Is 2 cans of tuna a day okay?: Mercury, Nutrition, and Safer Choices

October 8, 2025 •

4 min read

According to the Food and Drug Administration (FDA), consuming two or more cans of albacore tuna per week can put an individual at risk of exceeding safe mercury levels. While canned tuna offers a convenient and affordable source of protein and omega-3s, regularly eating 2 cans of tuna a day is generally not advised due to the potential for mercury accumulation in the body. The exact safety depends on the type of tuna, individual body weight, and other dietary factors, but moderation is key for a healthy nutrition diet.

Quick Summary

The high mercury content in some tuna varieties, especially albacore, makes eating multiple cans daily a health risk. Recommended intake limits vary by tuna type and individual factors, with light tuna generally being a safer option. To minimize mercury exposure while retaining nutritional benefits, diversifying seafood intake and choosing low-mercury fish is advisable. Vulnerable groups, like pregnant women and children, face stricter consumption limits.

Key Points

Mercury Is the Primary Concern: Tuna, especially larger varieties like albacore, contains mercury, a heavy metal that can cause neurological damage if it accumulates in the body over time.
Type of Tuna Matters: Canned light tuna (typically skipjack) has significantly lower mercury levels than canned albacore (white) tuna.
Two Cans Daily Exceeds Recommendations: Consuming two cans of any tuna variety daily is well beyond the FDA's recommended weekly limits, especially for albacore.
Diversify Your Protein Sources: To mitigate mercury risk, substitute tuna with other low-mercury fish like salmon, sardines, or cod, or with other protein sources such as chicken and eggs.
Special Populations Need Caution: Pregnant women, breastfeeding mothers, and young children are more sensitive to mercury's effects and have much stricter consumption limits.
Moderation is Key: Occasional tuna consumption is safe and healthy, but regularly eating large amounts can be detrimental to your health.

Tuna's Nutritional Rewards and Mercury Risk

Canned tuna is a staple for many, prized for its affordability, long shelf-life, and rich nutritional profile. It's an excellent source of lean protein, which is vital for building and repairing tissues, and it contains essential nutrients like vitamin D, B12, selenium, and iron. Perhaps most notably, tuna provides heart-healthy omega-3 fatty acids, specifically DHA and EPA, which are linked to improved brain and heart health. However, the primary concern surrounding frequent tuna consumption is its mercury content. As a larger, predatory fish, tuna can accumulate higher levels of methylmercury from its environment. This neurotoxin can build up in the human body over time and, in high amounts, can cause severe health issues affecting the nervous system, brain, and kidneys.

Decoding Tuna Varieties: Light vs. Albacore

Not all canned tuna is created equal when it comes to mercury levels. The species of tuna used significantly impacts its mercury concentration. This is because larger, longer-living species have more time to accumulate the heavy metal than smaller, younger ones. This distinction is crucial for determining safe consumption levels.

Most canned light tuna is made from skipjack, a smaller, fast-growing tuna species. It has lower mercury levels than other tuna types, making it the safest option for more frequent consumption. The FDA and EPA classify canned light tuna as a "Best Choice" for this reason. Conversely, canned white tuna is almost exclusively made from albacore tuna, a larger species that contains significantly higher mercury concentrations—often three times more than light tuna. Other species, like yellowfin, are also higher in mercury and should be consumed sparingly.

The Impact of 2 Cans a Day

If considering two 5-ounce cans of tuna daily, the type of tuna is the primary factor dictating the risk. With canned light (skipjack) tuna, you'd be consuming around 10 ounces per day, or 70 ounces per week. With albacore (white) tuna, this would be 10 ounces daily, or 70 ounces weekly. The risks associated with each are dramatically different.

For Canned Light (Skipjack) Tuna: The FDA recommends 2-3 servings per week, with a serving being about 4 ounces. At 10 ounces daily, you would exceed the weekly recommended intake by over 600%. While some sources suggest slightly higher limits, consuming this much tuna would still be considered excessive and could lead to mercury accumulation over time, especially when considering individual differences in weight and sensitivity.
For Canned Albacore (White) Tuna: The FDA recommends only one 4-ounce serving per week for adults. A daily consumption of two cans, or 10 ounces, would far exceed this recommendation and is considered unsafe due to the high mercury content. Consistently consuming high-mercury fish can result in chronic mercury poisoning, which may manifest as neurological symptoms like memory loss, tingling, and tremors.

Table: Tuna Type Comparison


Feature	Canned Light Tuna (Skipjack)	Canned Albacore Tuna (White)	Other Large Tuna (e.g., Fresh Yellowfin)
Mercury Content	Low	High (approx. 3x light tuna)	High (similar to albacore)
FDA/EPA Category	Best Choice	Good Choice	Good Choice/Higher Mercury
Weekly Adult Limit	2-3 servings (8-12 oz)	1 serving (4 oz)	1 serving (4 oz)
Typical Can Size	~5 ounces	~5 ounces	N/A (sold as steak)
Risk of Over-consumption	Lower (but still present with high intake)	Significant	Significant
Flavor Profile	Milder, softer texture	Firmer texture, mild flavor	Richer, more intense flavor
Common Uses	Sandwiches, salads, casseroles	Salads, sandwiches, standalone	Sushi, sashimi, grilled steaks

Healthier Alternatives and Dietary Considerations

To reap the health benefits of seafood while mitigating mercury risks, variety is key. The Dietary Guidelines for Americans recommend consuming 8 to 12 ounces of seafood per week, from a variety of low-mercury options. Incorporating other fish and protein sources can provide a wider range of nutrients and prevent excessive mercury exposure.

Low-mercury seafood alternatives:

Salmon
Sardines
Mackerel
Sardines
Shrimp
Cod
Tilapia

Plant-based and other protein sources:

Eggs
Chicken breast
Beans and lentils
Tofu
Greek yogurt

Conclusion

While two cans of canned light tuna daily is likely not an immediate threat for a healthy adult, it significantly exceeds official health recommendations and increases the risk of mercury accumulation over time. Eating two cans of higher-mercury albacore tuna daily is actively discouraged and poses a notable health risk. The most prudent approach to including tuna in your nutrition diet is moderation. By limiting intake, opting for lower-mercury light tuna, and diversifying protein sources with other healthy seafood and alternatives, you can enjoy the nutritional advantages of tuna without the potential dangers of heavy metal toxicity. For those with specific health conditions, or if you are pregnant or breastfeeding, seeking advice from a healthcare professional is crucial. Consulting the FDA's detailed guidelines on seafood consumption can also provide more specific information tailored to different populations.

Outbound Link

For the latest information and advisories, consult the official U.S. Food and Drug Administration's guidance on mercury levels in commercial fish and shellfish: FDA: Mercury Levels in Commercial Fish and Shellfish

Frequently Asked Questions

The main health risk is mercury poisoning. High levels of methylmercury, a neurotoxin found in tuna, can lead to neurological issues such as memory loss, muscle weakness, and impaired speech or hearing over time.

Yes, canned light tuna, typically made from skipjack, contains significantly lower mercury levels than canned albacore (white) tuna. For this reason, the FDA classifies it as a safer "Best Choice" for more frequent consumption.

For most adults, the FDA recommends limiting canned albacore tuna to one 4-ounce serving per week. For canned light tuna, 2 to 3 servings (8-12 ounces) per week is considered safe, especially when not eating other fish.

While mercury poisoning from tuna is rare for those who consume it in moderation, regularly exceeding recommended intake, especially of high-mercury varieties like albacore, can lead to a buildup of mercury in the body and pose health risks.

Yes, vulnerable populations should be more cautious. This includes pregnant or breastfeeding women and young children, who should stick to FDA guidelines for low-mercury fish and limit their intake more strictly.

For protein and omega-3s without high mercury risk, consider low-mercury seafood options like salmon, sardines, and shrimp. Other alternatives include chicken, eggs, beans, and lentils.

No, cooking canned tuna does not reduce its mercury content. Methylmercury is tightly bound to the fish protein and is not removed by heat. The canning process itself is a form of cooking and does not affect the mercury levels.