Latest advice to pregnant and breastfeeding women on eating certain fish

Pregnant and breastfeeding women, and those who intend to become pregnant, should eat no more that two medium-sized cans of tuna, or one fresh tuna steak per week, according to the updated Food Standards Agency advice. These women were also advised to eating shark, swordfish and marlin. This is because mercury can harm an unborn child's developing nervous system.

This precautionary advice is being issue to protect against the small risk to the unborn child, and breast-fed babies, from mercury in certain fish. It follows an extensive review by the independent Committee on Toxicity (COT) on the possible risks. The new safety guideline for pregnant and breastfeeding women intending to become pregnant is almost five times lower than that for the general population.

This new advice on tuna does not apply to children or other adults. However, infants and children under 16 are still advised to avoid eating shark, swordfish and marlin. Shark, swordfish and marlin have levels of mercury approximately 5-7 times higher than that of canned tuna and 2-4 times higher than that of fresh tuna.

Fish remains an important part of a balanced diet. It is a good source of high quality protein and other nutrients; it is low in fat and oily fish can help prevent death from heart attack. Because of these benefits, fish is also an important part of a balanced diet for pregnant women. The Food Standards Agency's general advice on fish consumption is to eat two portions of fish a week, one of which should be oily, as part of a balanced and varied diets.