We know you love your pet because he or she is cute, loyal, and entertaining, too. But scientific evidence suggests that you might want to show your pet some gratitude for your good health.

Pet ownership can boost your health and your social life, says Erika Friedmann, Ph.D., associate dean of research at the University of Maryland School of Nursing, who has conducted several studies on pets and well-being.

So today, on National Pet Day, here are three reasons to give Scruffy a little extra affection:

1. Pets Keep You Moving

Of all the research in the field, the strongest evidence suggests, unsurprisingly, that people with pets, especially dogs, tend to be more active than their pet-free counterparts.

“Exercising more is probably one of the best things that people can do in general,” says Evan Paul Cherniak, M.D., the lead author of a 2014 review of the benefits of pet ownership in the elderly, and director of the Geriatric Evaluation and Management unit at the University of Miami. “And because dog owners have to walk their dog, they’re forced to get outside and exercise.”

One study published in the Journal of Physical Activity and Health assessed the walking patterns of 41,514 adults living in California. They found that dog owners walked about 20 minutes more per week than people with cats, or those who had no pet.

An additional 20 minutes per week may not seem like a lot, but even modest increases in physical activity can be beneficial, according to the study authors, and can help you hit the Centers for Disease Control and Prevention recommendation of at least 2.5 hours of moderate-intensity physical activity (which includes brisk walking) per week.  

2. Pets Help Your Heart

According to the CDC, pet ownership is associated with decreases in blood pressure, cholesterol, and triglyceride levels—all factors that play a role in heart disease. Even after a heart attack, people with pets seem to do better. For example, in a study that followed 460 people aged 33 to 84 beginning six months after they had a heart attack, Friedmann and her colleagues from the University of Maryland School of Nursing found that pet owners were 67 percent less likely to die during the study period than those who did not have a pet.

“We think it’s the social support that may explain the benefits,” says Friedmann. Pets help reduce feelings of loneliness and depression, the latter of which has been linked to an increased risk of heart disease.  

3. Pets Ease Your Stress

Pet ownership, and animal therapy dog visits in particular, might boost mental health by counteracting anxiety and depression, says Friedmann, especially among the elderly.

One study published in 2013 in the the American Journal of Geriatric Psychiatry found that among 65 nursing home residents with moderate to severe dementia, those who participated in one 45-minute session of petting and grooming a therapy dog each week were less depressed and agitated over the two and a half months of the study than those who did not.

“There’s quite a bit of evidence showing that when a pet is present, people may be less stressed, and feel safer and more comfortable in the environments they’re in,” says Friedmann. For example, she says, walking with your dog in your neighborhood might make you feel safer than if you were walking alone. And there have even been studies that show that other people are more likely to be friendly—smiling at you, or striking up a conversation for example—when you’re accompanied by an animal.

Of course, not all pet owners will experience these benefits, say Friedmann and Cherniak, and pet ownership isn’t right for everyone. Caring for an animal can be expensive and require a lot of time, and pets could even pose a danger for the immune-compromised.

But for people who have the time, means, and desire to own a pet, there’s lots to love.