The 6 fish you should never eat while pregnant (and the ones that are fine)

Fish to avoid entirely during pregnancy

• Shark
• Swordfish
• King mackerel
• Tilefish (Gulf of Mexico)
• Bigeye tuna (ahi)
• Marlin

These are apex predators — they accumulate methylmercury from smaller fish over decades. Methylmercury crosses the placenta and affects foetal brain development.

Limit, don't eliminate

Canned/chunk light tuna — fine in moderation. UK NHS: up to 4 medium cans / 2 fresh tuna steaks per week. US FDA: similar.

Albacore ("white") tuna — higher mercury. One serving per week max.

Halibut, sea bass, grouper, marlin — occasional, not weekly.

Genuinely safe and beneficial

• Salmon (wild preferable, farmed fine if from reputable supply)
• Sardines
• Cod, haddock, plaice
• Trout
• Anchovies
• Mackerel (Atlantic, not king)

These are the foundation of "eat 2–3 portions of fish per week" pregnancy advice. Omega-3 from these actively supports foetal brain development.

Why the NHS and FDA slightly disagree NHS is more cautious on tuna (4 cans/week). FDA allows a bit more. This reflects population-level caution vs. US statistical modelling. Either way: moderate is the rule.

Other seafood rules

• No raw fish (sushi from already-frozen ingredients is a grey area — most hospitals say avoid)
• No smoked salmon, lox, or gravadlax — listeria risk
• No pâté, including fish pâté — listeria risk
• Cooked shellfish only — prawns, crab, lobster fine if hot

How EggYolk handles it When you set your profile to "Pregnancy", scanning a tuna product, a smoked salmon pack, or a tin of sardines returns different verdicts — we filter by category automatically. No manual checking.

Sources: NHS pregnancy advice, FDA/EPA mercury guidance, EFSA fish consumption recommendations. Not medical advice — consult your midwife or OB.