Fish and Mercury Levels

Fish and Mercury: A Guide for Parents on Feeding Babies

Introducing fish into your baby’s diet can be incredibly beneficial, offering essential nutrients like omega-3 fatty acids, protein, and vitamins D and B12. However, the presence of mercury in some fish raises valid concerns, especially for infants and young children. This article will guide you on the safe consumption of fish for babies, helping you balance the nutritional benefits while minimizing mercury exposure.

Understanding Mercury in Fish

Mercury is a naturally occurring element found in air, water, and soil. It exists in several forms, with methylmercury being the most common type found in fish. Methylmercury accumulates in water bodies and works its way up the food chain, meaning larger, predatory fish tend to have higher levels. High mercury levels in a baby’s diet can potentially affect their developing nervous system, leading to cognitive, motor, and sensory impairments.

Why Fish is Important for Babies

Despite concerns about mercury, fish is an excellent source of essential nutrients that contribute to a baby’s growth and development. Omega-3 fatty acids, particularly DHA (docosahexaenoic acid), are crucial for brain development. Additionally, fish provides high-quality protein, necessary for muscle and tissue growth, and vitamins that support overall health.

Safe Fish Choices for Babies

When introducing fish to your baby’s diet, the key is to choose varieties that are low in mercury but still rich in nutrients. Some of the best options include:

• Salmon: A great source of omega-3 fatty acids, low in mercury. Canned salmon is budget friendly and can often get the wild caught red salmon variety for a budget friendly price.
• Sardines: Packed with nutrients, including calcium, protein and omega-3s, with minimal mercury. Canned sardines are also a fantastic pantry staple that provides an abundance of omega 3-s and calcium. Canned sardines are often better because the bones are soft to offer to your baby. Extra calcium!
• Trout: Another low-mercury option, providing a good source of omega-3s.
• Atlantic mackerel: High in nutrients and low in mercury, making it a safe choice. Atlantic mackerel is the variety you find in canned mackerel at the supermarket in Australia.
• Pollock: Often used in fish sticks, this is a low-mercury fish suitable for babies.
• Snapper
• John Dory
• Flathead: this is a very flaky fish however may sometimes have bones.
• Atlantic cod
• Whiting
• Flounder

Other low mercury sources of seafood:

• Prawns
• Oysters
• Bugs
• Crab

On the other hand, certain fish should be avoided or consumed sparingly due to their higher mercury content. These include:

• Shark (also known as flake)
• Swordfish
• King Mackerel
• Orange roughy 
• Bigeye Tuna
• Barramundi
• Gemfish
• Ling

These fish accumulate more mercury because they are higher up the food chain and live longer, giving them more time to build up mercury in their bodies.

How Much Fish Should I Offer My Baby?

Australian guidelines suggest offering children under 2 years old two to three servings of low-mercury fish each week, with a serving size of 50g. For adults, the recommended portion is 150g, and for children under 6 years, it’s 75g per serving. This approach ensures that young children can benefit from the nutrients in fish while minimizing their exposure to mercury.

Preparing Fish for Babies

When preparing fish for your baby, ensure it is fully cooked to eliminate any harmful bacteria. Flake the fish to check for bones before serving, and consider mashing or pureeing it for younger babies from 6 to 9 months. Pairing fish with vegetables, grains, or other nutrient-rich foods can make meals more balanced and enjoyable for your little one.

Signs of Mercury Exposure

While the likelihood of mercury poisoning from fish consumption is low when following safe guidelines, it’s important to be aware of the symptoms of mercury exposure. These may include:

• Delays in cognitive development
• Motor skill difficulties
• Speech and language delays
• Impaired coordination and balance

If you have concerns about mercury exposure, consult with a healthcare professional to ensure your baby’s diet is safe and healthy.

What About Canned Tuna?

Debate exists about the mercury levels in canned tuna, with differences arising internationally because of the various tuna species used, brand diversity, and the extent of mercury testing by countries. Australian regulations, as per Food Standards Australia New Zealand (FSANZ), affirm that canned tuna is safe for all, including pregnant women and children, allowing for a 95g daily consumption without other fish. Different tuna species, like Skipjack and Yellowfin—common in Australian tinned tuna—vary in size and mercury content. For children under two, opt for Skipjack tuna, limiting servings to 50g, and prioritise fish lower in mercury and rich in omega-3 for broader nutritional benefits. Ideally the tuna species that has lower mercury levels overall is Skipjack and goes by the scientific name Katsuwonus Pelamis if you’re confirming the correct species of tuna on the back of a nutrition label.

Conclusion

Fish can be a valuable addition to your baby’s diet, providing essential nutrients that support growth and development. By choosing low-mercury fish and sticking to recommended serving sizes, you can help your baby reap the benefits of fish while minimizing the risks associated with mercury. As always, if you’re unsure or need personalized advice, consult with a pediatrician or a nutritionist who can guide you through the process.

Support and Resources

Navigating the world of infant nutrition can be challenging, but you don’t have to do it alone. Joining a supportive online community can provide access to shared experiences, expert advice, and a space to ask questions about your baby’s diet, including concerns about fish consumption and mercury. Our Mum Bub Membership offers a community with a wealth of information and a comforting environment where parents can feel confident in their choices. Join the Mum Bub Membership for as little at $10 a month here 

References:

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2. Grandjean P. Methylmercury toxicity and functional programming. Reprod Toxicol. 2007 Apr-May;23(3):414-20. doi: 10.1016/j.reprotox.2007.03.002. Epub 2007 Mar 12. PMID: 17408921.
3. Bose-O’Reilly S, McCarty KM, Steckling N, Lettmeier B. Mercury exposure and children’s health. Curr Probl Pediatr Adolesc Health Care. 2010 Sep;40(8):186-215. doi: 10.1016/j.cppeds.2010.07.002. PMID: 20816346; PMCID: PMC3096006.
4. Dragan F, Lestyan M, Lupu VV, Marcu FM, Cozma A, Fodor K, Ciubara A, Moisa CF, Teaha D, Lupu A, et al. The Threat of Mercury Poisoning by Fish Consumption. Applied Sciences. 2023; 13(1):369. https://doi.org/10.3390/app1301036
5. John Sumner and Cath McLeod, Seafood Consumption in Australia: Risks and Benefits, June 2015, Australian Government: Fisheries Research and Development Corporation.
6. Food Standards Australia New Zealand, Mercury in fish, foodstandards.gov.au, 2020, accessed on 27th August 2024.