Mackerel

Mackerel is safe and nutritious but should be limited to two portions of oily fish per week in total. Avoid smoked mackerel eaten cold — it should be heated until hot.

Eat with caution

Mackerel is one of the most nutritious fish available — it is exceptionally rich in omega-3 fatty acids, vitamin D, vitamin B12, and selenium, all of which are important during pregnancy. However, as an oily fish, it can accumulate environmental pollutants such as PCBs and dioxins. For this reason, the NHS advises pregnant women to limit total oily fish consumption to no more than two portions per week across all varieties (salmon, sardines, trout, mackerel, herring, and pilchards). Fresh mackerel cooked thoroughly is safe within this limit. Smoked mackerel is commonly sold ready-to-eat and cold in supermarkets — this cold-smoked or lightly-cured product carries a risk of Listeria and should ideally be heated until piping hot before eating during pregnancy, or avoided. King mackerel — a larger, unrelated species — is much higher in mercury and should be avoided entirely during pregnancy (see the swordfish article), but the common Atlantic mackerel widely available in UK shops is safe within the two-portion limit.

What to be aware of

Limit oily fish to two portions per week total — count mackerel alongside salmon, trout, sardines, and herring.
Heat cold-smoked mackerel until piping hot before eating in pregnancy, or choose freshly cooked mackerel instead.
King mackerel (a different, tropical species) is high in mercury and should be avoided — this is different from the common Atlantic mackerel sold in UK shops.
Fresh mackerel must be very fresh as it deteriorates quickly — it should smell like the sea, not 'fishy'.

NHS guidance: https://www.nhs.uk/pregnancy/keeping-well/foods-to-avoid/

US guidance

The FDA classifies Atlantic mackerel as a 'best choice' fish (up to 2–3 servings per week) due to its low mercury content. However, they advise avoiding King mackerel entirely due to high mercury. The NHS approach focuses on oily fish as a category and limits intake due to pollutants rather than mercury specifically.

Pregnancy-safe recipes

These recipes are designed with pregnancy safety in mind.

Grilled mackerel with gooseberry sauce

Classic British grilled mackerel served with a sharp, fruity sauce — the acidity cuts through the rich oily fish perfectly.

Pregnancy tip: Mackerel cooks quickly under a hot grill — the skin should be crisp and the flesh completely opaque. Score the skin before grilling to prevent curling.

Ingredients

2 whole mackerel, gutted and cleaned (or 4 fillets)
200g gooseberries (or use jarred)
1 tbsp sugar
1 tbsp butter
Salt and pepper
Lemon to serve

Method

Score the mackerel skin 3–4 times on each side. Season with salt and pepper.
Place under a preheated grill on high, 10–12cm from the heat.
Grill for 5–6 minutes each side until the skin is crisp and flesh completely opaque.
Meanwhile, cook gooseberries with sugar and a splash of water until soft. Stir in butter.
Serve the mackerel with the warm gooseberry sauce and lemon.