Canned tuna is one of the most affordable protein sources in the grocery store — a single can costs about $1 to $3 and delivers a full meal’s worth of protein. But mercury concerns have made many people nervous about eating it regularly. Is canned tuna healthy, and how often can you safely eat it? A 3-ounce serving of canned light tuna provides about 100 calories, 22 grams of protein, and less than 1 gram of fat, along with meaningful selenium, vitamin D, and omega-3 fatty acids. The mercury question has a straightforward answer that depends on the type of tuna you choose and how much you eat per week. Here is what the science says about balancing tuna’s real benefits against its real risks. For more evidence-based nutrition information, see our wellness guide.
Canned Tuna Nutrition Breakdown
According to the USDA FoodData Central database, a 3-ounce (85 gram) serving of canned light tuna packed in water (drained) provides approximately 100 calories, 22 grams of protein, 0.7 grams of fat, 0 grams of carbohydrates, 60 mcg of selenium (109% DV), 1.7 mcg of vitamin D (9% DV), 8.6 mg of niacin (54% DV), and about 200 mg of omega-3 fatty acids (EPA and DHA combined).
Canned albacore (white) tuna has a slightly different profile: approximately 109 calories, 20 grams of protein, 2.5 grams of fat, and roughly 500 mg of omega-3s per 3-ounce serving. The higher fat content in albacore translates to more omega-3s — a significant advantage for heart health — but also more mercury, which is the primary trade-off between the two types.
The protein-to-calorie ratio in canned tuna is exceptional. At 22 grams of protein per 100 calories, it matches or exceeds chicken breast, egg whites, and most other lean protein sources. For people focused on high-protein diets, building muscle, or managing weight, canned tuna is remarkably efficient. One can (about 5 ounces drained) delivers roughly 37 grams of protein — more than half the daily recommended intake for a 150-pound adult.
Mercury in Canned Tuna: The Real Risk
Mercury is the primary safety concern with tuna consumption. All fish contain some methylmercury — a neurotoxin that accumulates in larger, longer-lived predatory fish. Tuna, as a large predatory species, contains more mercury than smaller fish like sardines, anchovies, or salmon.
The FDA categorizes fish into “Best Choices” (2-3 servings per week), “Good Choices” (1 serving per week), and “Choices to Avoid.” Canned light tuna (typically skipjack) is in the “Best Choices” category, with an average mercury concentration of about 0.12 parts per million (ppm). Canned albacore (white) tuna falls into “Good Choices,” with an average mercury concentration of about 0.32 ppm — nearly three times higher than light tuna.
Based on FDA and EPA joint guidelines, most adults can safely eat 2 to 3 servings (8 to 12 ounces) of canned light tuna per week or 1 serving (4 ounces) of albacore tuna per week. Pregnant women, nursing mothers, and young children should stick to the lower end of these ranges. The EPA sets a reference dose for methylmercury at 0.1 mcg per kilogram of body weight per day — for a 150-pound adult, that allows for about 6.8 mcg of mercury daily, which translates to roughly two 6-ounce cans of light tuna per week.
Light Tuna vs Albacore: Which Is Better?
The choice between light and albacore tuna involves a clear trade-off: albacore delivers more omega-3 fatty acids but also more mercury. Here is a direct comparison per 3-ounce serving.
Canned light tuna (skipjack): 100 calories, 22g protein, 200mg omega-3s, 0.12 ppm mercury average. Canned albacore (white) tuna: 109 calories, 20g protein, 500mg omega-3s, 0.32 ppm mercury average. Light tuna has a milder, softer flavor and falls apart more easily — it works well in casseroles, pasta, and mixed dishes. Albacore has a firmer texture and more pronounced flavor, making it better for tuna salads and sandwiches where the fish is the star.
For most people, alternating between the two is a reasonable strategy. If you eat tuna twice a week, one serving of each type keeps your mercury exposure moderate while providing more omega-3s than light tuna alone. If you eat tuna more than twice a week, stick primarily to light tuna to stay within safe mercury limits. Pregnant women should default to light tuna and limit total tuna consumption to 2 to 3 servings per week.
Omega-3 Benefits of Canned Tuna
Omega-3 fatty acids — specifically EPA and DHA — are among the most studied nutrients in nutrition science. The American Heart Association recommends eating fish at least twice a week, primarily for the cardiovascular benefits of omega-3s. These fatty acids reduce triglycerides, lower blood pressure slightly, decrease the risk of arrhythmias, and slow the progression of atherosclerotic plaque.
Canned albacore tuna delivers about 500 mg of combined EPA and DHA per serving — roughly one-third of the 1,000 to 2,000 mg daily intake that many cardiologists recommend for people with existing heart disease. Light tuna provides less (about 200 mg) but still contributes meaningfully when eaten regularly. For comparison, a 3-ounce serving of salmon provides about 1,500 mg — but salmon costs two to four times more per serving than canned tuna.
Beyond heart health, omega-3s play roles in brain function, joint inflammation reduction, and fetal brain development during pregnancy. For people who do not eat fish regularly, canned tuna is one of the most accessible and affordable ways to increase omega-3 intake without supplements.
Practical Tips for Eating Canned Tuna
Choosing between water-packed and oil-packed tuna affects the nutrition profile. Water-packed tuna is lower in calories (100 vs 150 per serving) and fat, but draining oil-packed tuna also removes some of the omega-3s that dissolve into the oil. If you drain oil-packed tuna, you lose roughly 25% of the omega-3 content. Water-packed tuna retains its omega-3s when drained. For most health goals, water-packed is the better default.
Sodium content varies by brand. A single can of tuna may contain 200 to 400 mg of sodium. Low-sodium varieties are available and typically contain 50 to 100 mg. If sodium is a concern, choose low-sodium options or rinse the tuna briefly under water before eating — this reduces sodium by about 30% without significantly affecting taste.
Canned tuna pairs well with high-fiber and nutrient-rich foods. Mix it with mashed avocado instead of mayo for a heart-healthy tuna salad. Add it to rice bowls with vegetables. Layer it on whole-grain bread with greens. Combine it with cooked pasta, olive oil, capers, and cherry tomatoes for a quick Mediterranean-style dish. If you enjoy hummus, tuna and hummus on whole-grain crackers makes a high-protein snack with minimal prep.
Who Should Limit Canned Tuna
While canned tuna is safe for most people in recommended amounts, certain groups should be more cautious. Pregnant and breastfeeding women should eat no more than 8 to 12 ounces of low-mercury fish per week (including light tuna) and no more than 4 ounces of albacore per week, per FDA guidance. Children under 10 should eat smaller portions — the FDA provides age-based serving size recommendations ranging from 1 ounce for children aged 1 to 3 to 3 ounces for children aged 4 to 7.
People who eat fish very frequently — five or more servings per week — should vary their fish choices rather than relying heavily on tuna. Rotating between tuna, salmon, sardines, shrimp, and tilapia distributes mercury exposure and broadens nutrient intake. Individuals with kidney disease should discuss fish consumption with their healthcare provider, as the high protein content may need to be managed alongside other dietary protein sources.
Frequently Asked Questions
How many cans of tuna can you eat per week?
For most adults, 2 to 3 cans of light (skipjack) tuna per week or 1 can of albacore (white) tuna per week is considered safe based on FDA and EPA guidelines. Pregnant women should stay at the lower end. These recommendations are designed to keep methylmercury exposure below levels associated with health effects.
Is canned tuna as nutritious as fresh tuna?
Canned tuna retains most of the protein, selenium, and B vitamins found in fresh tuna. Omega-3 content may be slightly lower in canned tuna due to processing, and sodium is typically higher. Fresh tuna steaks (especially ahi/yellowfin) tend to have higher mercury levels than canned light tuna. For everyday meals, canned tuna is a nutritionally sound and far more affordable alternative.
Is tuna good for building muscle?
Absolutely. At 37 grams of protein per can with virtually no fat (in water-packed varieties), canned tuna is one of the most protein-dense foods available. Bodybuilders and athletes have relied on canned tuna as a staple protein source for decades. Pair it with rice or whole grains for a complete post-workout meal that provides both protein and carbohydrates for recovery.
Does canned tuna have BPA?
Some canned tuna is packaged in cans lined with BPA-containing epoxy. However, many brands have transitioned to BPA-free or BPA-NI (non-intent) linings. If BPA is a concern, look for brands that explicitly state “BPA-free lining” on the label, or choose tuna packaged in pouches rather than cans — pouches typically do not contain BPA.
The Bottom Line
Canned tuna is one of the healthiest, most affordable, and most convenient protein sources available. It delivers exceptional protein per calorie, meaningful omega-3 fatty acids, and important micronutrients like selenium and niacin. The mercury concern is real but manageable — choosing canned light tuna and staying within 2 to 3 servings per week keeps most adults well within safe limits. For the price of a few dollars per week, canned tuna provides nutritional value that rivals far more expensive protein sources. Buy water-packed, rotate between light and albacore, vary your fish choices across the week, and enjoy it as a regular part of a balanced diet.