Dog and cat owners have long known that a family pet can make life happier. Now, medical science is finding that pet owners also lead longer, healthier lives.

In fact, a growing body of published scientific research shows that having an animal companion - cats and dogs in particular -- improves both our emotional and physical well-being. These studies have connected pet ownership with favorable health effects ranging from lower blood pressure to reduced anxiety levels.

Good for body
Some of the studies show that owning a pet can have very real physical benefits for their owners. These include:

• Pet owners have lower blood pressure. It has long been known that the act of stroking a pet can reduce blood pressure. But a study at the State University of New York at Buffalo found that the beneficial effects continue even when the pet is not present. The study, which looked at a group of stockbrokers with hypertension, concluded that just owning a pet can help lower blood pressure -and keep it lower, even in stressful settings.

• Pet owners have lower blood cholesterol levels. A study of more than 5,400 people conducted by Australia's Baker Medical Research Institute found that pet owners had not only lower blood pressure, but also lower levels of blood cholesterol and triglycerides in comparison to the non-pet owners, reducing the risk of heart disease.

• Pet owners have a higher survival rate after serious illness. Two studies have found that heart attack patients who owned the pets were significantly more likely to be alive a year after they were discharged from the hospital than those who didn't. What's more, a study conducted at City Hospital in New York found that the presence of a pet affected survival rate even more than having a spouse or friends. Patients in hospitals or nursing homes who have regular visits from their pets have shown to be more receptive to treatment. The need to care for their pet gives them reason to recover and the will to live.

• Pet owners have fewer doctors' visits. Studies conducted by Cambridge University in England and at the University of California at Los Angeles have found that pet ownership corresponds to overall improved health and fewer medical care visits. A study of Medicare patients also found that seniors who own dogs go to the doctor less than those who do not. Even the most highly-stressed older dog owners in the study had 21 % fewer physician's visits than non-dog owners. And an Australian study of 6,000 households found that dog and cat owners required less medication for blood pressure, cholesterol, sleeping difficulties or heart problems.

And, for the mind
Anyone who has ever cared for a companion animal understands their role in emotional health. Pets offer unconditional love and attention; they make us laugh, help us relax and divert us from day-to-day concerns. Research has documented the psychological benefits of pet ownership:

• Pet ownership reduces loneliness. People who live alone find that having pets reduces feelings of loneliness. According to researchers, this occurs because the pet provides companionship, but also because the pet becomes a topic for conservation with other people, increasing social interactions. Pet therapy programs at nursing homes are credited with enabling patients to reach out beyond their own pain and isolation and start caring about the world around them again.

• Pet ownership fights depression. A study of AIDS patients conducted by UCLA, in 1999 found that pets provide a level of companionship that helped the patients cope with the stress of their illness. The study looked at more than 1,800 patients and found that those who did not have a pet were more than twice as likely to report symptoms of depression. And scientists in South Africa have conducted research that shows that a pet can serve as an anti-depressant, increasing the release of endorphins and other hormones tied to pleasure.

• Pet ownership helps us cope with stress. A study of breast cancer patients conducted at the University of Warwick in England found that pets can provide valuable support for women coping with cancer. Researchers found that in addition to tactile comfort, pets provided a relationship that, unlike many human relationships, was unaffected by the presence of a serious illness. The ASPCA is currently studying the value of the human-animal bond during times of tragedy, by investigating how family pets impacted people's lives during and after the events of September 11, 2001.

• Pet ownership aids childhood development. Studies have linked family ownership of a pet with high self-esteem in young children and greater cognitive development. In addition, children with pets at home score significantly higher on empathy and pro-social scales than non-pet owners.

• Pet owners enhance family life. Psychological studies have found that most pet owners view their pets as enhancing the quality of family life by minimizing tension between family members and by enhancing their owners' compassion for living things. One survey of U.S. families found that pets were of great importance during personal or family illness, death of friends and family members or a family crisis.

These studies only scratch the surface of the growing body of scientific research that has been conducted about the beneficial effects of animals on physical and mental health. For more information, visit the Delta Society's website at www.deltasociety.org, which provides an extensive selection of articles and scientific abstracts in the Health Benefits of Animals section of its website.

And, if you are thinking about adding a pet to your family, visit the ASPCA's website at www.aspca.org and check out their page of Adoption Tips.