Can you get mercury from eating canned tuna? What You Need to Know

October 23, 2025 •

4 min read

According to a November 2022 survey, about a third of Americans eat canned tuna two or more times a month, highlighting its popularity as a pantry staple. The question, "Can you get mercury from eating canned tuna?", is a common one, and the answer is that while mercury is present, the level depends significantly on the type of tuna you choose. This article will demystify the mercury issue, providing the facts needed to make informed and healthy choices.

Quick Summary

Canned tuna contains varying levels of mercury depending on the species. Smaller, younger fish like skipjack have less mercury than larger albacore. Understanding these differences and consuming in moderation are key to mitigating health risks.

Key Points

Source of Mercury: Mercury exists naturally in the environment but accumulates in fish, with levels varying by species, size, and age.
Light vs. Albacore Tuna: Canned light tuna (typically skipjack) is a better choice as it comes from smaller fish and contains significantly less mercury than canned white (albacore) tuna.
Serving Recommendations: The FDA recommends varying serving sizes based on tuna type, with higher allowances for light tuna (2-3 servings/week) and lower for albacore (1 serving/week).
Vulnerable Populations: Pregnant women, breastfeeding mothers, and young children are particularly susceptible to mercury's neurotoxic effects and should strictly follow specific consumption guidelines.
Mitigating Risk: Practicing moderation, diversifying your seafood intake with other low-mercury fish like salmon and sardines, and checking brand information are key to minimizing mercury exposure.
Health Benefits: Despite the mercury risk, canned tuna remains a valuable source of high-quality protein and omega-3 fatty acids when consumed within recommended guidelines.

The Origins of Mercury in Fish

Mercury is a naturally occurring element present in the earth's crust, but human industrial activities like coal burning and mining have significantly increased its concentration in the atmosphere and oceans. Once in the water, bacteria convert it into a highly toxic form called methylmercury, which is easily absorbed by marine life.

Fish and other seafood absorb methylmercury from the water and through their diet. Due to a process called bioaccumulation, mercury levels increase as it moves up the food chain. Larger, predatory fish eat smaller, mercury-contaminated fish, and since mercury is not easily excreted, it builds up in the larger fish's muscle tissue over its lifetime. This places long-lived, predatory species, such as tuna, at a higher risk for mercury contamination. Cooking does not reduce the mercury content in fish.

Tuna Species and Mercury Concentrations

Not all canned tuna is created equal. The species used for canning can have a major impact on the final product's mercury levels. The primary types of canned tuna are light tuna and white (albacore) tuna. The key difference in mercury concentration comes down to the size and age of the fish.

Light Tuna: Often made from skipjack or tongol tuna, which are smaller and younger species. These fish accumulate less mercury than their larger counterparts. Canned light tuna has the lowest mercury concentration of all canned tuna options, making it a safer choice for frequent consumption.
White (Albacore) Tuna: Sourced from albacore tuna, a larger, longer-lived species. This results in a higher mercury concentration compared to light tuna. A typical serving of canned albacore can contain up to three times more mercury than canned light tuna.

It is important to note that while canned tuna generally has lower mercury levels than fresh or frozen tuna steaks (from larger species like bigeye) because the fish are smaller, variability can still exist from can to can, even within the same brand and type.

Health Risks of Mercury Exposure

While the nutritional benefits of seafood, including tuna's high protein and omega-3 fatty acid content, are well-documented, excessive mercury exposure carries significant health risks. Methylmercury is a neurotoxin that can cause damage to the nervous system and the brain over time as it accumulates in the body.

For most healthy adults consuming moderate amounts of light tuna, the risk is minimal. However, certain populations are particularly vulnerable to mercury's harmful effects:

Pregnant Women and Developing Fetuses: Mercury can cross the placenta and impact fetal brain and nervous system development. High exposure in utero can lead to developmental delays and neurological issues in the child.
Young Children: Like fetuses, young children are highly sensitive to mercury during their rapid brain development phase.
Frequent Consumers: Individuals who eat large amounts of high-mercury fish on a regular basis may risk a build-up of the toxin in their bodies over time, potentially leading to neurological symptoms like memory loss, tingling, and impaired coordination.

Comparison of Canned Tuna Types

To help consumers make the best choice, here is a comparison of mercury levels and recommended intake for the two main types of canned tuna, based on FDA guidelines.


Tuna Type	Mercury Level (Approx. ppm)	Recommended Servings (Adults)	Notes
Canned Light (Skipjack)	~0.126	2-3 servings (8-12 oz) per week	Lowest mercury level; often less expensive.
Canned White (Albacore)	~0.350	1 serving (4 oz) per week	Higher in omega-3s but also higher in mercury.

Strategies for Reducing Your Mercury Exposure

Making smart choices at the grocery store and in the kitchen can help you safely enjoy the nutritional benefits of canned tuna while minimizing mercury risks. Here are some effective strategies:

Choose the right species: Opt for canned light or skipjack tuna over albacore, as they are consistently lower in mercury.
Diversify your diet: Incorporate a variety of other low-mercury seafood into your diet, such as salmon, sardines, shrimp, and tilapia. This reduces your reliance on a single source and lowers your overall mercury intake.
Follow serving guidelines: Adhere to the FDA's recommended weekly serving limits, especially if you fall into a vulnerable category like pregnancy or childhood.
Consider brand differences: Some brands, like Safe Catch, test every fish for mercury content, offering stricter limits and potentially lower-risk options, though at a higher price point.
Check the packaging: Some companies are developing innovative solutions, such as active packaging infused with cysteine, that can help reduce mercury levels in the tuna meat before it even reaches the consumer. Look for information on packaging or check the brand's website.

The Verdict on Canned Tuna

Ultimately, canned tuna can be a valuable part of a nutritious diet, providing high-quality protein and beneficial omega-3 fatty acids. However, the risk of mercury exposure is real and requires an informed approach to consumption. The key takeaway is moderation and selection. By choosing canned light or skipjack tuna and balancing your seafood intake with other low-mercury options, you can enjoy this convenient and affordable food without excessive concern. For detailed information on seafood consumption for vulnerable populations, consult the FDA's official guidance.

Conclusion

In summary, the answer to "Can you get mercury from eating canned tuna?" is a qualified yes, but the risk is manageable. Consumers are advised to differentiate between the types of canned tuna available. By consistently choosing smaller, younger species like skipjack and being mindful of portion sizes and frequency, the average adult can safely enjoy canned tuna as part of a varied, healthy diet. Vulnerable groups, including pregnant women and young children, should follow stricter consumption guidelines to protect their developing nervous systems. The wealth of accessible, nutritious, low-mercury seafood options available means that enjoying the health benefits of a seafood-rich diet is both safe and achievable for everyone.

Frequently Asked Questions

Canned light tuna, which is typically made from skipjack or tongol, generally has the lowest mercury levels because it comes from smaller, younger fish.

The FDA recommends that most adults can safely consume 2 to 3 servings (8 to 12 ounces) of canned light tuna per week.

Yes, but they should be mindful of the type and quantity. The FDA suggests 2-3 servings of canned light tuna per week, while limiting canned albacore to just one serving per week due to higher mercury levels.

Mercury levels differ because larger, older predatory fish like albacore have more time to accumulate mercury through bioaccumulation than smaller, younger fish like skipjack.

Symptoms of chronic mercury poisoning can include impaired fine motor skills, memory loss, irritability, and changes to vision, hearing, and speech.

For most individuals, the nutritional benefits of canned tuna—including lean protein and omega-3s—outweigh the minimal mercury risks when consumed in moderation and adhering to type-specific guidelines.

Good low-mercury alternatives include salmon, sardines, shrimp, clams, and tilapia, which offer similar nutritional benefits with less mercury concern.