A recent study by psychologists from Miami and St. Louis Universities found that pet owners have greater self-esteem, are more physically fit, conscientious and extraverted and less lonely, fearful and preoccupied than non-owners. It appears that while some people spend a great deal of money on counseling or therapy, hoping for changes like these. Pets do it for free.

What stood out the most was the greater self-esteem and higher conscientiousness of the pet owners.

The study found no evidence that "pet people" tend to have poor relationships with other people or that their relationships with pets come at the expense of relationships with other people.

Most previous studies on the benefits of pets have looked at very specific groups of people, such as the elderly or HIV-positive men. This study looked at a much broader and representative group of people, not just those facing significant health problems.

The three-part study first looked at a 217-member community sample, 171 of whom were women, average age 31 and average income $77,000 a year. The focus was on finding if pet owners differed from non-owners on several measures of well-being. It found that overall, pet owners were happier, healthier and better adjusted than non-owners. What stood out the most was the greater self-esteem and higher conscientiousness of the pet owners.

The second part of the study surveyed a slightly older group of 56 dog owners about how their dogs improved their well-being and fulfilled their social needs. Fifty-one were women, average age 42, with an average income of $65,000 a year. It found that the support the pets provided to the owners complemented that from other people in their lives and didn't compete with it.

The third part of the study looked at a younger and less prosperous group of people: 97 college students who were asked to write about a time when they felt excluded or socially rejected. Then they were asked to either write a second essay about their favorite friend or favorite pet or to simply draw a map of the campus. When questioned about their feelings afterwards, writing about a pet helped overcome the feelings of negativity aroused by writing the first essay as well as writing about a friend did.

Taken together, the three parts of the study show several ways that pets improve the life and well-being of typical people. Unconditional love will do that.

An article on the study was published online by the Journal of Personality and Social Psychology on July 4, 2011. It will also appear in a future print issue of the journal.