age that was ten years older than a healthy person’s their age, compared with one in ten women.
The gap increased with age, with only 2 per cent of men and 1 per cent of women in their 30s showing a ten-year gap between real age and heart age.
This increased to 6 per cent of men and 7 per cent of women in their 40s, 17 per cent of men and 13 per cent of women in their 50s, and 31 per cent of men and 19 per cent of women in their 60s.
Among those in their 70s, 42 per cent of men and 33 per cent of women had a heart age a decade older than it should be.
The results show that by age 40 both men and women typically had a heart age of 43, while by 65 the average heart age for women was 70.3 and for men 72.4.
In England, 84,100 people die from a heart attack or stroke each year. One in four of these are among under 75s, of which up to 50 a day are potentially preventable.