You’re not going to believe this. The 7:1 Dog to Person Lifespan Ratio isn’t necessarily true. Despite scientific evidence to the contrary, this notion has reigned in popular imagination for over 50 years.  According to a recent article from The Wall Street Journal’s Carl “The Numbers Guy” Bialik, this simplified ratio for dog longevity is nothing more than the “7 Year Glitz”. For the full story, check out the full article at the link below.

For a few wowing highlights read on:


A Dog’s Life. Scientists estimate the average lifespan for dogs ranges between 8 and 16 years depending on the breed. Bigger breeds reach the development of an 18-year-old human in their first two years.


Living Longer. As more dogs are immunized and receive better veterinary care, few die young of distemper and parvovirus. So lifespan estimates from 30 years ago really aren’t accurate any more.


Consider the Source. Dog life expectancy data comes from pet-insurance companies, breed-club surveys and veterinary hospitals — three sources that can be biased. Since club members and people who invest in pet insurance are more likely to spend more on vet care, their dogs may live longer. And hospitals that admit the toughest cases may see shorter canine life spans.


No matter how you look at the numbers, they aren’t ever long enough. At least now that we know the 7:1 ratio is bunk, it’s okay to fudge your pup’s age. No one will ever know.


The Scoop:

The Wall Street Journal Article by Carl Bialik

The Author’s Blog

Dr. Kelly M. Cassidy’s Dog Longevity Site


Thank you to May for the photo.