In the United States, one out of every two households includes a companion animal. As a pet owner, you know there's nothing like the feeling you get from being with your pet. Not only can she bring a smile to your face, but recent studies also show just how much your pet can positively affect your physical and mental health.

For years we’ve known that too much stress can make us sick. It weakens our immune systems and exacerbates existing health problems. Interestingly, pets can function as buffers against much of the daily stress we face.

A recent study by the American Heart Association found that therapeutic dogs lower anxiety, stress, and heart and lung pressure among heart failure patients. This was the first study of its kind in that it actually measured the patients’ physiological responses before, during, and after visits from a volunteer and a dog. The results were groundbreaking: Anxiety alone dropped an astounding 24 percent in patients who were visited by a volunteer and a therapy dog. This compared to a mere 10-percent drop in patients who were visited by a volunteer alone. No changed was noted in patients who received no visit.

Levels of epinephrine, a stress hormone, were also measured in this study. In this case, the drop was 17 percent for the patients with canine visitors, compared to a 2-percent drop in those with human visitors alone. Perhaps most noteworthy, though, were the results for the group without visitors: These patients’ levels actually rose about 7 percent.

With dogs in the study ranging from a golden retriever to a miniature schnauzer, the breed and size of the dogs seemed to be irrelevant. Although all dogs had to pass a behavior test to participate in the study – and patients were asked beforehand if they liked dogs and wanted to participate, the presence of the dogs is what made the biggest difference. Just being around a dog can be relaxing for many people, and apparently, it can also offer more tangible results.

Pet ownership has also been shown to reduce anxiety and hyperactivity. In fact, an earlier study found that watching fish swimming in an aquarium worked just as well as hypnosis in reducing anxiety in patients awaiting surger. Pets even appear to help after surgery by reducing recovery time.

And did you know that, as a pet owner, you have a reduced risk of high blood pressure and heart attack? A study by the Baker Medical Research Institute in Melbourne, Australia, found that pet owners had significantly lower blood pressure levels than non-pet owners.

Everybody knows that walking your dog is a great way to meet people. When accompanied by a dog, others see you as socially approachable and are more likely to start a conversation with you and share experiences. What pet owner doesn't like chatting about his animal companion's latest escapades?

How do we feel about our furry friends? According to the American Animal Hospital Association, pet owners consider their animal companions to be part of the family. Experts advise that if you do not have a pet, and can assume the responsibility, there's no better way to stay happy and healthy.

This article is provided by our friends at PetDoc, the nation's leading resource for pet care information.