Yes, tuna contains iron, and it’s one of the better fish sources available. A 3-ounce serving of fresh skipjack tuna provides about 1.36 mg of iron, while canned white (albacore) tuna in oil delivers around 0.55 mg per serving. The amount varies significantly depending on the species and whether you’re eating fresh or canned.
How Much Iron Is in Different Types of Tuna
Fresh tuna steaks contain considerably more iron than canned tuna. Cooked skipjack, the species most commonly sold as “chunk light” canned tuna, has 1.36 mg of iron per 3-ounce serving when prepared fresh. That same species loses some iron through the canning process. Canned white tuna packed in oil comes in at 0.55 mg per 3-ounce serving.
The difference between water-packed and oil-packed canned tuna is minimal. Per ounce, tuna canned in water contains about 0.5 mg of iron while tuna canned in oil has 0.4 mg. For most people, this gap isn’t worth worrying about.
The FDA’s daily value for iron is 18 mg. A serving of fresh skipjack covers roughly 7.5% of that target, while a serving of canned white tuna covers about 3%. Tuna won’t single-handedly meet your iron needs, but it contributes meaningfully as part of a varied diet.
Why Tuna’s Iron Is Easier to Absorb
Not all dietary iron is created equal. Iron from animal sources, including fish, comes in a form called heme iron, which your body absorbs far more efficiently than the non-heme iron found in plants like spinach or lentils. In yellowfin tuna specifically, about 73% of the total iron is heme iron, making it highly bioavailable.
This matters if you’re trying to boost your iron levels. You could eat a bowl of fortified cereal with more total milligrams of iron on the label, but your body would absorb a smaller fraction of it compared to the iron in a piece of tuna. The FDA actually lists iron as one of the key nutrients that fish provide, alongside omega-3 fats, iodine, and choline.
Dark Meat Tuna Has More Iron
If you’ve ever noticed darker, reddish-brown sections in a tuna steak or can, that’s the dark lateral muscle. This tissue is packed with oxygen-carrying proteins that give it both its color and its iron content. Research on yellowfin tuna found that dark muscle contains 32.11 mg of iron per kilogram, higher than comparable amounts of veal or pork. The lighter flesh has less.
In canned tuna, you’ll sometimes see these darker bits mixed in. They’re perfectly safe to eat and are actually the most iron-rich part of the fish. Premium canned tuna that uses only white meat may look more appealing, but it contains less iron per bite.
Tuna vs. Other Protein Sources
Among seafood, tuna ranks near the top for iron. Here’s how a 3-ounce cooked serving compares across common proteins:
- Fresh skipjack tuna: 1.36 mg
- Pacific herring: 0.95 mg
- Canned pink salmon: 0.65 to 0.71 mg
- Wild coho salmon: 0.6 mg
- Canned white tuna: 0.55 mg
Red meat, however, is in a different league. A 3-ounce serving of beef shank delivers 3.28 mg of iron, and even a lean ground beef patty provides 2.3 mg. Lamb falls in between at roughly 1.8 to 2.4 mg per serving. If your primary goal is maximizing iron intake, red meat delivers roughly two to three times what tuna offers per serving. But tuna brings other advantages (omega-3 fats, lower saturated fat) that make it worth including alongside red meat or as an alternative.
Getting the Most Iron From Tuna
Pairing tuna with vitamin C-rich foods increases your absorption of whatever non-heme iron is present. A squeeze of lemon over a tuna steak, tomatoes in a tuna salad, or a side of broccoli all help. The heme iron in tuna is already well-absorbed on its own, but these pairings ensure you’re getting the full benefit from every source of iron on your plate.
If you’re eating tuna regularly for its iron and other nutrients, mercury is worth keeping in mind. Canned light tuna (typically skipjack) falls in the FDA’s “Best Choice” category, meaning you can safely eat two to three servings per week. Albacore, yellowfin, and fresh tuna steaks are rated as “Good Choices,” with a recommended limit of one serving per week. Bigeye tuna is the only variety the FDA says to avoid entirely due to high mercury levels. For most people, sticking to canned light skipjack offers the best balance of iron, safety, and convenience.