Tuna is one of the leanest protein sources you can eat. A serving of light tuna canned in water gets roughly 93% of its calories from protein and only about 7% from fat. Even fattier tuna species like bluefin remain low-fat compared to most other animal proteins. What fat tuna does contain is largely the omega-3 type that benefits your heart and brain.
Fat Content by Type of Tuna
Not all tuna is equally lean. The species matters, and so does how it’s packed or prepared. Here’s how the most common forms compare.
Canned light tuna in water is the leanest option most people encounter. A one-ounce serving contains just 0.9 grams of total fat and 0.2 grams of saturated fat. Scale that up to a typical 3-ounce serving and you’re looking at under 3 grams of fat total.
Canned tuna in oil bumps the fat content up noticeably. The same one-ounce portion packed in oil has 2.3 grams of total fat and 0.4 grams of saturated fat. That’s more than double the water-packed version. Draining the oil helps, but the tuna still absorbs a good amount during packing. If you’re watching fat intake closely, water-packed is the better pick.
Fresh bluefin tuna is the fattiest species, carrying more natural oil in its flesh. That’s exactly what makes it prized for sushi. Even so, a 3-ounce cooked portion of bluefin typically contains around 5 to 6 grams of fat, which is still modest by any standard.
Albacore (white tuna) falls in the middle. It has more fat than skipjack (the species in most “light” cans) but less than bluefin. Yellowfin is similarly lean to skipjack.
Flavored tuna pouches stay surprisingly low in fat. A StarKist Sweet & Spicy pouch, for example, contains just 0.5 grams of total fat per serving. The added ingredients in these products tend to contribute sugar or sodium, not fat.
The Fat in Tuna Is Mostly Omega-3
What makes tuna’s small amount of fat worth paying attention to is its quality. Tuna is one of the richest sources of EPA and DHA, the two omega-3 fatty acids linked to lower heart disease risk, reduced inflammation, and better brain function.
Per 100 grams of fish, bluefin tuna delivers about 1.2 grams of DHA and 0.4 grams of EPA. Albacore provides roughly 1.0 gram of DHA and 0.3 grams of EPA. Even generic canned tuna still provides 0.4 grams of DHA and 0.1 grams of EPA per 100 grams. These numbers make tuna competitive with salmon for omega-3 content, particularly the fattier species.
Saturated fat, the type you generally want to limit, is minimal across all tuna varieties. Water-packed canned tuna has just 0.2 grams of saturated fat per ounce. You’d need to eat an enormous amount of tuna before saturated fat became a concern.
How Tuna Compares to Other Proteins
To put tuna’s fat content in perspective, consider what else you might eat for protein. A 3-ounce serving of 85% lean ground beef contains around 13 grams of fat. The same portion of chicken thigh with skin has about 9 grams. A 3-ounce serving of salmon runs 6 to 10 grams depending on the species. Water-packed tuna at under 3 grams per 3-ounce serving is leaner than virtually all of these.
That protein-to-fat ratio is why tuna is a staple for people focused on building muscle or losing weight. You get a large amount of protein per calorie without significant fat coming along for the ride.
What Raises the Fat in a Tuna Meal
Plain tuna is very low in fat, but what you add to it often isn’t. A tablespoon of mayonnaise in tuna salad contributes about 10 grams of fat on its own, more than tripling or quadrupling the fat in the tuna itself. Oil-based dressings, cheese melted on a tuna melt, and buttered bread all shift the nutritional profile dramatically.
If keeping fat low matters to you, mixing tuna with Greek yogurt, mustard, lemon juice, or avocado (which adds fat, but the unsaturated kind) gives you flavor without turning a lean protein into a high-fat dish. Choosing water-packed over oil-packed cans is the other easy lever to pull.
How Much Tuna You Can Safely Eat
Fat isn’t the limiting factor for tuna consumption. Mercury is. The FDA recommends eating at least 8 ounces of seafood per week, and tuna can be part of that, but the species you choose matters.
Canned light tuna, which is mostly skipjack, falls in the FDA’s “Best Choices” category, meaning you can safely eat two to three servings per week. Albacore (white tuna), yellowfin, and fresh or frozen tuna are classified as “Good Choices,” with a recommendation of one serving per week. Bigeye tuna is the one to avoid entirely due to high mercury levels.
For pregnant or breastfeeding women, the FDA recommends 8 to 12 ounces of lower-mercury seafood per week, with a single serving defined as 4 ounces. Children need smaller portions: about 1 ounce at ages 1 to 3, scaling up to 4 ounces by age 11, with two servings per week from the “Best Choices” list.