4. Improved Fitness.

A 2011 study published in the Journal of Physical Activity & Health revealed that dog owners were 34 percent more likely to complete the recommended minimum 150 minutes of exercise per week. Other research has shown that dog owners walk 19 more minutes a week on average, and that having a family dog increases physical activity among adolescents (a key finding as childhood obesity reaches epidemic proportions).

5. Greater Calm for Alzheimer's Patients

And for their families. Much of the burden of this disease (which afflicts one in eight people 65 and older) falls on patients' relatives, and I've seen it crush the spirit of even the most loving caretakers. But studies have revealed that Alzheimer's patients have fewer anxious outbursts if an animal is present, and research shows that caregivers can feel less burdened as well, especially if the animal is a cat (perhaps because cats require little additional care).

A study published in the Western Journal of Nursing Research found that even pet fish can help by facilitating healthy weight gain among Alzheimer's patients, who often suffer from a lack of adequate nutrition. In the presence of an aquarium, patients who paced tended to sit still longer, while patients who were typically lethargic became more attentive. Both effects led to better eating at mealtimes.

Not everybody can bring home a furry or aquatic friend, of course. But if life circumstances (like long hours or a persnickety landlord) keep you from owning a pet, you can still experience the health perks of animals by volunteering with rescues in dire need of affection. Go to to look up shelters near you.

Next: Dogs that provide extra support for people with special needs


Next Story