According to scientists, the notion that one calendar year equals seven “dog years” is a misconception, as dogs age differently influenced by their breed and stage of life.
Instead of merely multiplying their dog’s age in “human years” by seven, pet owners could achieve a significantly more precise estimate of age by considering the dog’s size and maturity level.
Generally, smaller breeds tend to live longer than larger breeds, which means that, for instance, an adult chihuahua will age at a slower pace each calendar year compared to a great dane.
The complexity is heightened by the fact that smaller dogs also reach maturity faster than their larger counterparts, leading to quicker aging in the early stages of their life, according to experts.
As a result, after two calendar years, a smaller dog appears “older” than a larger dog; however, at the five-year mark, it seems “younger” in terms of its overall lifespan.
Dr. Kate Creevy, an assistant professor of internal medicine at the University of Georgia, noted that when considering the various aging rates at different life stages and a dog’s average life expectancy, the typical aging rate is roughly six years, not seven, for every human year.
However, this varies significantly between breeds. Bulldogs, which have an average lifespan of just six years, will age at a rate of about 13 years per calendar year, whereas longer-lived Miniature Dachshunds age only four years for the same period.
