Medical science is now proving what animal lovers have long known: having a companion pet improves your overall health – and can even save your life. This is the conclusion from a growing number of studies.

Research scientist Peggy McCardle cites “mounting evidence that dogs, cats and other companion animals such as horses can promote psychological and physical health benefits in their owners.” Studies in this area go back for at least thirty years; for example, in 2009, U.K.-based Mars Inc., a pet food and health products company, sponsored a major study to examine human-animal relationships and interactions and their effect on physiological health and psychological development.

A 2008 book by journalist and equestrian Karin Winegar, titled Saved: Rescued Animals and the Lives They Transform, chronicled a number of cases in which companion animals have literally saved a human’s life. Winegar says, “We’ve seen this from coast to coast, whether it’s disabled children at a riding center in California or a nursing home in Minnesota, where a woman with Alzheimer’s could not recognize her husband but she could recognize their beloved dog.” Other studies have shown that autistic children will often respond to a pet when they cannot or will not relate to other people.

The most recent study was published in Scientific Reports. Results showed a significantly reduced risk for heart disease among dog owners – in some cases, of up to 36 percent. This is especially important for people living alone as opposed to those with families or other social support group. Mwenya Mubanga, a co-author of the study, noted that “dog ownership was especially prominent as a protective factor in persons living alone, which is a group reported previously to be at higher risk of cardiovascular disease and death than those living in a multi-person household.” A dog can even sense when its diabetic owner is experiencing a dangerous drop in glucose levels.

The study, carried out at Uppsala University in Sweden, examined records of more than 3.4 million subjects over the course of a dozen years, all between age 40 and 80. Lead author Tove Fall says that “dog owners in general have a higher level of physical activity, which could be one explanation to the observed results.” Findings also indicate that greater social well-being and positive effects on the immune system (the latter possibly due to dogs licking their owners and bringing dirt into the home) also figure into the equation.

So…what sort of breed is the best for protecting and improving one’s overall health? Not surprisingly, those who experienced the greatest cardiovascular benefits were the owners of physically active breeds, such as hunting dogs, terriers and retrievers. However, Fall says that living with most any breed will have some positive effect on heart health.

When it comes to psychological health, Winegar has additional insight: “The human-animal bond bypasses the intellect and goes straight to the heart and emotions and nurtures us in ways that nothing else can,” she says.

Again, this is something of which most anyone who has ever owned and loved a dog is well aware. Animals do not judge or condemn. Factors such as physical appearance, choice of partners, religious/spiritual beliefs, or political inclinations are meaningless to companion pets. All they ever ask in return is food and a bit of kindness.

Best of all, there are no dangerous side effects. It is something to consider the next time you run across a stray puppy who looks to be in need of a home.