Dogs and health: A lower risk for heart disease-related death?

Are you a “dog person”? You know, one of those people who talks about their dogs all the time, shares photo after photo online (or, worse, in person), and considers their dog as a semi-human member of the family? (In the interest of full disclosure, I am a dog person.)

If you are, here’s a medical news story that may confirm what you’ve suspected all along. And if you aren’t a dog person, this may confirm your suspicion that researchers can prove just about anything they want. According to a recent study, your risk of having a cardiovascular event such as stroke or heart attack, and your risk of death, are lower if you have a dog. Some of the proposed explanations for this might surprise you.

Research finds a new connection between dogs and health

This new study reviewed the health and death records of more than 3 million people in Sweden ages 40 to 80 over more than a decade, and found that:

  • Compared with people in multi-person households without dogs, people living in multi-person households with dogs had a risk of death that was 11% lower, and risk of death due to a cardiovascular cause that was 15% lower.
  • These findings were even more dramatic for those living alone. Risk of death was 33% lower among dog owners, cardiovascular deaths were lower by 36%, and the risk of heart attack was 11% lower.
  • The benefit was greater for owners of certain breeds of dogs, such as retrievers and terriers.

Why might dog ownership come with health benefits?

The most obvious explanation for why dogs might provide their owners with certain health advantages is that dog owners tend to be more active. For many people, taking their dogs out of the house or apartment several times a day to “do their business” and walking their dogs is far more physical activity than their dogless neighbors. And this could explain why more active dog breeds (such as retrievers) are associated with the greatest benefit, and why single people (who must shoulder all of the “burden” of walking the dog) benefit the most.

But there are other potential explanations that researchers have considered, including:

  • Improved immune function. Believe it or not, having a dog that brings dirt and germs into the home could improve how the immune system functions and reduce harmful inflammation in the body.
  • Modifying the microbiome. The huge number of bacteria in our digestive tracts changes not only with changes in diet, but also with pet ownership. It’s possible that having a dog alters the types of bacteria we harbor, which in turn could affect inflammation in the body and resultant cardiovascular risk.
  • Social impact. Dog owners must, to at least some degree, focus outside themselves, which can promote social interaction. In addition, dog owners tend to bond with one another as their dogs play together and check each other out. Past research has found that social contact is linked with lower cardiovascular risk and rates of death.
  • Improved mood. Some have proposed that the unconditional affection and companionship of dogs can improve mood, and through this effect improve health.

Will getting a dog extend your life?

Not so fast. This study only found that dog owners tend to live longer and have fewer heart attacks than those without dogs. But that does not prove dog ownership itself it the reason. Maybe healthier, more active people get dogs more often than sedentary people, and it’s that self-selection that accounts for the observations of this latest research. It’s also possible that economic factors play an important role. Dog ownership can be expensive, and those who can most afford to own a dog might receive better healthcare, have better health insurance, or have healthier lifestyles. While the researchers tried to account for some of these possibilities, excluding some contribution from other “non-dog” factors is challenging.

We’ll need to have a better understanding of whether dog ownership itself truly provides health benefits and just how it works. Naturally, similar questions will arise regarding cats and other pets. Until we know more, the apparent health benefits of dog ownership should be encouraging to dog people everywhere. And if you aren’t a dog person, this latest research might convince you to become one.

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