Are you still multiplying your dog’s real age by seven to figure out how old they are in “human years?” Boy, do we have news for you.
Scientists have figured out a new, more accurate way to determine your dog’s human age. Let’s talk about this (earth shattering!) news.
Why 7 Years?
Where did the “multiply your dog’s age by 7!” thing get started, anyway? No one knows for sure, but most veterinarians agree it probably came out of estimation. The calculation appears to be based on a formula of an “average” dog’s lifespan being 10 years and the “average” human’s being 70. Neither, of course, are accurate.
The Epigenetic Clock
Only in the age of transparent DNA have scientists finally begun to understand what they now call the Epigenetic Clock. The clock isn’t a real clock, obviously, but is a measure of how a person’s (or dog’s) DNA changes as they age. Specifically, epigenetics looks at additions of methyl groups to specific DNA sequences. Lifestyle modifications, disease treatment, diet, exercise, and myriad other factors influence the rate of these methyl attachments.
Using more than 100 Labrador retrievers at various ages in a groundbreaking study, scientists determined that dogs and humans actually have very similar age-related methylation of certain genomes. This is particularly true for very old and very young dogs. This realization helped researchers determine a new, more accurate way to determine a dog’s “human age.”
The New Dog Age Formula
Prepare yourself: there’s a bit of math involved! The new formula is applicable to dog’s older than 1 year (the rate of ageing during a dog’s first year of life is significantly faster than during the rest of its life.)
16 ln(dog age) + 31
What on earth does that mean? Well, it’s the natural logarithm of your dog’s real age, multiplied by 16, plus 31.
But doesn’t that make your dog really, really old? Well, it depends! If you play around with the numbers a bit you’ll find that dogs age much, much faster at the beginning of their lives than we knew. A 2-year-old dog is actually more like 42 years old in human years! That rate of aging slows down drastically as they get older, though.
What Does it Mean?
The main takeaway here is that the first few years of your dog’s life are absolutely critical for setting a foundation of good health. Proper diet, exercise, and regular veterinary exams ensure your dog ages healthfully.
It also means you should be paying closer attention your dog’s health during the “middle” of their lives, from around ages 4-8 (or 53-64 in human years.) This period marks your dog’s golden years phase and is also when they can begin to show symptoms of highly treatable diseases such as diabetes, arthritis, and even depression.