Can Dogs Eat Tuna? The Truth About Tuna in Your Dog’s Diet, Health Benefits, and Risks
Tuna is a staple in many human diets – it’s protein-packed, rich in omega-3 fatty acids, and convenient. So, it’s no surprise dog owners often wonder: can dogs eat tuna?
The short answer is yes — in small amounts and under the right conditions, tuna can be a healthy, high-protein addition to your dog’s diet. But it’s not a food that suits every dog, and there are several important caveats, especially regarding histamine sensitivity, mercury content, and how often and how it’s fed.
This article explores the benefits and risks of feeding tuna to dogs, when it should be avoided, how to feed it safely, and includes a free dog-friendly tuna treat recipe at the end.
Nutritional Profile of Tuna
Tuna, especially species like skipjack and albacore, is a rich source of:
High-quality protein – essential for tissue repair and maintenance
Omega-3 fatty acids (EPA and DHA) – beneficial for skin, coat, cognitive health, and joint support
Vitamins B3 (niacin), B6, and B12 – support metabolism and nervous system health
Selenium – an antioxidant that supports immune health
Phosphorus and magnesium – for bone and muscle support
According to the USDA, 100g of cooked yellowfin tuna provides:
24g protein
1g fat
108 kcal
0g carbohydrate
The Benefits of Tuna for Dogs
1. Excellent Source of Lean Protein
Tuna offers a highly digestible, low-fat protein that can support muscle maintenance in adult dogs and healthy growth in puppies (when used appropriately and not as a primary source).
2. Rich in Omega-3 Fatty Acids
Tuna contains EPA and DHA — omega-3s that:
Support brain and eye development in puppies
Improve skin and coat health
Reduce inflammation, which may help dogs with arthritis or allergies
A 2010 study published in Veterinary Therapeutics found that omega-3 supplementation significantly reduced lameness and joint pain in arthritic dogs (Roush et al., 2010).
3. Palatability
Tuna is very appealing to most dogs — its strong smell and taste can encourage picky eaters or older dogs with a reduced appetite.
4. Low in Carbohydrates
For dogs on restricted carb diets or who suffer from certain metabolic issues, tuna is naturally low in sugars and starch.
The Risks and Considerations of Feeding Tuna
While tuna has nutritional benefits, there are several serious concerns that limit its use in canine diets.
1. Mercury Accumulation
Tuna, especially larger species like albacore and bluefin, is known to accumulate mercury, a heavy metal that can be toxic over time. Unlike smaller fish such as sardines or anchovies, tuna sits high on the food chain.
High mercury levels can cause:
Kidney damage
Neurological symptoms (tremors, disorientation)
Immunosuppression
A study by Burger & Gochfeld (2004) found canned albacore tuna often exceeded recommended mercury limits for regular consumption, especially in children and pets.
SAFETY TIP:
Feed only small amounts of skipjack tuna (lower mercury levels) and limit to 1-2 times per week max. Never use it as a daily protein source.
2. Histamine Sensitivity
Dogs with allergies, particularly itchy dogs or those prone to ear infections, hot spots, or red, inflamed skin, may not tolerate tuna well.
Tuna, like many fish, is high in histamine, especially when canned or improperly stored. Histamines can exacerbate allergic symptoms.
A 2020 study published in Frontiers in Veterinary Science found that high-histamine foods may trigger pruritus (itchiness) in histamine-sensitive dogs (Olivry et al., 2020).
Avoid feeding tuna to:
Dogs with chronic skin conditions or confirmed allergies
Dogs undergoing an elimination diet or allergy testing
Dogs prone to gastrointestinal upset after eating fish
3. Sodium Levels in Canned Tuna
Many canned tuna varieties, especially those in brine, are high in sodium. Too much salt can lead to:
Dehydration
Increased blood pressure
Kidney strain in senior dogs
Choose low-sodium or no-salt-added canned tuna in spring water — avoid brine or oil-packed varieties unless rinsed thoroughly.
How to Feed Tuna to Dogs (Safely)
Best Forms:
Fresh, cooked tuna (steamed, baked, or poached – no seasoning or oil)
Canned tuna in water (low sodium, skipjack preferred)
Freeze-dried tuna treats (in moderation)
Avoid:
Tuna in brine or sunflower oil
Raw tuna (risk of parasites)
Tuna used daily or as a main meal
Tuna-flavoured kibble (often artificial and high in salt or flavour enhancers)
Serving Size Guidelines (as an occasional treat or topper):
Small dog (<10kg): 10–15g once or twice a week
Medium dog (10–25kg): 20–40g once or twice a week
Large dog (25kg+): 50–75g once or twice a week
When Tuna is Not Safe
Tuna is not suitable for every dog, especially if they suffer from:
Chronic itching or skin issues
Histamine intolerance
Kidney disease (due to phosphorus and sodium levels)
Puppies (their developing systems are more vulnerable to mercury)
Peer-Reviewed Studies & References
Roush, J. K., et al. (2010). "Multicenter Veterinary Practice Assessment of the Effects of Omega-3 Fatty Acids on Canine Osteoarthritis." Veterinary Therapeutics, 11(4), 292–306.
Olivry, T., et al. (2020). "Histamine and Pruritus: An Update on Experimental Evidence in Dogs." Frontiers in Veterinary Science, 7, 458.
Burger, J., & Gochfeld, M. (2004). "Mercury in canned tuna: white versus light and temporal variation." Environmental Research, 96(3), 239–249.
Free Recipe: Tuna & Sweet Potato Dog Treats
Great for training or an occasional high-protein snack!
Ingredients:
1 can una in spring water (drained) – approx. 145g
1 medium sweet potato, cooked and mashed (approx. 150g)
1 egg
40g buckwheat flour or oat flour (about 1/3 cup)
1 tbsp chopped parsley (optional – helps freshen breath)
Method:
Preheat oven to 160°C (320°F) / Gas Mark 3.
Mix the drained tuna and mashed sweet potato in a bowl.
Beat the egg and stir into the mix.
Add the flour and combine into a thick, sticky dough.
Spoon small blobs onto a lined baking tray or roll and cut into shapes.
Bake for 18–22 minutes, or until firm and lightly golden.
Cool completely and store in the fridge for up to 5 days or freeze for longer storage.
Makes around 25–30 small treats (depending on size).
Final Thoughts: Should You Feed Your Dog Tuna?
Tuna can be a nutritious and tempting treat for dogs, but it must be fed in moderation, with care, and only to the right dogs.
Safe for:
Healthy adult dogs
Dogs who tolerate fish well
Occasional high-reward training treats
Avoid for:
Dogs with allergies or itchy skin
Puppies
Daily feeding or full meals
Whenever introducing a new food like tuna, watch your dog’s reaction carefully. If you notice signs of digestive upset, itching, or hyperactivity, discontinue and consult your vet or canine nutritionist.
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