The American Heart Association says owning a pet may help to decrease a person's risk of suffering from heart disease and is linked with lower levels of obesity, blood pressure and cholesterol.

"Pet ownership, particularly dog ownership, is probably associated with a decreased risk of heart disease," said Houston professor Glenn N. Levine.

A study of more than 5,200 adults showed dog owners were more physically active than non-owners because they walk their pets. Other research has revealed the calming effects of pets, which are used in animal-assisted therapy programs.

Levine, the chairman of the committee that wrote the statement published online in the journal Circulation, added that the benefits are clear on cutting the risk factors for heart disease. But the studies are not definitive or prove that owning a pet directly causes a reduction in heart disease risk.

"What's less clear is whether the act of adopting or acquiring a pet could lead to a reduction in cardiovascular risk in those with pre-existing disease," he said.