Is 160g of Tuna Too Much? Understanding Mercury and Moderation

December 14, 2025 •

4 min read

According to the FDA, adults should aim for 2–3 servings of fish per week for essential nutrients like omega-3s, but this comes with important considerations, especially regarding tuna's mercury content. So, is 160g of tuna too much, and how does this fit into a balanced diet?

Quick Summary

This article explores the safety of consuming 160g of tuna, focusing on weekly recommendations, mercury levels in different tuna types, and important health considerations for adults, children, and pregnant individuals.

Key Points

Moderate Consumption: A single 160g serving of canned light tuna is generally safe for adults as part of a balanced diet.
Albacore vs. Light Tuna: Canned albacore (white) tuna has significantly higher mercury levels than canned light (skipjack) tuna, and weekly limits for albacore are much stricter.
FDA Guidelines: The FDA suggests adults consume 2-3 servings (8-12 ounces) of low-mercury fish, including light tuna, per week.
Pregnant and Children: Vulnerable populations should be especially cautious, limiting intake and prioritizing lower-mercury fish options due to developmental risks.
Dietary Diversity: To minimize mercury risk and ensure broad nutrient intake, it is best to diversify your protein sources rather than relying solely on tuna.
Long-term Effects: Chronic, high intake of mercury from fish can have cumulative effects on the body, affecting the nervous system.

Understanding the Mercury Risk in Tuna

Mercury is a naturally occurring element that is present in the environment and accumulates in fish, including tuna. The amount of mercury depends on the size and type of tuna, as larger, older fish tend to have higher concentrations. Consuming excessive amounts of mercury can pose health risks, particularly affecting the central nervous system.

The most common canned tunas are light tuna (typically skipjack) and albacore (white) tuna. Light tuna usually comes from smaller, younger fish and thus contains lower levels of mercury. Albacore, on the other hand, comes from larger fish and can have up to three times the mercury content of light tuna. This distinction is crucial when evaluating if 160g of tuna is too much for your weekly intake.

Official Guidelines for Tuna Consumption

Health organizations provide clear guidance on safe fish intake. For instance, the FDA recommends adults eat 8 to 12 ounces (227 to 340 grams) of low-mercury fish per week, including canned light tuna. However, for canned albacore, which is higher in mercury, the recommendation is to limit intake to one 4-ounce (113-gram) serving per week.

Canned Light Tuna: Generally safe for 2–3 servings per week (equivalent to 160g being safe for a single weekly meal).
Canned Albacore Tuna: Recommended limit of 4 ounces (approx. 113g) per week, making 160g potentially excessive for a single week.
Pregnant and Breastfeeding Women: Advised to consume 2–3 servings (4 ounces each) of low-mercury fish like canned light tuna per week, while limiting albacore to no more than 4 ounces per week.
Children: Recommendations vary by age, but intake is more restricted due to their developing nervous systems.

160g of Tuna: Is it a Safe Amount?

A 160g serving, which is common in many single-serve tuna pouches or small cans, falls within the recommended portion size for a single meal. However, whether it's 'too much' depends on the type of tuna and your total weekly intake. For canned light tuna, a 160g portion is perfectly acceptable as one of your 2-3 weekly servings. For albacore, a 160g portion would exceed the recommended weekly limit, so it should be consumed less frequently.

The Importance of Variety in Your Diet

While tuna offers significant health benefits, relying solely on it for protein can lead to excessive mercury accumulation. Experts recommend diversifying your protein and fish sources to balance nutrient intake and minimize mercury exposure. Incorporating other seafood like salmon, cod, or crab, which are lower in mercury, is a smart strategy. This variety also ensures a wider range of vitamins and minerals in your diet. The Australian Broadcasting Corporation (ABC) conducted lab tests suggesting you'd need to consume between 25 and 35 small tins (95g each) of light tuna a week before reaching maximum mercury limits, but this high volume is unnecessary and neglects the importance of dietary variety.

Comparison: Light Tuna vs. Albacore (Per 160g Serving)


Feature	Canned Light Tuna (Skipjack)	Canned Albacore Tuna (White)
Mercury Content	Lower levels	Higher levels (up to 3x more)
Weekly Intake	Can be consumed 2–3 times per week	Limit to one 113g (4 oz) serving per week
Protein per 160g	High (Approx. 40–50g)	High (Approx. 40–50g)
Omega-3s	Good source	Good source
Flavor	Stronger, more fishy flavor	Milder, more delicate flavor

Potential Health Risks of Excessive Tuna Consumption

Beyond the mercury concern, excessively high intake of any single food can lead to nutritional imbalances. In extreme cases, chronic mercury toxicity can impact neurological function, causing symptoms like anxiety, depression, and poor motor skills. These are typically associated with very high, long-term consumption, not a single 160g serving. However, the cumulative effect of regular high-mercury tuna intake is the primary concern that informs official dietary guidelines.

Conclusion: Moderation is Key

In summary, whether 160g of tuna is too much depends on the type of tuna and your overall weekly consumption. A single 160g serving of canned light tuna is generally safe as part of a balanced diet. If you choose albacore, that same portion would exceed the standard weekly recommendation. The key is moderation and dietary diversity. By understanding the mercury content of different tuna types and following health authority guidelines, you can safely enjoy tuna's nutritional benefits without undue risk. As with any dietary choice, it's always best to balance your intake and consult with a healthcare provider if you have specific health concerns.

Supporting Research

In addition to official guidelines, ongoing research highlights the need for informed dietary choices. A 2015 Consumer Reports analysis found varying mercury levels even within the same brand of canned tuna, reinforcing the need for caution, especially with higher-mercury albacore. A 2022 article from The Conversation discussed lab tests showing that many cans of light tuna fall well within safe mercury limits for moderate consumption, suggesting it's the quantity and type that matters. This body of evidence supports the recommendations for moderation and smart choices when it comes to eating tuna.

Frequently Asked Questions

For low-mercury canned light tuna (skipjack), the FDA recommends 2–3 servings (8–12 ounces or 227–340 grams) per week. For higher-mercury canned albacore, it is recommended to limit intake to one 4-ounce (113-gram) serving per week.

Canned light tuna, primarily made from skipjack, contains significantly lower levels of mercury than canned albacore (white) tuna. Albacore can contain up to three times more mercury than light tuna.

Yes, canned tuna generally has lower mercury levels than fresh or frozen tuna steaks. This is because canned tuna uses smaller, younger fish (like skipjack), while larger, older fish (like bigeye or some albacore) with higher mercury are used for fresh cuts.

While unlikely from moderate intake, consistently consuming excessive amounts of high-mercury tuna over a long period can lead to mercury accumulation in the body, potentially causing health issues like neurological problems.

Yes, 160g of tuna would likely be too much for a child in a single meal or week. Health recommendations for children are much stricter, with European guidelines suggesting a max of 140g per week for older children and less for younger ones.

Excellent low-mercury seafood options include salmon, cod, shrimp, sardines, and clams. Varying your fish intake helps balance nutrients and reduce mercury exposure.

No, pregnant and breastfeeding women do not need to avoid tuna completely. The FDA recommends they consume 2–3 servings (4 oz each) of low-mercury light tuna per week while limiting albacore to no more than 4 ounces per week.