One Dog Year is Equivalent to 30 Human Years, New Study Reveals

Earlier, scientists believed that one dog year was equivalent to seven human years, the new finding has contradicted this belief

A pet looking at her owner
A female dog is looking at her two owners and listening to their instruction. Bhaswati/ IBTsg

Scientists have previously revealed that dogs usually age in a much different manner when compared to humans. They assumed that dogs age at seven times the rate of humans. However, a new study report has revealed that scientists have completely gone wrong in understanding the aging process of dogs. According to the study, a one-year-old puppy is actually about 30 in terms of human years.

Understanding The Epigenetic Changes

In the study at the University of California San Diego's school of medicine, researchers explain how they focused on epigenetic changes to DNA, in an attempt to understand the aging process of dogs.

Epigenetic changes are basically modifications that do not change the DNA sequence in the body but can toggle genes on or off. The team of experts looked at the way in which particular molecules called methyl groups get accumulated in areas of the human genome over time. They later compared them with how these molecules accumulated in areas of the dog genome.

The results were quite surprising, suggesting that every dog year is not equivalent to seven human years. In the first year, dogs usually age faster, and in the course of time, it slows down when compared with humans.

For example, a one-year-old labrador could have a human age of 30, but by the age of four, the dog's age will be equivalent to 54 human years.

Variance in Dog's Age

The research team revealed that these kinds of similar studies should be done on different breeds of dogs to understand the variance in their aging.

"For instance, the epigenome translated seven weeks in dogs to nine months in humans, corresponding to the infant stage when deciduous teeth erupt in both puppies and babies. In seniors, the expected lifespan of labrador retrievers, 12 years, correctly translated to the worldwide lifetime expectancy of humans, 70 years," wrote the researchers in their study report.

Lucy Asher, an expert in canine puberty at Newcastle University who was not a part of the research, welcomed the findings of the study.

"If we think about ageing in terms of how old our cells are, this new paper is really useful in matching up human and dog years. Whilst a 30-year-old human might have cells of an analogous 'age' to a one-year-old dog, many dogs won't be fully grown at this time and they will still have unsettled hormones and behavior associated with puberty," said Asher, The Guardian reports.