Dogs are not only man's best friend, but also may be the key to living a longer life, a new study claims. Our four-legged friends have long been praised for their ability to help mental wellbeing, reducing anxiety and loneliness, but less has been reported about how they might have a positive effect on physical health.

Combining patient data of 3.8 million people from multiple studies, including England, researchers found owning a dog can lead to better cardiovascular outcomes, especially for heart attack and stroke survivors who live alone.

Scientists at the American Heart Association say that compared to those without a pet dog, owners experienced a 24 per cent reduced risk of all-cause mortality and are 65 per cent less likely to die after a heart attack.

Those who had suffered cardiovascular-related issues were also 31 per cent less likely to pass away.

The results support a separate study carried out by Sweden's Uppsala University, which showed a 33 per cent reduced risk of death for heart attack patients living alone after being released from hospital if they owned a dog.

A similar drop was seen among stroke patients once they were discharged, at 27 per cent lower than those without a dog.