Tuna is a convenient and affordable source of protein for many, perfect for quick snacks and easy meals. However, enjoying tuna too frequently can pose potential health risks due to its mercury content. How Much Tuna Is Too Much? Let’s dive into the details with expert insights.
Tuna and Mercury: What You Need to Know
Tuna contains methylmercury, a type of organic mercury. “Methylmercury is typically absorbed by the gastrointestinal tract and then distributed to different parts of the body, especially the nervous system and brain,” explains Dr. Michael O’Neill, an internal medicine specialist at Hartford HealthCare Medical Group. “Consuming excessive mercury can lead to symptoms of chronic mercury poisoning.”
These symptoms may include:
- Memory loss
- Irritability
- Tingling sensations
- Changes in taste, vision, and smell
While treatments exist to help remove mercury from the body, Dr. O’Neill emphasizes that “the best treatment is usually just to avoid unnecessary mercury exposure. Unfortunately, it can take weeks or even months for mercury to leave the body.”
Canned tuna on a shelf, highlighting the importance of reading labels and understanding mercury content.
How Much Tuna Can You Safely Eat?
Moderation is key when it comes to tuna consumption. According to the FDA, adults can generally consume six to nine ounces of tuna per week safely. “That typically works out to one to two cans, depending on the size,” Dr. O’Neill notes.
However, some individuals need to be more cautious:
- Children and low-weight adults: Should consume even less tuna.
- Pregnant or breastfeeding mothers: Should avoid tuna altogether.
If you’re a frequent tuna eater, consider diversifying your protein sources with options like salmon or cod, which contain significantly less mercury.
Mercury Levels Vary in Different Tuna Types
It’s crucial to check the label before purchasing tuna, as mercury levels differ depending on the species. Smaller tuna generally accumulate less mercury, making some brands safer than others.
- Canned Light/Chunk Light (Skipjack): Contains approximately 20 micrograms of mercury per five-ounce can.
- Albacore and Yellowfin: Can contain up to 50 micrograms of mercury per can.
- Atlantic Bluefin: The largest tuna species, can contain as much as 283 micrograms of mercury per five ounces.
Choosing tuna made from smaller fish species like Skipjack is a practical step in minimizing mercury intake without completely eliminating tuna from your diet.
Sourcing Matters: Where and How Your Tuna is Caught
When buying tuna, consider the source and fishing methods. Dr. O’Neill advises, “Trustworthy companies will be transparent about where the fish was caught. Try to buy tuna caught from local or U.S. fisheries, as they tend to be in better health.” Avoid tuna with unclear origins, particularly those caught in the Indian Ocean.
Look for labels indicating sustainable fishing practices:
- Line caught
- Pole caught
- FAD (fish aggregating device) free
These methods are more environmentally responsible and safer for other marine life.
The Bottom Line: Enjoy Tuna Responsibly
While tuna is a convenient and nutritious food, it’s essential to be mindful of mercury levels and consume it in moderation. By understanding the different types of tuna, choosing sustainable sources, and following recommended consumption guidelines, you can enjoy the benefits of tuna while minimizing potential health risks. If you have concerns about your mercury intake, consult with a healthcare professional.
