Can Grey Hair Be A Sign Of Stress in Dogs?


Many of us have heard of the stories about the fate of Mary Antoinette, the French Queen who’s hair allegedly turned white the night before she was due to be beheaded. Or, perhaps, Sir Thomas More who’s hair similarly turned white overnight before his execution by King Henry VIII. But, is this really true and, if so, can it happen with other animals too? Read our Holidays4Dogs article to find out whether grey hair can be a sign of stress in dogs.

Scientists insist, accounts of such rapid hair whitening are more likely to be the work of fiction, rather than fact. However, there is some evidence to suggest that high levels of continuous stress, over long periods, can impact on the process of greying hair. Furthermore, this can happen with dogs as well as people.

Natural greying.

Just as in people, there tends to be some variation in the timing of when hair turns grey in dogs.

Generally speaking, this becomes noticeable when a dog gets to about 7, or 8 years of age in small to medium dogs. In large breeds, this may be more noticeable when the dog reaches around five years of age.

There is no definitive answer as to why hair becomes grey. However, one theory is that the process of aging wears down DNA.

As a result, this inhibits the production of melanocytes – the cells that produce melanin. Melanin is a pigment present in every hair follicle and which produces hair colour.

Some breeds of dog are also more prone to premature greying and these are often dogs that tend to shed more throughout their lives. Black and grey dogs will often show more marked signs of going grey, as grey hairs show up more than they do on lighter coloured dogs.

Health issues.

Greying hair can sometimes be associated with certain health conditions. Often these are associated with liver and kidney function, but one of the most common underlying health conditions is hypothyroidism. If your dog seems to be developing grey hair prematurely, it is always wise to get him, or her, checked out with your veterinarian.

Stress factors.

In 2011, a scientific team discovered that stress can have an effect on greying of hair, causing premature loss of pigment in people. More recent studies have found that similar stress factors can have an impact on greying of hair in dogs too.

A recent new study carried out in Colorado and published in the Applied Animal Behaviour and Science journal looked into the phenomenon in dogs. The results showed that greying of the face and muzzle, was not necessarily just a sign of old age.

The study included 400 dogs of various different breeds aged from one to four years. It did not include dogs with light coloured coats, as the distinction between grey hair and pale coloured hair was more difficult to distinguish.

Surprisingly, female dogs tended to show more marked greying of hair than male dogs. The researchers found that there was a relationship between owner-reported anxiety and impulsivity and premature greying of the dog’s muzzle.


Most of the time, grey hair on dogs is just a sign of ageing. The same as it is in humans and other animals. As dogs age much more quickly than we do, you are likely to notice your dog getting grey faster.  If you are concerned about any aspect of your pet’s health – always seek advice from a qualified veterinary practitioner.