HOW DOGS HELP US LEAD LONGER, HEALTHIER LIVES

Dogs seem to make us healthier than we would be without them. Social psychologist Bruce Headey conducted a survey of Australian dog-owners and found that they take fewer trips to the doctor and sleep better than non-dog-owners. They are also less likely to be on heart medications.

It’s not that dog-owners are naturally healthier; bringing a dog into your life somehow brings these benefits along. James Serpell, a professor of animal ethics at the University of Pennsylvania, conducted a study in the U.K. that followed pet owners through the 10 months after they adopted their pet. Among dog and cat owners, there was a significant reduction in minor health problems such as headaches, difficulty sleeping, indigestion and sinus trouble in the first month, and these changes lasted for the study’s duration. Their scores on measures of general health also improved, and dog-owners increased their physical activity considerably.

Some of the health benefits of living with a canine occur deep down inside us. No matter how tidy your home may be, there’s some dust in the air, on the floor and on surfaces. In a 2018 study by biostatistician Alexandra Sitarik and colleagues, researchers collected dust samples from 54 family homes—half of which had a dog and half of which didn’t—when the dog was initially brought into the home and a year later. By the one-year mark, the presence of a dog in the home was associated with “a higher percentage of variation in bacterial dust composition,” including traces of Moraxella, Porphyromonas, Capnocytophaga, Fusobacterium, Streptococcus, and Treponema bacteria.

This isn’t a bad thing. On the contrary, what’s come to be called the “Microbiota Hypothesis” suggests that dust from homes with dogs may influence the development and response of the human immune system by changing the composition of the gut microbiome in ways that reduce risk for allergies and asthma. A considerable body of research has found that young children who grow up with dogs in their households are less likely to develop allergies, eczema or asthma, which often occur together as part of what’s called the allergic triad.

The theory, according to allergists, is that early exposure to dog dander could induce a high-dose tolerance to allergens. By stimulating their immune system not to react to dog dander and other microbes carried by canines, growing up with a dog helps kids develop a greater tolerance for certain germs and airborne allergens, thus preventing potential allergies from developing.

Scientists believe this may be why kids raised with dogs have fewer allergies than those from pet-free homes. A 2018 paper by Bill Hesselmar of the University of Gothenburg in Sweden and colleagues examined data from more than 1,000 children, age 7 to 8, and found that among those who grew up without pets, 49% went on to develop allergies. The rate dropped to 43% for kids with one pet and 24% for those with three pets.

When it comes to pain, having a dog doesn’t make you impervious, but it can make the discomfort more bearable. This is partly because having a canine companion provides a continuous source of meaning, connection and support.

Research led by Mary Janevic of the University of Michigan School of Public Health examined how older adults with chronic pain felt their pets affected them. Participants reported that their dogs motivated them to get up and get moving, which helped alleviate their pain. The pets distracted people from their pain and generally improved their moods. As Janevic noted in an interview, “Engaging in pet care can give a sense of daily purpose and routine that keeps a person going, even when they are having a pain flare-up. In this way, pets can be thought of as a natural resource for chronic pain self-management.”

These findings were echoed in a 2020 study by April DuCasse and colleagues at Florida A&M University, which found that people with chronic pain reported that their pets improved their mood, sense of hope, activity levels, comfort and functionality. Besides having a positive impact on their human’s quality of life, the research found that canine companions provided some of the participants with “a reason to live and focus on the future” and “support that mitigates their suffering and enables them to live a more meaningful life.”

Research also suggests that having a dog is associated with lower blood pressure and cholesterol levels, a reduced risk of Type 2 diabetes and reduced physiological responses to stress. These effects may partly explain why dog ownership is associated with a 31% decreased risk of death from cardiovascular disease.

Across various age groups, multiple studies have found that our heart rate, blood pressure and stress levels tend to be lower when there’s a dog around. A 1995 study by health researcher Erika Friedmann and colleagues examined the impact of a dog’s presence when young people age 9 to 16 were asked to read aloud. The kids’ heart rate and blood pressure readings were lower when the dog was present, which the researchers interpreted to mean that it made the environment feel less threatening and more friendly.

The presence of other people doesn’t always have the same beneficial effects as the presence of pooches. In a 2002 study by social psychologist Karen Allen and colleagues, adults were placed in mentally and physically stressful situations. They were asked to perform mental arithmetic and endure a “cold pressor” test, in which their hand was immersed in ice water to induce a stress response.

The participants endured these tests alone, with their spouse or friend present, with their dog or cat present, or with both a human and an animal companion. In all of the scenarios, the people who had their pets present had lower baseline heart rates and blood-pressure levels. During the stressful situations, their blood-pressure and heart-rate increases were smaller, and they recovered faster, when their pets were present.

Of course, having a dog isn’t enough to prevent people from developing cardiovascular diseases. But when serious problems do arise, dogs can help us recover better. Research by Mary Herrald of New Mexico State University and colleagues found that among people who have heart attacks, those who have dogs are significantly more likely to complete cardiac rehab, which typically involves physical therapy and education about how to manage risk factors and avoid everyday sources of stress. What’s more, research by epidemiologist Mwenya Mubanga and colleagues found that people who have dogs survive longer after having heart attacks or ischemic strokes.

Besides having specific effects on health, your relationship with your dog may alter your attitude toward health and life in general. If you want to be around as long as possible to take care of your beloved canine companion, you may feel inspired to improve your lifestyle and stress-management habits. You may feel motivated to take better overall care of yourself, whether that means taking your medication as directed, exercising regularly or going to bed earlier. Even if you’re not inclined to do these things for your own well-being, you may do them for the sake of your beloved pooch.

Jen Golbeck is the founder of the social-media platform “The Golden Ratio” and Stacey Colino is a science writer. This essay is adapted from their new book, “The Purest Bond: Understanding the Human-Canine Connection,” published Nov. 14 by Atria Books.

2023-11-10T14:40:17Z dg43tfdfdgfd