Understanding Mercury Contamination
Mercury is a naturally occurring element that can accumulate in fish and shellfish, a process known as biomagnification. When released into the environment, typically through industrial processes, mercury can transform into methylmercury, a highly toxic form. This methylmercury builds up in the fatty tissues of fish, with larger, older predatory fish higher on the food chain tending to have the highest concentrations. Tuna, especially large species like bigeye, is a common source of mercury exposure for humans, necessitating informed choices to limit intake.
The Mercury Difference by Species
One of the most significant factors influencing mercury levels is the tuna species. The size and lifespan of the fish directly correlate with how much mercury it accumulates over its life.
- Light/Skipjack Tuna: These are smaller, younger, and faster-growing tuna species. Consequently, they have lower mercury concentrations than their larger relatives. Most canned 'light' tuna is made from skipjack and is considered the 'best choice' by health authorities.
- Albacore Tuna: Also known as 'white' tuna, albacore is a larger species that lives longer than skipjack, resulting in higher mercury levels. Health guidance suggests limiting consumption of canned albacore compared to light tuna.
- Bigeye Tuna: Often used for sushi (ahi), bigeye tuna is a larger, longer-lived species with the highest mercury content among common tuna types. It is a 'choice to avoid' for sensitive populations.
What Brand of Tuna Has Less Mercury? A Brand Spotlight
While the species is a primary indicator, brand practices regarding sourcing and testing can also provide peace of mind for consumers seeking lower mercury options.
Safe Catch: The Individual Testing Advantage
Safe Catch has built its entire brand around providing the lowest mercury tuna possible by testing every single fish they process. They use a proprietary technology to test each tuna, rejecting any that do not meet their strict standards.
- Safe Catch Elite Wild Tuna is tested to a mercury limit 10 times stricter than the FDA's action limit for their Ahi Yellowfin and Elite Skipjack varieties.
- This approach removes the uncertainty of individual can variations, which have been noted in other brands.
Wild Planet: Sustainable Sourcing for Lower Mercury
Wild Planet sources its tuna exclusively from smaller, younger fish caught using sustainable pole-and-line or troll methods. By catching smaller, younger fish, they ensure lower mercury levels inherently present in the stock.
- Their Skipjack tuna averages 0.067 ppm, significantly lower than the FDA's action limit.
- They also engage in third-party mercury testing to verify their products' safety.
Conventional Brands: Bumble Bee, Chicken of the Sea, and StarKist
For these common supermarket brands, the mercury difference largely depends on the species in the can. Chunk Light (skipjack) varieties are the safer bet compared to Albacore. However, Consumer Reports testing has shown that some cans, even of 'light' tuna, can contain unexpectedly high levels of mercury due to a lack of individual fish testing.
Tuna Mercury Comparison Table
| Feature | Safe Catch | Wild Planet | Conventional Brands (Light) | Conventional Brands (Albacore) |
|---|---|---|---|---|
| Tuna Type | Elite (Skipjack), Ahi (Yellowfin) | Skipjack, Yellowfin, Albacore | Mostly Skipjack | Albacore |
| Sourcing Method | Sustainable, FAD-Free, tested | Pole-and-line, troll caught | Varies (often purse seine) | Varies (often purse seine) |
| Mercury Testing | Tests every single fish | Third-party tested, sources younger fish | Batch testing | Batch testing |
| Mercury Levels | Consistently lowest due to individual testing | Consistently low due to sourcing | Low on average, but with potential for unpredictable spikes | High on average, with high variability |
| Sensitive Populations | Approved for pregnant women by APA | Generally considered a good choice | Can be okay, but requires caution due to variability | Generally not recommended |
How to Choose the Healthiest Tuna
Here are a few actionable steps to help minimize your mercury intake from tuna:
- Prioritize Species: Always choose canned light (skipjack) tuna over albacore. Skipjack tuna is consistently lower in mercury due to its shorter lifespan and position in the food chain.
- Consider Individual Testing: If you are particularly concerned, brands like Safe Catch offer the highest level of assurance regarding mercury levels by testing every can.
- Opt for Sustainable Sourcing: Look for terms like 'pole-and-line caught' or 'troll-caught' on the label. These methods typically target smaller, younger fish with lower mercury content, as done by brands like Wild Planet.
- Read the FDA/EPA Guidance: Review the latest recommendations from the U.S. Food and Drug Administration (FDA) and Environmental Protection Agency (EPA) for guidance on safe fish consumption, particularly for pregnant women and children. This guide provides information on frequency and quantity.
- Vary Your Fish Intake: To reduce reliance on tuna and minimize exposure, incorporate a variety of other low-mercury seafoods like salmon, sardines, and shrimp into your diet.
Conclusion
When asking what brand of tuna has less mercury, the answer involves a combination of factors, but two brands stand out for their explicit efforts. Safe Catch offers maximum assurance through its unique, can-by-can testing process, while Wild Planet's commitment to smaller, sustainably caught fish results in inherently lower mercury content. For consumers purchasing conventional brands, opting for 'chunk light' over 'albacore' is the most effective strategy for reducing mercury intake. Ultimately, understanding the species and the brand's practices is key to making a safer, healthier choice for yourself and your family.
For more information on mercury levels in various fish, visit the Healthline guide on mercury in tuna, is this fish safe to eat?.
