Image copyright Getty Images Image caption In September alone, an estimated 7,400 people will die in England from heart disease or stroke

One-tenth of 50-year-old men have a heart age 10 years older than they are, heightening their risk of a fatal heart attack or stroke, a study suggests.

The Public Health England analysis is based on responses from 1.2 million people to its Heart Age Test - 33,000 of whom were men aged 50.

The organisation also predicts that 7,400 people will die from heart disease or stroke this month alone.

Heart disease is the main cause of death among men and second among women.

Most of these deaths are preventable and a quarter are people aged under 75.

"Addressing our risk of heart disease and stroke should not be left until we are older," PHE's head of cardiovascular disease Jamie Waterall said.

How to improve your heart health:

Give up smoking

Get active

Manage your weight

Eat more fibre

Cut down on saturated fat

Get your five a day fruit and vegetables

Cut down on salt

Eat fish

Drink less alcohol

Read labels on food and drink packaging

Source: NHS Choices

PHE said about half of the survey respondents did not know their blood pressure and that 5.6 million people living in England currently have high blood pressure without knowing it.

This is "extremely worrying", according to Dr Mike Knapton of the British Heart Foundation.

"These silent conditions can lead to a deadly heart attack or stroke if untreated," he said.

A new version of the test on the BHF website refers users to apps and other resources to help them get their blood tested and improve their heart health.

Getting your blood pressure tested "can be the first important step to prolonging your life", said Katherine Jenner of Blood Pressure UK.