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We all want as many years with our Mastiffs as possible. As your Mastiff ages, you may be looking for additional ways to support their health.
The following list of supplements is among the top recommended products for senior Mastiffs. As always, be sure to consult your own veterinarian before making any changes to your Mastiff’s dietary or medical regimen.
1. Glucosamine & Chondroitin for Supporting Your Senior Mastiff’s Aging Joints
Joint pain and arthritis are some of the most common ailments an aging Mastiff will face. Supplements containing glucosamine aid in replacing lost joint fluid, providing much-needed lubrication and cushioning to stiff, achy joints. Chondroitin sulfate has been shown to improve the structural integrity of joints by repairing damaged cartilage and preventing further cartilage breakdown.
You can learn more about the glucosamine and chondroitin supplement iHeartDogs recommends here.
2. Probiotics for Immune & Gut Support for Your Senior Mastiff
Probiotics are supplements containing large doses of microorganisms. They promote a healthy GI tract by allowing the “good” bacteria in the gut to flourish. “Bad” bacteria often accumulate due to stress, illness, and long-term medication use. Since the majority of your senior dog’s immune system is located in the gut, probiotics also help to maintain health throughout the body.
We’d recommend looking into a 3-in-1 probiotic that also contains prebiotics and digestive enzymes.
3. Omega-3 Essential Fatty Acids to Fight Inflammation & Reduce Itchy Skin for Your Senior Mastiff
Older dogs may experience dry, itchy skin and dull, brittle coats. Adding Omega-3 and Omega-6 fatty acids to a senior dog’s diet can reduce inflammation and promote healthy skin and a soft, shiny coat. Omega-3 fatty acids also support healthy mobility and bone health. Additional benefits in the body include allergy support, heart health, strong brain function, and visual acuity.
Krill oil is one of the best sources of Omega-3 available, as it contains a special form of fatty acids that are more usable in your dog’s body. Additionally, many high-quality krill supplements contain a powerful compound called astaxanthin, a highly potent antioxidant.
4. Milk Thistle for Your Mastiff’s Liver & Kidney Support, Especially for Dogs Taking Pain Meds
Natural milk thistle is said to protect the liver from damage and may actually improve liver function. This is important for aging Mastiffs, especially those with existing liver problems and those taking medications known to be taxing on the liver. For example, any dog regularly taking an NSAID pain medication such as carprofen, Novox, Rimadyl, deracoxi, Deramaxx, firocoxib, Previcox, meloxicam, Metacam, grapipant, or Galliprant may need additional liver support. Make sure to discuss this with your vet.

5. Curcumin (from Turmeric) for Pain & Inflammation
This “wonder spice” is a derivative of turmeric and promotes brain and joint health in aging Mastiffs. Some studies have suggested that turmeric can provide nearly the same pain relief as an NSAID drug. Lastly, curcumin is also known for its possible anti-tumor properties and in helping to support dental health.
Many high-quality hip and joint supplements, such as this one, contain turmeric in the formula.
6. Hemp Oil for Your Senior Mastiff’s Pain & Inflammation
No discussion of senior dog supplements would be complete without discussing hemp. In the last 5 years, several studies have begun to show great promise for hemp in helping to alleviate joint pain, calm nervous dogs, reduce inflammation caused by allergies, and reduce seizures in epileptic pups.
We’d recommend a hemp oil or hemp chew that contains 0% THC, as well as using a product that is tested multiple times throughout the manufacturing process to ensure a pure and potent product. Here at iHeartDogs, we only sell and recommend the Cannanine brand.
7. Fiber for Your Senior Mastiff’s Digestive Health
Senior dogs may experience changes in the lining of the intestines, which lowers their ability to digest and absorb the nutrients in their food. Adding healthy fiber to your older pup’s diet supports a healthy digestive system, combats constipation, and promotes overall health.

8. Extra-Protein for General Mastiff Aging Support
As your Mastiff’s body ages, it breaks down muscle and tissues at a faster rate than before. For this reason, aging dogs need extra protein in their diet (note: there are some exceptions, such as if your senior dog has chronic kidney disease, in which your vet may recommend a lower protein diet).
Many senior Mastiff parents opt to add additional protein to their dog’s kibble, such as a cooked or raw egg, chicken breast, or a freeze-dried dog food topper. Surprisingly, most kibbles only contain around 20-30% protein, so boosting this vital nutrient can be very helpful for seniors. It can also substantially help their appetite!
9. Dog-Safe Mushrooms such as Shiitake, Turkey Tail, & Reishi for Immune Boosting Support
Mushrooms are an incredibly exciting area of emerging nutritional studies. Some clinical trials have shown great promise in extending the lifespan of dogs battling cancer. And while it’s not a miracle, mushrooms like Reishi, Turkey Tail, and Shiitake can undoubtedly boost the immune system of your Mastiff.
As you are probably aware, many mushrooms can be toxic to dogs, especially those found in your yard. Make sure to use a dog-safe mushroom supplement if you choose to give one to Fido. This particular formula contains 6 different mushrooms, as well as organic chicken bone broth.
10. Collagen-rich bone Broth, which supports healthy joints and skin in seniors
One of the biggest causes of early death in Mastiffs is reduced mobility. Bone broth is packed with joint-supporting nutrients like glucosamine, chondroitin, and collagen, all of which help keep your older pup mobile longer. In addition, most senior dogs LOVE the flavor, and it will boost the nutrition and taste of their current food.
The product iHeartDogs recommends and sells contains both bone broth and 6 different immune-supporting mushrooms.
FAQs About the Best Supplements for a Senior Mastiff
1. What supplements are most beneficial for senior Mastiffs?
Senior Mastiffs benefit most from joint support supplements (glucosamine, chondroitin, MSM), omega-3 fatty acids for skin and heart health, probiotics for digestion, and multivitamins to cover nutritional gaps.
2. Why do older Mastiffs need supplements?
As Mastiffs age, they face issues like arthritis, reduced mobility, weaker immune systems, and digestive changes. Supplements help maintain joint health, improve energy, and support their overall quality of life.
3. Are joint supplements necessary for senior Mastiffs?
Yes. Large breeds like Mastiffs are prone to hip dysplasia and arthritis. Joint supplements with glucosamine, chondroitin, MSM, and green-lipped mussel can ease stiffness and improve mobility.
4. Can supplements help my Mastiff’s digestion?
Absolutely. Probiotics and digestive enzymes support gut health, reduce bloating (a risk for Mastiffs), and improve nutrient absorption, which is crucial for older dogs.
5. What role do omega-3 fatty acids play for senior Mastiffs?
Omega-3s (from fish oil or krill oil) help reduce inflammation, support joint health, maintain brain function, and keep your Mastiff’s skin and coat healthy.
6. How do I know if my Mastiff needs supplements?
Look for signs like joint stiffness, decreased energy, dull coat, digestive issues, or trouble standing up. A veterinarian can confirm which supplements would be most helpful.
7. Can I give human supplements to my Mastiff?
It’s not recommended. Human supplements may contain unsafe doses or harmful ingredients for dogs. Always use veterinary-formulated supplements for safety.
8. Are there multivitamins for senior Mastiffs?
Yes. Senior dog multivitamins provide a balance of essential vitamins and minerals to fill dietary gaps and support immune and organ health in older Mastiffs.
9. Do senior Mastiffs need hip and joint chews?
Yes, joint chews are a convenient way to deliver glucosamine, chondroitin, and MSM, which help keep hips and joints strong and reduce pain in senior Mastiffs.
10. Can supplements improve my Mastiff’s energy levels?
Yes. Supplements that support heart health, digestion, and joint mobility can make your Mastiff feel more energetic, active, and comfortable in daily activities.
11. Are there supplements to help my Mastiff’s heart health?
Coenzyme Q10 (CoQ10), taurine, and omega-3 fatty acids are commonly used to support cardiovascular health in senior Mastiffs.
12. How do probiotics benefit a senior Mastiff?
Probiotics help balance gut bacteria, improve digestion, strengthen immunity, and reduce issues like diarrhea, constipation, or gas in aging Mastiffs.
13. How should I give supplements to my Mastiff?
Supplements are available as chews, powders, capsules, and liquids. Chews are the easiest for large breeds, but you should choose a form that works best for your Mastiff’s preferences.
14. Can supplements prevent arthritis in Mastiffs?
Supplements cannot prevent arthritis completely, but starting joint support early may slow its progression and keep your Mastiff more mobile as they age.
15. Should I consult my vet before giving supplements?
Yes. A veterinarian can recommend the right dosage, ensure supplements don’t interfere with medications, and guide you to the safest, most effective products.
The Food and Drug Administration has not evaluated these statements. This product is not intended to diagnose, treat, cure, or prevent any disease. The information on this website is not intended to replace the advice of a qualified healthcare professional in a one-on-one relationship.
Related: Top Pet Insurance Plans for Mastiffs

Choosing the Best Supplements for a Senior Mastiff
As Mastiffs age, their nutritional needs change, making the right supplements an essential part of their daily care. From joint support to digestive health and immune-boosting formulas, high-quality supplements can help keep your senior Mastiff active, comfortable, and happy. Always consult your veterinarian before adding new supplements to ensure they match your dog’s specific health needs. By choosing the best senior dog supplements, you’ll support your Mastiff’s overall well-being and give them the healthy, happy golden years they deserve.









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