Seven Years in Dog Years, Debunked
It feels like a cruel joke by nature: the short lifespan of dogs. We love them unconditionally knowing that there will come a day when we lose them. We’ll have to say goodbye as they run up ahead into the great beyond.
Because dogs grow old so much more rapidly than humans, we’ve always approximated their age by multiplying by seven. Now, new research is challenging the 7-year rule.
Scientists at the University of California San Diego School of Medicine discovered that the true secret to a canine’s age involves more than multiplying by a single number. And some of the news isn’t what we humans want to hear.
When dogs are young, specifically, scientists believe that they may age more rapidly than seven years to the single human year. This is truest during their first five years of life.
The researchers pointed out the reproduction abilities of dogs. Specifically, they’re able to have puppies when they’re only nine-months-old, which makes them much older than the person equivalent of five and a quarter years. Dogs are also full-grown by about 18 months, which is only 10 and a half in human years when using the “seven-year” rule. People tend to grow until they’re fifteen, sixteen, or older.
Even so, not all the news is bad: while dogs age faster when they’re younger, they don’t keep up this rate. Ultimately, the researchers concluded that a one-year-old dog is equivalent to a 31-year-old human. But that doesn’t mean a two-year-old dog is equivalent to a 62-year-old human. The process is not linear and, instead, slows as quickly as it begins.
Researchers think that a five-year-old dog is equivalent to a 57-year-old human and a ten-year-old dog is equivalent to a 68-year-old human, making the 7-to-1 ratio most accurate around the age of ten or eleven.
The researchers even came up with a way to calculate your dog’s age based on the type of device you’re using.
If using a Google calculator, for instance, multiply 16 by the natural logarithm function (this button appears as “ln”) and then input the dog’s age. Then add 31. A three-year-old dog, with this calculator, is 48 years in human years.
The reason science has called the 7-to-1 ratio into question is, in part, because no one’s sure where the ratio came from in the first place; it’s simply always been part of canine lore. The researchers also decided to look at aging dogs from a more scientific standpoint, focusing on the chemical markers of DNA and how they change with time.
The hope is that this novel discovery provides insight into the aging process of our fabulous, four-legged friends, perhaps even giving vets the highly desired power to reverse it.
JJ Keeler lives in Colorado with a house full of pets. She owns three dogs, two cats, and a hamster she bought as a bribe to get her daughter to ride the school bus. She has a BA in English Literature from the University of Colorado and has worked as a professional writer for fifteen years. Her clothes are perpetually covered in pet hair.
