7 Ways to Boost Your Dog’s Immune System

Your dog's immune system is their defense system against damaged cells and external invaders such as bacteria and viruses. However, an immune system is easily weakened, often without a pet parent knowing. Pollutants, diet, and an unhealthy mental state can affect your dog's ability to battle disease.

There are all sorts of dog immune system boosters and supplements for dogs available on the market. But as pet parents, we need to address the immune system holistically. On their own, supplements mean little without complete care of our dog's minds and bodies.

natural ways to boost your dog's immune system
Keep your dog’s immune system in shape through lifelong preventative care

But what affects your dog's immune system, and what can help strengthen it?

How your dog's immune system works

Essentially, there are three main lines of defense in your dog's body:


The first defense is the physical barrier between their inner body and the outside world. This includes the skin, the cornea of the eye, and the digestive and respiratory tract, and injuries can lead to infections. But changes in their microbiomes are just as dangerous.

The skin, gut, and even the lungs have a natural mix of "good" bacteria, fungi, and other microbes that keep each part functioning correctly. But a weak immune system can disrupt your dog's natural microbiome.

For example, a healthy immune system will keep invisible mites called demodectic mange in check and harmless. But, a weakened immune system will let them spread, causing the dog to lose hair around their face and even their entire bodies.

Nonspecific Immunity

The second line of defense is nonspecific immunity. These are the white blood cells that gather to travel around the body, removing damaged cells and antigens. It doesn't discriminate and pretty much attacks anything it recognizes as foreign, from pollen to bacteria and viruses.

Nonspecific immunity needs acute inflammation to work. Through inflammation, the body can dilate blood vessels and send white blood cells to damaged tissues or attack antigens.

But when acute inflammation becomes chronic, it can begin to damage cells and cripple the dog's ability to fight off disease.

Inflammation can also get out of control and cause serious health issues such as arthritis, skin inflammation, or enteritis.

Specific Immunity

Finally, you have the specific immune system which your dog is not born with. As your puppy is exposed to different antigens, the cells develop a memory for the best way to defeat it. It is specific because it learns particular ways to target foreign invaders they have previously encountered.

Vaccines make use of the specific immune system by introducing neutralized forms of viruses such as parvo to your puppy's immune system. This way, the immune system can learn how to attack the actual virus if it encounters it.

So how can you strengthen your dog’s immune system naturally?

1. Diet and your dog's immune system

a dog eating a balanced raw diet to boost the dog's immune system
To ensure that your dog’s immune system is healthy, pay special attention to their diet

An excellent canine immune system starts with a healthy, diverse, and species-appropriate diet. In fact, the gut accounts for 70% of a dog's first line of defense against disease.

Dogs need a healthy balance of protein, carbohydrates, good fats, vitamins, and minerals to stay healthy and feed their microbiome.

Usually, a good diet should provide everything a dog or cat needs to keep them healthy. It's far more beneficial to invest in a high-quality diet with no supplements than to give a bad-quality, over-processed diet with many accessories.

You can use Pet Assistants Food Finder and Food Comparison tools to look for the most nutritious food on the market or check your current food scores against food with nearly identical ingredients.

A diet rich in human-grade animal protein, whole grains, and whole vegetables should provide necessary vitamins and minerals in their most bioavailable form. Naturally available antioxidants help destroy free radicals and reduce inflammation. At the same time, the right amount of fiber can keep the gut biome healthy and working.

The wrong food can also compromise your dog's immune system. Even so-called "premium" or "prescription" brands can be misleading on this front. Some dietary factors to watch out for include:


Some foods actively work against the immune system. While salt is necessary for dogs, there is usually enough of it naturally available in fresh foods. Too much salt can trigger inflammation and potentially increases the chances of an autoimmune disease.

An incorrect balance of omega-6 and omega-3 Fatty acids

Omega-6s are vital for inflammatory responses when they are needed. Remember, an appropriate inflammatory response is key to a functioning immune response.

At the same time, omega-3s are necessary to stop inflammation when it has served its purpose. Both are essential to your dog's healthy immune system.

Ideally, a dog should have a ratio of 5:1 in favor of omega-6 fatty acids to balance necessary inflammation and inflammation reduction when the threat has been dealt with.

A properly formulated fresh, freeze, or dehydrated diet should have the proper fatty acids ratio. Suppose you are feeding your homemade dog food. In that case, you can try a readymade premix that is already correctly balanced for peace of mind.

Processed and charred meats

Highly processed or burnt meat is high in advanced glycation end products (AGEs), contributing to chronic inflammation and disease. This is one reason that feeding fresh meat is better.

Commercial pet foods process their animal proteins with extreme heat through rendering and extrusion, which leads to the denaturing process and Maillard Effect, of which a by-product is AGEs.

Likewise, the starch used as a binding agent in commercial pet food is also scorched, leading to more free radicals and carcinogens in your dog's food. Too much of both, fed over the years, can eventually overwhelm your dog's natural defenses.

2. Supplements for your dog’s immune system

If your dog is receiving a balanced, fresh diet, they should get everything they need to support their immune system. Still, supplements can be helpful if you are struggling to pay for the best diet you can for your pet. A quality multivitamin can help make up for lacking nutrients.

Similarly, some supplements, such as chondroitin and glucosamine, have evidence that they help manage inflammation in joints. So, your vet might recommend that your large dog be given these from puppyhood.

Similarly, older dogs might have trouble absorbing all the nutrients they need. So a good multivitamin may benefit them.

But, since multivitamins aren't adequately regulated and giving supplements in incorrect amounts can be dangerous, there are some guidelines to follow when giving your dog supplements:

  • By obtaining a Pet Assistant Membership, a nutritionist can make sure your dog needs a supplement and that they are getting it in the right amount. Supplements should be matched to the nutrients already in your dog's diet.
  • Remember, excess calcium, vitamin D, and A can be just as harmful as deficiencies, so always have a professional guide you.
  • Vitamins and supplements don't always contain what they say they do on the label. Consumerlab.com tests show that up to 60% of pet food supplements fail basic ingredient tests. Therefore, always contact the manufacturer and ask for proof of quality control and any clinical trials.

Even so, there is still some exciting research on specific nutrients and how they can boost your pet's immune system.

Vitamin E & C

Oxidative stress is a natural part of aging for humans and pets. It's simply an imbalance of free radicals and the antioxidants that make up for them.

Unfortunately, pet's who spend their lives eating dry pet food are exposed to more free radicals than they should be. Cooking at high temperatures scorches the starch and releases carcinogens. Not only that, but extruded or dry pet food has much higher rates of lipid or fat oxidation, which wears down and damages our pet's cells.

Oxidized lipids or fats stop dogs from growing and forming bones correctly and suppress their immune system. Luckily, vitamin E protects against oxidative stress and boosts the immune system overall. Dogs who are given vitamin E and selenium have a better immune response after vaccinations than dogs without.

Similarly, vitamin C may help boost the immune system by relieving oxidative stress and helps to regulate the immune system.

Vitamin D

Vitamin D is an essential nutrient in the canine diet. Still, it is one of the most common and dangerous deficiencies in homemade diets. It's also important not to give your dog any human vitamin D supplements since these can have far too much for most dogs to handle.

In the correct amount, vitamin D is most well-known for aiding bone health. In addition, research suggests it also plays a vital role in the body's defense system. So investing in a premix of fresh food can make sure your dog gets the right amount of vitamin D to boost its body's natural defenses.


Zinc is essential for several canine bodily functions. However, one of the challenges in providing your dog with zinc is that it is toxic to dogs in lower doses than many other minerals. This means that you may want to avoid adding zinc supplements to your dog's diet and rely on natural sources instead.

Zinc not only strengthens the immune system but is essential for the production of many hormones. Also, it is an active ingredient in healthy cell division and boosts cognitive function and memory.

Pet food that contains fresh, frozen, or dehydrated sources of beef, salmon, and chicken eggs are all excellent sources of zinc.

Other trace minerals and vitamins that are essential to a functioning immune system include:

  • Selenium
  • Linoleic acid
  • Vitamin B6

3. Probiotics and your dog’s immune system

Gut bacteria is an essential aspect of canine health. They are part of the first barrier defense against external invaders. Just like with mange, an imbalance in the gut's microbiome can have serious consequences. It directly impacts how well your dog can digest and absorb food and is also a key component in general health.

In fact, studies have shown that the probiotics Lactobacillus and Bifidobacterium can:

  • Improve the immune response,
  • Reduce yeast,
  • Support the immune system
  • Reduce stress
  • Reduce food allergies and diarrhea
  • Improve mood
  • Support the immune system

Because gut bacteria impacts how well your dog can absorb most of the other nutrients we have discussed, it is crucial to canine health.

4. Weight control and your dog’s immune system

Walking a dog daily to help control their weight improves a dog's immune system
A healthy weight reduces inflammation and boosts a dog’s immune system

Being overweight negatively impacts every aspect of a dog's wellbeing, including its immune system. Among the side effects are an increased risk of heart disease, diabetes, and high blood pressure.

There are also less obvious issues. Being overweight:

Any activity becomes a challenge at this point, including play.

In turn, this negatively impacts your dog's mental health. With each additional problem brought on by being overweight, your dog is at risk for further health issues, and the immune system is weakened.

Another compromising factor is that fat is actually the body's biggest endocrine gland. It produces over 40 inflammation-causing hormones. Therefore excess fat is a major contributor to chronic inflammation in the body and undermines your dog's immune response.

5. Play and exercise and your dog’s immune system

playing tug with your dog will improve their immune health
Playtime reduces stress and improves the canine immune response

Play and exercise are crucial to a dog's wellbeing since general fitness benefits canines much the same way as it does for humans. It promotes organ health, including heart health, and helps with structure and routine. Exercise also decreases fat and helps build lean muscle mass.

Daily exercise and playtime can also give your dog a sense of security and stability, and it can stave off depression.

Suppose you have ever walked into a pet shop. In that case, you may have noticed that puppies and kittens play or huddle together. They may also try to get your attention by whining or crying. At the same time, reptiles will stay motionless, alone, while they conserve energy.

This is the primary difference between reptiles and mammals and illustrates what mammals need to feel well. Overall feelings of wellness, in turn, lead to a more robust immune system.

Unlike reptiles, puppies and other mammals need physical contact, to feel safe and cared for, and to move their bodies. While playing, they also get to synchronize their movements with another dog or human, promoting bonding and a sense of togetherness.

The feeling of being safe enough to play increases feel-good chemicals and decreases stress signals from the brain. Play signals to the brain that all is well and there's no danger. It is vital for their healthy emotional and mental development that they are allowed to play often.

A dog under stress, or a dog that has suffered abuse over a long period, typically does not know how to play.

They become shut down, with their bodies drawn tight, often trying to make themselves invisible. Or they become reactive, much like a war veteran will overreact to loud noises.

These dogs usually will stay motionless when a ball is thrown and have no interest in playing tug. They need to be taught that they are safe enough to play or show curiosity and interest in their environment.

Dogs that do not play lose an overall sense of wellbeing necessary for a healthy mind, which compromises their ability to respond to disease markers.

Together with playtime, exercise releases endorphins and decreases stress.

The overall result of consistent playtime and exercise with your dog is not only a fitter pet but a happier one. Happier dogs have a stronger immune system and are far less vulnerable to disease.

6. Massage and your dog’s immune system

massage has been shown to improve a dog's immune system
Simple petting and massage can improve your dog’s immune system and quality of life

According to Dr. Rachel Barrack, BVSc, studies have shown that petting and physical contact can lower a dog's heart rate and blood pressure. It also releases oxytocin, promoting bonding.

In addition, a full-body massage has additional benefits, including helping relieve muscle tension.

In humans, massage therapy aids in relaxation, and it is the same for dogs as basic massage techniques promoting wellness. Gentle massages can also help your dog calm down, further promoting heart health.

7. Reducing stress and your dog’s immune system

Stress can kill. We know this is the case in humans, and it is no different for animals. Our dogs can suffer stress in much the same way that we do. Countless studies have shown us that stress can severely impair an animal's immune system.

Dogs that have been stuck in stressful situations for prolonged periods can become "shut down" and show many of the same hallmarks of a human with PTSD. This usually happens when a dog cannot escape its stressors, such as when locked in a noisy shelter for many months.

Typically, stress hormones and neurotransmitters are necessary, just like inflammation. If there is danger, a dog needs a jolt of adrenaline or corticosteroids to get them away from the situation. But, as soon as the threat has passed, the stress hormones should subside, and your dog should return to normal.

But if a dog goes through prolonged stress and cannot escape, little squirts of corticosteroids, cortisol, and other "warning" chemicals are constantly being secreted into their brains. This can continue even after the danger has passed.

Prolonged stress means the ability to fight off antigens is weakened. Corticosteroids and cortisol also actively suppress the immune systems by lowering the number of lymphocytes—a type of white blood cell.

Stress can be difficult to spot in dogs. The signs may be subtle and easy to miss. There are even some stress-related behaviors that mimic normal canine behavior, such as yawning.

Signs your dog is stressed include:

  • Lip licking
  • Whining or whimpering
  • Trembling
  • Pacing or restlessness
  • Hiding
  • Panting and drooling
  • Yawning

Significant life changes could cause your dog stress. These changes can be things like moving to a new home or a new puppy joining the family.

However, it could also be something seemingly trivial, like a new dog in the neighborhood or a minor change in their routine. As a dog ages, they also begin to struggle more with change.

As far as possible, stressors need to be removed. A certified behaviorist may be necessary to give your dog the essential mechanisms and skills they need to cope. A good diet, positive social interaction, and plenty of play and exercise can also offset the effects of stress.

In conclusion

Unfortunately, there are things over which we have no control, such as genetic predisposition to certain diseases and ailments. However, we can still do a great deal to offer our dogs the best possible chance at a healthy life.

There is no lifehack to doing this. After all, numerous factors impact a dog's immune system and lifespan. However, by addressing these factors proactively, you can provide your dog's body with the best possible toolkit to ward off infections and disease.

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