Food · Avoid

Absolutely avoid

Biggest risk at the top. One line each.

This whole page was written out of three vault files: Absolutely avoid: the aisle cardFoods: the full reasoningSupplements and herbs

The one-screen version

If you read nothing else in the aisle, read this.

Five things with real evidence of harm, no negotiation:

  1. Liver, liver pâté, liver sausage, faggots, cod liver oil: retinol
  2. Shark, swordfish, marlin: mercury
  3. Alcohol: fetal alcohol spectrum disorder
  4. Liquorice, in sweets, tea or root form: glycyrrhizin
  5. Game shot with lead ammunition: lead

Three that are precautionary, but where the downside is catastrophic:

  1. Pâté of any kind: meat, fish and vegetable
  2. Mould-ripened and soft blue cheese, uncooked
  3. Cold-smoked salmon, trout and gravlax; raw-fish sushi

Two numbers: caffeine no more than 200 mg a day · tuna no more than four medium cans, or two fresh steaks, a week.

Read the evidence: Absolutely avoid: the aisle card

Know which is which. harm means there is documented human evidence of harm. Everything unmarked is a precaution: no demonstrated harm at realistic exposure, but the downside is severe, the data thin, or avoidance cheap. Most of this page is precaution. Only the six items in the first block are harm.

The tier tag next to each line is a separate question: how good the evidence is, rather than what it shows. Select one to see what it means, or read the evidence hierarchy.

Tier 1: real evidence of harm

No exceptions, no cooking workaround.

Tier 2 listeria: avoid it, or cook it

None of these are forbidden forever. Cooking until steaming hot makes almost all of them fine.

Tier 2 toxoplasma and salmonella: cook it through

throughout. This block is NHS and Food Standards Agency guidance rather than primary evidence.

Tier 3: handle carefully rather than avoid

This is where UK listeria cases actually cluster, far more than in the famous cheeses. It gets a fraction of the airtime.

Pre-packed sandwiches, wraps and salads with meat, fish, egg or dairyKeep chilled, eat well before the use-by, never leave in a warm bag or a hot car. A long chilled shelf life plus ready to eat plus no kill step is listeria’s niche.
Bagged salad leaves labelled washed and ready to eatWash them anyway. Keep them cold.
Pre-cut fruit pots, especially melonKeep chilled, eat promptly.
Deli-counter and prepared saladsSame rules: chilled, in date, eaten early.
Cold cooked sliced meats: ham, cooked chickenFine in UK guidance if properly chilled and in date. American advice says microwave all deli meat; that is not the UK position.
Pre-cooked chilled prawnsFine. Keep properly chilled, eat within the use-by.
Soft-serve ice cream from machinesNot banned if the mix is pasteurised, but a poorly maintained machine is a known listeria vector. A judgement call.
Hot-smoked salmon in a ready-to-eat packGrey area: logically outside the cold-smoked rule, but the UKHSA page does not distinguish hot from cold. Safest is to heat it until steaming.

Read the evidence: Absolutely avoid: the aisle cardFoods: the full reasoning

The limits: numbers, not bans

ItemLimitWhyEvidence
Caffeine200 mg a day, all sourcesCounts coffee, tea, green tea, matcha, cola, energy drinks, chocolate, guarana and some cold and flu remedies. A single high-street milky coffee can be the whole day’s allowance. Independent testing measured 325 mg in one chain’s medium cappuccino. Assume 150-250 mg unless you know the chain.Read the evidence · Foods: the full reasoning
Tinned tuna4 medium cans a weekMercury. Canned tuna is smaller, younger fish, and it does not count toward the oily-fish allowance.Read the evidence · Foods: the full reasoning
Fresh tuna steak2 steaks a weekMercury.Read the evidence · Foods: the full reasoning
Oily fish: salmon, trout, mackerel, sardines, herring, fresh tuna2 portions a week, and this is a target, not just a ceilingDioxins accumulate over a lifetime, but oily fish is the main source of DHA for the baby’s brain and retina, and UK women systematically eat too little of it.Read the evidence · Absolutely avoid: the aisle card
Herbal tea4 cups a dayA genuinely obscure NHS limit that catches people who quit coffee and now drink eight herbal teas.Read the evidence · Supplements and herbs
Vitamin A supplementsNone containing retinolSee the top of this page.Read the evidence · Supplements and herbs

Actually fine: stop worrying

Every item below is commonly over-avoided. Each one is a real permission from UK guidance, not a technicality. throughout.

  • Runny and raw eggs: soft-boiled, poached, fried wet, homemade mayonnaise, mousse, tiramisu, hollandaiseIf stamped with the red British Lion mark, or “Laid in Britain”. The FSA reversed decades of advice in October 2017, and over ninety per cent of UK eggs carry the mark. American advice still bans runny eggs because the US has no equivalent scheme.
  • Hard cheese, including unpasteurisedCheddar, parmesan, pecorino, gruyère, manchego, comté. Yes, unpasteurised parmesan is fine. UK rules turn on moisture and acidity, not pasteurisation. This is the exact opposite of American advice.
  • Pasteurised soft cheeses with no rind or mouldCottage cheese, cream cheese, mozzarella, feta, paneer, ricotta, mascarpone, halloumi, burrata, cheese spreads and triangles.
  • Any soft cheese cooked until steaming hotBaked camembert, brie in a toastie, blue cheese melted into a sauce. Cooking kills listeria.
  • Cooked shellfish: prawns, crab, lobster, squid, mussels, scallops, clamsAll fine cooked, including pre-cooked chilled prawns, kept cold and in date.
  • Cooked sushi: prawn, crab stick, tamago, unagi, avocado, cucumber, cooked salmonFine. It is the raw fish that is restricted, not the sushi.
  • Peanuts and all nutsEat freely unless she is allergic. The old avoidance advice was withdrawn and reversed. Restricting them does not prevent childhood allergy.
  • HoneyFine in pregnancy. The infant-botulism restriction applies to babies under one year, not to pregnancy. Very commonly confused.
  • Cold cooked sliced meats: ham, cooked chicken from a packFine, chilled and in date. UK advice is more relaxed than American advice here.
  • Pepperoni on a cooked pizzaIt has been in an oven. Fine.
  • Tinned smoked fishRetort-processed at high temperature. Fine.
  • Normal warm bathsFine. The concern is raising core temperature, not bathing. It is saunas, hot tubs, very hot baths and long hot showers that are the issue. A normal bath is also one of the more effective things available for back pain and sleep. Heat is a vasodilator, so get out slowly and sit down to dry off.
  • Decaffeinated coffee and teaNot zero caffeine, but trivially low.
  • A slice of brie or a glass of wine before she knew she was pregnantThe absolute risk of listeriosis is on the order of one in fifteen to twenty thousand pregnancies, and the NHS position on alcohol before knowing is that a small amount does not mean harm has occurred. Mention it at booking. Do not catastrophise it.

Read the evidence: Foods: the full reasoningAbsolutely avoid: the aisle card

Two mental models that replace memorising this page

  1. Cook it and it is fine. That covers almost the entire listeria list: baked camembert, hot smoked-salmon pasta, pepperoni pizza, cooked cured meat.
  2. The risk lives in chilled, ready-to-eat, long-shelf-life food. Hot food cooked to order is essentially never the problem. That single sentence beats the cheese list for real-world protection.

Practical Two heuristics for remembering the list, not claims in their own right. The evidence they compress is in Foods: the full reasoning.

And one framing worth keeping

There were about 179 listeriosis cases in England and Wales in 2024, roughly a fifth of them pregnancy-associated, against about 600,000 births. The rules exist because when it happens the outcome is very bad, not because the food is likely to hurt the baby. That is a rational trade at one in fifteen thousand, and it is not a reason to panic about something already eaten.

Read the evidence: Absolutely avoid: the aisle card

Also on the avoid list, but not food

A scannable version of NHS guidance, not a replacement for it. Last reviewed against the NHS foods-to-avoid page of 15 June 2026.

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