Fish for babies: when, how, and the mercury rules
Fish is one of the best early foods there is: loaded with protein and the omega-3 fats that help build a growing brain. It is also a common allergen and carries the one real catch, mercury. Here is how to give it early, often, and safely.
Introduce it early
From around 6 months, fish is a great allergen to offer, and offering it early and regularly is linked to a lower chance of a fish allergy developing. Fish is a separate allergen from shellfish, so being fine with one says nothing about the other. See introducing allergens and shellfish for babies.
The mercury rule: choose low, skip high
Good low-mercury choices: salmon, cod, tilapia, trout, sardines, and canned light tuna.
Avoid entirely (high mercury): shark, swordfish, king mackerel, marlin, orange roughy, tilefish, and bigeye tuna. The rule of thumb: small fish, low mercury; big long-lived predators, high mercury.
What about canned tuna?
Fine in moderation with the right can. Canned light tuna (skipjack) is lower in mercury than white or albacore, so it is the one to reach for, about once a week in small amounts. Choose no-salt-added or rinse it, mash it well, and check for stray bones. This is exactly the "feeding baby canned tuna" question, and the answer is yes, with care.
How to serve it
Cook it through (no raw fish or sushi for babies), flake it, and go over it carefully to remove every bone. Stir the soft flakes into a purée or mash, or offer larger soft pieces for baby-led weaning. Keep it plain.
Related reading
See shellfish for babies, iron-rich first foods, and signs of a food allergy.
This is general information, not medical advice. Follow current local advice on fish and mercury during the first years, remove all bones, and talk to your pediatrician about any reaction or if there is a family history of fish allergy.
Frequently asked questions
When can babies have fish?
From around 6 months. Fish is one of the common allergens, and current guidance is to introduce it early and regularly rather than delay it. It is also a genuinely great early food: rich in protein and the omega-3 fats that support brain and eye development.
Is canned tuna safe for babies?
In moderation, yes, if you choose the right kind. Canned light tuna (skipjack) is lower in mercury than white or albacore tuna, so it is the better pick and can be offered about once a week in small amounts. Buy no-salt-added or rinse it, mash it well, and check carefully for any tiny bones.
Which fish are low in mercury, and which should I avoid?
Good low-mercury choices include salmon, cod, tilapia, trout, sardines, and canned light tuna. Avoid the high-mercury fish entirely: shark, swordfish, king mackerel, marlin, orange roughy, tilefish, and bigeye tuna. When in doubt, smaller fish are generally lower in mercury than big predators.
How do I prepare fish for a baby?
Cook it thoroughly (no raw fish or sushi), then flake it and go through it carefully to remove every bone. Mix the soft flakes into a purée or mashed potato, or offer larger soft pieces for baby-led weaning. Keep it plain, no added salt.
Track it in Yummy Yucky
Log first tries, get nudged through the 3-day allergen watch, and keep every bite in one place you can share with your pediatrician.
Start tracking for freeHow we write these: from widely published pediatric guidance (AAP, NIAID 2017 guidelines, the LEAP study), with sources cited on every page. Pending review by a pediatric professional.
This is general information, not medical advice, and has not been individually reviewed for your baby. Always talk to your pediatrician about your baby's diet, introducing allergens, and any reaction. In an emergency, contact emergency services.
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