New study debunks 'dog years' myth, dogs and humans age differently

The belief that a single year is the equivalent of seven years in "dog years," this ratio holds no weight whatsoever.

A puppy is shown looking up. Studies have shown that oxytocin levels spike when humans and their dogs gaze into each others' eyes (photo credit: Courtesy)
A puppy is shown looking up. Studies have shown that oxytocin levels spike when humans and their dogs gaze into each others' eyes
(photo credit: Courtesy)
A new scientific study debunks a widespread misconception on how dogs age.
While popular belief holds that a single year is the equivalent to seven years in "dog years," researchers at the University of California San Diego School of Medicine have found that this isn't true.
In fact, according to the study, published on Thursday in the journal Cell Systems, this 1:7 ratio holds no weight whatsoever, as dogs age at a completely different rate.
"This makes sense when you think about it – after all, a nine-month-old dog can have puppies, so we already knew that the 1:7 ratio wasn't an accurate measure of age," the study's lead author Prof. Trey Ideker explained in a statement.
This formula provides a new "epigenetic clock," which is a method to determine age in cells, tissues and organisms. It works by tracking molecular changes in DNA and changing methyl group patterns in the genome, with the studying focusing specifically on Labrador retrievers. Based on this calculation, a one-year-old dog is comparable to a 30-year-old human, while a four-year-old dog is comparable to a 52-year-old human. The rate of aging slows down when a dog reaches the age of seven.
Ideker and his team have experience studying epigenetic clocks, and have previously published such research regarding the epigenetic clocks for humans. However, these clocks were very limited, and may only be accurate for the specific individuals studied. These may not apply to other people, let alone entirely different species.
However, this new formula has the potential to be more applicable, due to having calculated the dogs' ages alongside humans and mice.
The study is somewhat limited, as the study focused on only one breed of dog, and other breeds are known to have longer lifespans. Further studies will need to study other breeds, but Ideker hypothesizes it will apply to all breeds.
The implications for this study are significant for vetrenarians, as determining their age can help treat canine patients. This is especially important, Ideker explained,as many veterinarians still use the 1:7 ratio model to help determine treatment.
However, the study is also significant for the field of anti-aging treatments.
“There are a lot of anti-aging products out there these days — with wildly varying degrees of scientific support,” Ideker said.
“But how do you know if a product will truly extend your life without waiting 40 years or so? What if you could instead measure your age-associated methylation patterns before, during and after the intervention to see if it’s doing anything?”
The lack of means to measure these variables before has been a road block for further advancement in this field. With a functional epigenetic clock, however, answering these questions could be closer than ever.