FOOD FOR THOUGHT

DOGS AND HEART HEALTH
Dog owners know how much warmth and comfort their canine companions add to their lives. A growing body of research shows they can do more than that. The Harvard Medical School Health Report, Get Healthy, Get a Dog, discusses how having a dog can prompt you to be more active, help calm jagged nerves, and reduce feelings of isolation and loneliness. Just petting a dog can lower blood pressure and heart rate (while having a positive effect on the dog as well). A new Swedish epidemiological study in Scientific Reports finds it may cut your risk of death from cardiovascular disease.

Cardiovascular disease (CVD) is the leading cause of death worldwide, accounting for 45% of all deaths. Having diabetes means that you are more likely to develop heart disease and have a greater chance of a heart attack or a stroke. As well as a combination of healthy low GI eating, regular physical activity and appropriate medication (and quitting smoking, if you do), there’s a growing body of evidence suggesting having a dog can be good for your heart.

Swedish scientists, who used national registries of more than 3.4 million Swedes aged 40 to 80, found that dog ownership had a dramatic effect on people who live alone, cutting the risk of death from cardiovascular disease by 36%. In households with more people under the same roof, dogs had less of a positive impact, but still lowered deaths from heart disease by 15%. (Just over 13% of those in the study had dogs.) “If you have a dog you neutralise the effects of living alone” said Tove Fall, professor of epidemiology at Uppsala University.

The researchers analysed the effects of different breeds and found that owners of dogs originally bred for hunting, such as terriers, retrievers, and scent hounds, had the lowest risk of cardiovascular disease. People who buy hunting dogs may be more physically active in the first place, because the dogs require so much exercise. The relationship may work both ways though, with livelier dogs effectively demanding that their owners do not slip into an overly-sedentary lifestyle.

“These kinds of epidemiological studies look for associations in large populations but do not provide answers on whether and how dogs could protect from cardiovascular disease. We know that dog owners in general have a higher level of physical activity, which could be one explanation to the observed results. Other explanations include an increased well-being and social contacts or effects of the dog on the bacterial microbiome in the owner. My impression is that this has to do with social support,” said Fall. One key question is whether dogs protect humans against heart disease by reducing blood pressure or through some other effect.

“It may be that dog owners like to be outdoors more, or are more organised, or more empathic,” Fall said. “There might also be differences between owners and non-owners already before buying a dog, which could have influenced our results, such as those people choosing to get a dog tending to be more active and of better health.”

A recent article in The Conversation, Can pets create health in humans? says: “A study known as the “blue zone” study has focused on factors affecting longevity for over a decade. Nine factors have been identified as increasing lifespan in the communities studied, and many of these factors are increased by pets.” They include natural everyday movement, having a sense of purpose, regular destressing activities, belonging and commitment.

The bottom line from Harvard Health: Don’t add a dog to your life if you’re not ready or able to take care of one, and prepared to make sure it gets enough exercise. The potential benefits for your heart health are a plus.

Read more:

• Dog ownership and the risk of cardiovascular disease and death – a nationwide cohort study (Mwenya Mubanga, Liisa Byberg, Christoph Nowak, Agneta Egenvall, Patrik K Magnusson, Erik Ingelsson, and Tove Fall, Uppsala University) 
• Four ways having a pet increases your lifespan (The Conversation) 
• Get Healthy, Get a Dog (Harvard Medical School Health Report)