Feeding Senior Dogs | What Vitamins and nutrients do Senior Dogs Need?

what should we be feeding senior dogs?
what should we be feeding senior dogs?

Perhaps one of the least understood issues in dog nutrition is how senior dogs have very different nutritional requirements as they age. Aging affects everything from senior dog vitamin supplements, to macronutrients like proteins and fats. The common marketing label “for all ages” or for “all life stages” can leave owners with the misconception that they can feed one food to their dog despite age and call it a day.

This is a huge problem since as our dogs age, their nutritional requirements change quite drastically. So if you have an aging dog, what do you need to know about feeding them and their specific nutritional requirements?


Senior Dogs: How Do Nutritional Requirements Vary With Age?

What Are The Most Important Vitamins for Older or Senior dogs?

Vitamins and Supplements for Older Dogs With Failing Eyesight

Water for Senior Dogs and Food Processing

Minerals for Senior Dogs

Carbohydrates for Senior Dogs

Protein for Senior Dogs

Fat for Senior Dogs

Senior Dogs: How Do Nutritional Requirements Vary With Age?

Senior dogs and Health Complications

One of the first things to keep in mind with senior dogs is that there is no-one-size-fits-all approach to their nutrition. As dogs age, the number of comorbidities or illnesses that can affect them and their ideal nutrition can increase. For example, senior dogs with liver and renal issues, or recurring pancreatitis may need low-protein diets.

Likewise, seniors with conditions such as hypothyroidism or diabetes will also need specialized diets, often with more fiber than we would typically recommend. Senior dogs are prone to being overweight as well, which can contribute to a number of health issues including inflammation and arthritis.

If your older dog is overweight, you can read our article on the subject here.

So before choosing the best diet for your golden oldie, it is vital to first have your dog screened for health problems that can impact their ideal diet. This article will note the key nutritional differences and vitamins for healthy senior dogs. So remember that some of this will not apply to dogs with a health complication.

Adjusting the calories for your senior dog

Senior dogs can be prone to weight gain

Weight and activity levels are also a primary concern when feeding senior dogs. Some older dogs begin to lose muscle mass, so a higher calorie diet will be necessary to maintain their body weight, as muscle mass is key to their overall health.

Aside from struggling to synthesize proteins for muscle mass, older dogs also respond less to the hormone, ghrelin. Ghrelin is responsible for making a dog feel hungry. This means that tastier food with a strong smell is important to entice senior dogs who may be losing their appetite.

However, typically an older dog's energy requirements decrease by 20 – 50% as their metabolism slows down and they become less active. So the second consideration when deciding on your older dog’s diet is whether they need more calories to maintain muscle mass, or whether you need to decrease their total caloric intake because they are gaining weight.

In general, an older dog that is losing an unhealthy amount of weight, should look at a food with over 400 kilocalories per cup. A dog that is overweight or no longer needs the same amount of calories can try foods with about 300 to 350 calories per cup.

It’s important to remember that this is not just about cutting or increasing portions. Dog foods are made with a certain amount of nutrients per calorie density. So restricting the amount of a high-calorie food can mean your dog gets too few essential nutrients. Meanwhile, increasing the amount of a low calorie food can mean that senior dogs get some nutrients in excess.And yes, too much of some nutrients can be just as dangerous as too little.

So let’s look at some of the most important of the best vitamins for senior dogs.

What Are The Most Important Vitamins for Older or Senior dogs?

When it comes to senior dogs, one of the key points is that they start to lose the ability to synthesize proteins. This is where B vitamins come in, since B vitamins are crucial for this process. They also help brain function, keep cells running, and break down nutrients for the body.

Therefore, looking for a complete range of B vitamins is vital for your older dog’s health.These are:

  • B1 (thiamin)
  • B2 (riboflavin)
  • B3 (niacin)
  • B5 (pantothenic acid)
  • B6 (pyridoxine)
  • B7 (biotin)
  • B9 (folic acid])
  • B12 (cobalamin)

Of the these B vitamins, pet parents specifically want to look for:

Vitamin B1 or Thiamine

The brain and other essential organs specifically need thiamin as it breaks down the carbohydrates that fuel them. Now, there is some debate about carbohydrates in the canine diet that we will address below. For now, note that dogs can and do die of thiamine deficiencies, and as older dogs struggle to convert enough glucose into fuel for their brains, thiamine is vital.

It’s also vital to note that thiamin is one of the least stable vitamins. It degrades quickly with heat treatments, in storage, or contact with oxygen. This is why commercial dog foods often have to recall their food due to thiamine deficiencies. Thiamin can be found in liver, yeast, and meat.

AAFCO recommends 1 mg of thiamine per kilogram of food. However, this is quite a safe vitamin that you can add to your senior dog's diet since excess thiamine is just excreted in the urine.

Vitamin B6 (pyridoxine)

Vitamin B6 or pyridoxine is particularly important for senior dogs because it balances electrolytes, or sodium and potassium in the body. This is vital for heart health and water regulation. It also helps your dog absorb enough proteins and fats.

Vitamin B12 (cobalamin)

Another vitamin that is crucial for brain health, cobalamin is also vital for gut health.This vitamin is particularly important for dogs with intestinal disease or Exocrine Pancreatic Insufficiency (EPI). Like Thiamin, cobalamin is essential for vital organs and a lack of it can cause doggy dementia.

Another reason cobalamin and thiamin are so important for older dogs is because of changes in their metabolism. The way their bodies respond to insulin changes and many become more insulin resistant. These vitamins that help with carbohydrate metabolism are crucial.

Naturally, other vitamins are also key for senior dogs.

Vitamin E

Vitamin E is a powerful antioxidant that protects the brain and other tissues from free-radical damage. It is also anti-inflammatory, and essential for a healthy gut. Together with selenium, it makes a compound that massively aids the immune system, but we will discuss selenium sources below.

In general, commercial dog foods tend to supply far too little Vitamin E. What’s more, vitamin E degrades in storage, especially when it comes into contact with the copper supplements and the choline chloride that is in almost every commercial dog food. This means that like thiamin, vitamin E is one of the few supplements that you can safely add to your dog’s diet.

A good amount of vitamin E is between 300 IU/kg and 800IU/kg. This is an excellent vitamin for senior dogs that pet parents can safely supplement .

Vitamin A & D

While vitamin A and D are both essential vitamins, these should be provided in your dog’s food and never be supplemented without veterinary supervision. Too much vitamin A and D are both toxic. In fact, owners who home feed their dogs too much liver, sweet potato, or cod liver oil are the leading cause of vitamin A toxicosis in dogs.

So while your senior dog needs vitamin A & D, look for it on the label of your dog food where you should be incorporated in adequate amounts. .Ideally, you typically want to see about 12 500 IU/kg of vitamin A and about 700 IU/kg to about 1000 IU/kg. Anything more may be excessive.

Vitamin C

Vitamin C is not considered an essential vitamin for dogs, since they can synthesize it themselves. Nevertheless, it is a great antioxidant that plays a supportive role to vitamin E. For this purpose it is also a great addition to help senior dogs who are losing their eyesight

Vitamins and Supplements for Older Dogs With Failing Eyesight

Senior dogs with cloudy eyes will benefit from these antioxidants
Senior dogs with cloudy eyes will benefit from these antioxidants

When it comes to the best vitamins for senior dogs, it is also important to consider eyesight. One study had reasonable success delaying the progression of failing eyesight with a blend of the following vitamins and antioxidants you can try for your senior dog. This is a great blend of antioxidants and vitamins for older dogs whose eyes are becoming cloudy or who seem to be losing their eyesight.

  • lutein: 20 mg,
  • zeaxanthin: 5 mg,
  • β-carotene: 20 mg,
  • Astaxanthin: 5 mg,
  • vitamin C: 180 mg.

Water for Senior Dogs and Food Processing

Plenty of fresh, clean water is vital for senior dogs, who are more prone to dehydration. The general rule is about 10 – 17 ounces per 10 pounds of dog, daily. It’s also better for senior dogs to eat diets with high moisture content, such as frozen or fresh food, since this is vital for their renal health. Dry kibble can lead to low levels of dehydration that takes a toll on all the organs, but especially the kidneys and liver.

Another reason to feed your older dog fresh or frozen food, if possible, is that meat-based fresh or raw food is anti-inflammatory, while heat-processed food is inflammatory. Processed food also contains more carcinogens, as well as Advanced Glycation End-products or AGEs. AGEs are connected to far more cases of disease, ranging from heart disease to diabetes and even obesity.

Finally, heat processing also reduces levels of necessary amino acids and compounds such as taurine, L-carnitine, methionine, and lysine. You can read more about how this may contribute to heart disease in this article.

Minerals for Senior Dogs

It’s important to be careful with minerals for senior dogs, as many dog foods can supply too much. Many pet parents tend to make the mistake of thinking “the more, the better” and add supplements like calcium freely. However, excess minerals can be extremely dangerous. For example, too much phosphorus can cause renal failure and interfere with the absorption of other minerals, such as calcium, magnesium, iron, and zinc. Too much calcium is equally problematic.

Excess copper in pet food is leading to an uptick of copper storage disease in dogs and inorganic phosphates may be behind a lot of kidney damage. So keeping this in mind, we will look at a few minerals to look for in senior dogs’ diets.

Calcium and Phosphorus

Calcium and phosphorus need to be in the right ratio to work correctly, especially during the key growth period for a dog. In extremely simplistic terms, phosphorus binds with calcium in the gut and can prevent it being absorbed.

Luckily, since phosphorus levels go up with the amount of meat in the diet, there is no need to restrict phosphorus for older dogs unless they have a kidney or liver issue. Nevertheless, look for lower levels of phosphorus and calcium in your senior dog’s food. A good rule of thumb is:

  • Calcium: 0.5 to 1%
  • Phosphorus: 0.4 to 0.8%
  • Ca:P ratio: 1.1:1 to 1.4:1 (slightly more calcium than phosphorus)


Used together, selenium and vitamin E interact to create a powerful antioxidant enzyme that are fantastic for older dogs. Selenium and vitamin E both directly and indirectly affect the immune system and regulate inflammation.

However, the dietary form of selenium is important. In pet foods, the common inorganic supplement, sodium selenite, is actually capable of creating more oxidative stress, rather than acting as an antioxidant.

Some manufacturers use the nontoxic Selenomethionine (Se-Met) as a more reliable selenium source that does not release free radicals. Others prefer to use selenium yeast. Studies have shown that Se–met is an effective antioxidant that helps repair damaged DNA.


A deficiency in zinc can cause a major immunodeficiency. It may be more common than we realize, as other minerals and nutrients in the diet can inhibit zinc absorption in the gut. To that end, always look for chelated mineral zinc such as zinc proteinate or zinc amino acid chelate on the label. Zinc deficiencies are also far more common in large dogs, particularly growing puppies.

A lack of zinc can impair lymph function and cause the thymus gland to atrophy. It may even deplete bone marrow cells. Zinc is also a part of a powerful antioxidant enzyme, so a zinc-deficiency can impair the immune system on multiple levels.


Sodium is not too important unless a senior dog also has heart disease. Still, if the dog is hypertensive, then avoiding excess sodium is recommended. In these cases you don’t want to exceed the safe upper limit of 3.75 g sodium per 1000 kcal. Senior dogs with heart disease will need to be on a sodium-restricted diet.

Other essential nutrients for senior dogs:

Another good rule of thumb for senior dogs is to look for diets that specifically contain the following nutrients:

  • Taurine —essential for heart, eye, and immune system. As older dogs begin to lose white blood cells, where taurine is particularly abundant, added taurine is critical for senior dogs in their diet.
  • L-carnitine — essential for heart and brain function, as well as using fat for energy.
  • CoEnzyme Q10 — a powerful antioxidant that protects the heart.
  • Alpha-lipoic Acid — another antioxidant that can protect against cognitive decline.
  • Lactic Acid or lactates — a preservative not to be confused with lactose from milk, that the dog’s aging brain can use as an alternative source of fuel. This is helpful as they struggle to get enough glucose to the brain.
  • Casein — for senior dogs that are growing more anxious, casein seems to have some natural benzodiazepine effects to help them calm down.

Carbohydrates for Senior Dogs

There is no reason to avoid quality carbohydrates in dog food, provided it is given in moderation, or up to about 45% of dry matter in the food.

Healthy pre-cooked grains can have many of the same benefits as they do for humans. Grain allergies are extremely rare, and if an allergy does occur, it is a healthier choice to switch to a different grain rather than remove grains altogether.

The primary reason to add moderate amounts of healthy carbohydrates to a senior dog's food is because of the manner in which energy is used. Dogs and cats use between 50 & 80% of what they eat for energy alone.

This means that most of what they eat will simply be used for fuel, and not for their nutritional needs for amino acids or essential fatty acids. By providing carbohydrates, senior dog’s bodies can burn through the carbs first to meet their daily energy requirements.

This means the protein and fat in the food can then be better used by the body where needed.

Carbohydrates are also easier to digest, so breaking down carbohydrates puts less pressure on organs like the pancreas, liver, and kidneys. Dogs that have issues with these organs will typically need to go on a high-carb, low-protein diet to relieve the pressure of digesting protein.

Protein for Senior Dogs

Older dogs need more protein unless they have a renal or liver problem or some other condition that contraindicates high-protein. Senior dogs do not have a problem digesting protein, but they do have a problem with protein synthesis. Therefore, the crude protein in the diet should be about 30%, possibly going up to 45% as needed.

Increasing the amount of protein can also help if the dog is overweight and needs to have their calories restricted.

The source of the protein is also important. Keep in mind, dogs with certain healthy conditions such as liver shunts may need more protein from plant or dairy sources, but if your senior dog is healthy, then always choose high-quality animal proteins.

The best protein sources are extremely digestible, such as eggs, poultry, and fish. Pork is a no no, and red meat like beef should not be the staple of senior dogs diets. In studies on Golden Retrievers, red meat is linked to more cases of cancer.

You can also go ahead and avoid lamb for your older dog. Lamb and lamb meal is low in taurine and the cysteine in it is not bioavailable to dogs and cats. Cysteine is an amino acid that dogs need to create taurine in their bodies. Thus, lamb and lamb meal-based foods have been linked to taurine deficiencies that cause heart disease.

Fat for Senior Dogs

Fat should be either increased or decreased according to the dog's weight. For an underweight senior dog, fat can be moved up to 20%, keeping an eye on possible issues like pancreatitis or bloat. To avoid bloat for a larger senior dog, feed a varied diet at least twice a day and make sure that fat is not within the first five ingredients of dog food.

For an overweight dog, fat can be decreased to around 10 – 12% to reduce calories.

The type of fat is also important. EPA is an omega-3 fatty acid that is most abundant in fish oils or krill oil. It is a powerful anti-inflammatory and essential for a healthy gut. Likewise, DHA is another Omega-3 fatty acid found most readily in fish oils. DHA is particularly vital for older dogs as it is essential for brain function. So senior dogs have an increased need for more DHA in their diets than normal adult dogs.

Omega-3s that come from plant sources are called ALA. This is a good antioxidant, but a dog needs to convert it to EPA and DHA. Their bodies are not very good at doing this, so marine oils are better. But there is one caveat: marine oils go rancid extremely quickly. So making sure your senior dog gets fresh, non-oxidised marine oil is the challenge.

The other essential fatty acid for dogs is the omega-, linoleic acid (LA). This is great for skin and coat health as well as the immune system. Studies suggest that the ideal ration of omega-6 to omega-3 is about 5:1 for optimal immune function.

However, if your senior dog has chronic inflammation such as osteoarthritis, you want to increase the amount of anti-inflammatory omega-3s in the diet to a ratio of about 1:1.

One last fat that can help the brain and heart health of senior dogs is purified MCT oil. For a full run down on why MCT may be so beneficial for older dogs, you can read this article. Keep in mind, MCT oil should not be confused with coconut oil that is high in saturated fats. In fact, dog food that uses beef fat or pork fat is also best avoided because saturated fats are not great for dogs in general.

Final Thoughts

As we can see, it’s clear that senior dogs have very specific dietary needs. There is no one-size-fits all guide to nutrition, but here we outlined some of the best vitamins for seniors, as well as their macronutrient and mineral needs.