Women who avoid eating fish during pregnancy over fears of mercury content could be doing their unborn child more harm than good, scientists believe. New research shows that essential nutrients in fish actually protect against the effects of mercury and can also improve children's eyesight and intellectual abilities.
The NHS currently warns that fish known to contain mercury, such as tuna, could damage a developing baby's nervous system. But due to current advice, many pregnant women stop eating fish completely just to be on the safe side.
Dr Jean Golding, co-author and Emeritus Professor of Paediatric and Perinatal Epidemiology at the University of Bristol, said: "The guidance for pregnancy should highlight ‘Eat at least two portions of fish a week, one of which should be oily’ – and omit all warnings that certain fish should not be eaten."
The researchers used two studies that looked at women's mercury levels during pregnancy and compared the results to how the child developed after birth. The first study focused on a population in the Seychelles, where most of the pregnant women were fish eaters, and the second looked at women from the south-west of England who ate much less fish.
Dr Caroline Taylor, Senior Research Fellow and co-author of the study, concluded: “We found that the mother’s mercury level during pregnancy is likely to have no adverse effect on the development of the child provided that the mother eats fish." Dr Taylor added: "If she did not eat fish, then there was some evidence that her mercury level could have a harmful effect on the child.
"This could be because of the benefits from the mix of essential nutrients that fish provides, including long-chain fatty acids, iodine, vitamin D and selenium.”
Dr Jean Golding said: “It is important that advisories from health professionals revise their advice warning against eating certain species of fish. There is no evidence of harm from these fish, but there is evidence from different countries that such advice can cause confusion in pregnant women."
