They Studied 80 Lab Retrievers for 12 Years, and This Is What They Found

Analysis by Dr. Karen Shaw Becker

senior dog food

Story at-a-glance -

  • Recent research confirms older dogs can experience detrimental physiological changes just as aging human bodies do, including oxidative damage and increased inflammation
  • To help combat the effects of aging, it’s important to offer the right diet; the perfect fuel for most dogs, especially older ones, is a variety of living, whole foods suitable for a carnivore
  • An antioxidant-rich diet will help reduce oxidative stress and DNA damage, and play an important role in your dog’s longevity
  • Most older dogs can also benefit from joint support, brain health and digestive health supplements, as well as supplemental omega-3 fatty acids

Recently, researchers affiliated with and funded by pet food manufacturer Mars Petcare published a study that looked at how inflammation, immune responses and other factors change as dogs age.1

The study involved 80 Labrador Retrievers who were evaluated from adulthood, starting in 2003 or 2005, to death or old age in 2015 and 2016. Throughout the study, the researchers measured levels of certain chemicals in the dogs' blood, and observed the following changes as the dogs aged:

  • 51 percent increase in DNA damage, specifically, increased 8-Hydroxydeoxyguanosine (80HDG) levels; 80HDG is a specific marker of oxidative damage to DNA
  • 30 percent increase in C-reactive protein (CRP), which rises in response to inflammation
  • 86 percent decrease in Heat Shock Proteins (HSP70), which measure the ability of the body to repair cellular damage

These results illustrate that just like humans, dogs' bodies experience damaging physiological changes as they grow older. The pet food company-affiliated researchers conducted their study with an eye toward developing formulas they can market to pet parents with older dogs. Needless to say, I'm no more a fan of add-ins to processed pet food than I am of processed pet food. No amount of supplementation can undo the deleterious effects of a poor-quality diet.

Highly processed pet feed (most pet food isn't made from human-grade ingredients and is therefore, by definition, animal feed) does not nourish aging bodies in a way that slows degeneration. In fact, looking at food choices (fresh, canned and dry food) and the levels of advanced glycation end products (AGEs) in these foods (which can dramatically affect the aging process) is what the nonprofit organization CANWI is raising money to research.

It's also important to note that AAFCO (Association of American Feed Control Officials) hasn't established nutrient profiles for senior or geriatric pets. This means processed pet food diets with added supplements marketed for older dogs are formulated without guidance from AAFCO.

With that said, I think it's tremendously beneficial to add appropriate high-quality supplements to an older dog's excellent-quality, nutritionally balanced, fresh food diet. These can include antioxidants to combat oxidative stress, joint support supplements, nutraceuticals for brain health and others depending on your dog's individual needs.

I almost always recommend digestive enzymes and probiotics for older pets. For dogs who need additional fiber, I suggest supplementing meals with natural sources of fiber such as psyllium husk powder, ground dark green leafy vegetables, coconut fiber or canned 100 percent pumpkin.

I also typically recommend an omega-3 fatty acid supplement such as krill oil (my favorite), another fish body oil (but not cod liver oil) or algal DHA for pets who are allergic to seafood.

First Things First: Feed Your Older Dog for Optimal Health

Contrary to what many pet parents and even veterinarians believe, aging pets need more protein than their younger counterparts, and the quality is of paramount importance. The more digestible and assimilable the protein is, and the higher the moisture content of the food, the easier it will be for aging organs to process.

Feed a nutritionally balanced, species-appropriate diet rich in healthy fats, including omega-3 fatty acids such as krill oil. The perfect fuel for an aging dog is a variety of living, whole foods suitable for a carnivore.

Eliminate all refined carbohydrates, which are just unnecessary sugar. No grains, potatoes or legumes, which foster inflammation in the body. Replace those unnecessary carbs with extra high-quality protein. Eliminate extruded diets (kibble) to avoid the toxic byproducts of the manufacturing process.

Most pet foods are manufactured in a way that creates byproducts that can affect cognitive health, including heterocyclic amines and acrylamides, in addition to AGEs. Fresh, biologically appropriate foods provide the whole food nutrients and amino acids an aging brain requires.

The right diet will also enhance your dog's microbiome, which has been linked to improved cognitive health in humans, and I've seen an improvement in pets as well.

Antioxidants Provide Longevity Benefits

Antioxidants are molecules that gobble up toxic free radicals floating around in your pet's body before they can harm healthy cells and tissue, thereby reducing oxidative stress and DNA damage. Antioxidants play a key role in longevity, and several studies of older dogs have proved the benefits of an antioxidant-rich diet for the aging canine brain.2,3,4,5 The more free radicals the body makes, the more antioxidants the body requires.

Most commercially available pet foods, even those of very high quality, contain synthetic vitamins and minerals that provide minimal nutrition, not optimum nutrition. Your dog's body is designed to absorb nutrients from fresh, living foods very efficiently. Antioxidants are contained in the vitamins in fresh foods, including:

  • Vitamin A and carotenoids, which are found in bright colored fruits and veggies like apricots, broccoli, cantaloupe, carrots, peaches, squash, sweet potatoes and tomatoes
  • Vitamin C, found in citrus fruits and strawberries, as well as green peppers, broccoli and green leafy vegetables
  • Vitamin E, found in nuts and seeds
  • Selenium, found in protein sources like fish, chicken, beef and eggs, as well as Brazil nuts

Phytochemicals also contain antioxidant properties:

  • Flavonoids/polyphenols are in berries and tea (decaffeinated and cooled, for pets)
  • Lycopene is in tomatoes and watermelon

Lutein sources are dark green vegetables like spinach, broccoli and kale

Supplements for Aging Joints

Keeping your dog at a healthy weight and physically active will help control arthritis and degenerative joint disease as he ages. Chiropractic adjustments, water exercises and acupuncture can also provide enormous benefits in keeping dogs mobile in their golden years.

There are a wide range of supplements that can be added to your dog's diet to help maintain healthy tendons, ligaments, joints and cartilage. These include:

  • Glucosamine sulfate with MSM and eggshell membrane
  • Omega-3 fats (krill oil)
  • Ubiquinol
  • Supergreen foods like spirulina and astaxanthin
  • Natural anti-inflammatory formulas (curcumin, proteolytic enzymes and nutraceuticals)

Supplements for Brain Health

Nutraceuticals can significantly improve memory, and the effects are long-lasting. Krill oil and other healthy fats, including MCT oil, are very important for cognitive health. Studies of medium-chain triglycerides (MCTs) such as coconut oil show they can significantly improve cognitive function in older pets.

MCTs provide an alternative energy source for the brain in the form of ketone bodies versus glucose, which can dramatically improve brain metabolism and cellular energy within the central nervous system. Supplementing with MCTs is a great way to offer an instant fuel source for your dog's brain.

Ketone bodies cross the blood brain barrier to efficiently nourish aging brains. I recommend 1/4 teaspoon per every 10 pounds of your pet's body weight, added daily to his food. Your pet's brain is about 60 percent fat, and that fat needs to be appropriately fueled as he ages.

I also recommend providing a source of SAMe (S-adenosylmethionine). Other supplements to consider are SOD (superoxide dismutase) and resveratrol, which is Japanese knotweed. Japanese knotweed has been proven to help reduce free radical damage and beta-amyloid deposits.

Ginkgo biloba may improve blood flow to the brain. Phosphatidylserine and ubiquinol, which is the reduced form of CoQ10, feeds your pet's mitochondria and improves cellular energy.