有人说养宠物对人类身心健康有好处，那么养狗真的可以让人健康长寿吗？据一项最近调查显示，狗主人患心血管疾病的可能性要远低于不养狗的人。这是为什么呢？这项调查的结果可信吗？

As a dog lover, our canine companions always fill me with joy. Whether pedigree or mongrel, tame or stray, whenever I see one, I smile. After all, their loyalty is indisputable, their companionship is always welcome, they fetch for us, guard for us and even work for us when required. Good old Fido has always been close to my, and many other's hearts.

Well, not content with just warming the cockles of your heart, it seems that our four-legged-friends actually lower the risk of cardiovascular disease, according to a 2017 scientific study, which looked at 3.4 million Swedes from 2001 to 2012.

The study concluded that this lower risk, which was particularly evident in owners of hunting breeds, may not just be due to the increased physical activity that goes hand-in-hand with owning a dog, but could also be down to dogs increasing the owner's social contact, or by changing the owner's bacterial microbiome, which is the collection of microscopic species that live in the gut. Dogs change the dirt in home environments and therefore expose people to bacteria that they would otherwise not encounter.

These effects were particularly marked in those who lived on their lonesome. According to Mwenya Mubanga of Uppsala University and lead author of the study, “single dog owners had a 33% reduction in risk of death and an 11% reduction in risk of cardiac arrest compared to single non-owners.”

However, before your heart skips a beat, Tove Fall, senior author of the study, also adds that there may be limitations. It's possible that the differences between owners and non-owners, which already existed before the dog was bought, could have influenced the results – or that people who are generally more active also tend to get a dog anyway.

It seems that the results are not as clear cut as they initially appear to be, but as far as I'm concerned, that's ok. I love dogs for how they make me feel and, cardiovascular benefits or not, they'll always be top dog to me – cross my heart.