When Does A Dog Become A Senior?

While your dog will always be a puppy at heart, one day they will become a senior dog. For most pet parents, that day seems to come all too soon, and it can be overwhelming to think about the changes that come with age.
In honor of Senior Pet Month, learn exactly what happens as dogs age, what to expect, and how to support your dog’s changing health needs. Armed with knowledge, you can be prepared for seniorhood and even look forward to spending time with your dog in their golden years.

Dog Years To Human Years
You may have once heard that a “human year” is equal to seven “dog years,” or that dogs age seven times as quickly as we do. So a year-old dog would be similar to a seven-year old child, and a ten year old dog would have aged similarly to a seventy-year-old human.
The truth is, the rate at which dogs age is a bit more complicated. Puppies mature rapidly during their first twelve months of life, nearly fully grown by their first birthday. After adulthood, aging slows down quite a bit.

Aging in Small Dogs vs Large Breeds
In general, the smaller the dog, the more slowly they will age. For example, the smallest popular breed, the Chihuahua, is considered fully grown by the time they’re a year old, and can easily live until their 20th birthday. The Saint Bernard, one of the largest breeds, is not an adult until they’re nearly 2 years old, but has a life expectancy of just 8 to 10 years.
With that in mind, at 10 years old, a Chihuahua will have aged similarly to a 45 year old human, but a Saint Bernard of the same age would actually be more biologically similar to an 85 year old.

What Age Does A Dog Become A Senior?
Remember that aging looks different for every dog, even those of the same size and breed. Lifestyle factors like diet, sun exposure, and body condition can all contribute to the rate at which a dog ages. Genetics, congenital defects, and acquired diseases, too, can affect aging.
According to the American Veterinary Medicine Association (AVMA), a dog is generally considered a senior by the time they are 7 years old. Large and giant breeds will hit their golden years a bit earlier around six years of age, while small breeds might not reach seniority until they’re closer to ten years old.

How Dogs Age
Your dog does not have to show noticeable signs of aging to be considered a senior. Some develop chronic health issues before middle age, and many dogs start to go gray around the muzzle as a young adult - while light-colored dogs never get that telltale silver face.
So, health and appearance are not reliable indicators of maturity. But there are some effects of aging that are inevitable and relatively similar between most dogs:

• Metabolism slows down and caloric needs may decrease, leading to weight gain
• Decline in immune system function, more susceptibility to disease
• Brain shrinks in volume, develops plaque buildup, and loses neurons, which can lead to canine cognitive dysfunction (CCD) or dog dementia
• Joint degeneration as the joint tissue wears down over time, leading to osteoarthritis
• Muscle loss as the muscles become less responsive to protein uptake and exercise
• Fewer, less-regular estrus cycles in unspayed females, though they do not go through “menopause” like humans. Uterine walls can become thicker with each heat cycle, increasing her risk of pyometra, a life-threatening uterine infection.

While it’s not possible to prevent the natural effects of aging, you can make lifestyle changes to help extend your dog’s healthy years.

Support for Senior Dogs
By the time your dog is around 7 years old, you can start to make lifestyle changes to support their changing health needs, even if you have not yet began to notice any signs of aging.

After 7 years old, make these changes to your dog’s lifestyle:

• Switch from yearly wellness visits to twice-yearly checkups
• Ask about senior blood panels and testing for diseases that commonly affect your breed, or as recommended by your veterinarian
• Consider switching to a senior dog food
• Supplement omega-3 fatty acids to support brain health, joint mobility, and heart health
• Work towards or maintain a healthy body weight by feeding fewer calories or a reduced calorie dog food, as recommended by your veterinarian
• Incorporate daily low-impact exercise like walking

The #1 most important thing you can do for your senior dog is make every moment count. Whether they still have many years ahead of them, or are expected to have a shorter lifespan, nothing extends their happy, healthy days quite like spending time with you.