Pregnant Women Urged to Eat More Fish

Experts call for an urgent update of official guidelines on fish and seafood in pregnancy, as new study of 300,000 mother–child pairs finds better brain development scores in children whose mothers eat more fish during pregnancy - and NO evidence of harm.

This new research, published in Neurotoxicology, finds that when pregnant women cut back on fish, their children may be missing out on vital nutrients - including long chain omega-3 fatty acids - that are essential for building healthy brains and eyes.

The impressive authorship list includes several FAB speakers and connections including the renowned Professor Michael Crawford, Dr Joseph Hibbeln, Dr Tom Brenna, Professor Susan Carlson and Professor Jean Golding, as well as many other leading researchers in the field, including first author Dr Philip Spiller, whose expertise and experience includes 35 years working for the U.S. Food and Drug Administration in this area.



For years, U.S. federal advisories have urged women to limit fish consumption during pregnancy because of concerns about mercury. But according to the research team, evidence shows that the benefits of eating fish far outweigh the risks - particularly for ocean fish species commonly available in supermarkets.

Ocean fish, in particular, contain a balance of nutrients - including selenium - that protect against mercury’s effects.

The researchers reviewed decades of studies and found “considerable evidence of improvements and little evidence of harm” when mothers ate more fish during pregnancy.

The greatest gains came when women ate 8–12 ounces per week - yet most U.S. women eat far less, reducing fish in their diets or avoiding fish entirely once they become pregnant, fearing harm to their child.

The same dietary patterns are clear in the UK, and likely to be worsened by messaging from our National Health Service, in which:

1. Fish is primarily positioned as a source of protein or 'toxins' - rather than a nutritious package of brain-essential nutrients - including omega-3 DHA, iodine, zinc, choline and selenium, among many others. And importantly, there is evidence that the selenium found in ocean fish actually protects against possible toxic effects of mercury.
2. Pregnant women are told to limit consumption to no more than 2 portions of oily fish a week - despite the evidence for better cognitive development in children whose mothers consume more fish and seafood than this.

Outdated Advisories are not Evidence-Based

The authors of this paper point to the U.S. advisories issued since 2001 which urged pregnant women to limit fish to no more than 12 ounces per week, out of caution about mercury exposure. But those limits were set before today’s wealth of evidence and were not based on actual studies of fish consumption.

FAB Research are in agreement with the authors, who urge health agencies to

• update official fish consumption guidelines to reflect the latest science, and
• launch public education campaigns that encourage rather than discourage fish consumption during pregnancy. Such changes could lead to population-wide gains in children’s cognitive and brain development.

A Serious Public Health Issue

This is a serious public health issue as, by following outdated advisories, millions of families may be missing out on a safe, simple way to give their children a brain development advantage.

What's more, insufficient intakes of the special omega-3 in fish & seafood (specifically - the long-chain omega 3 DHA) are also a known risk factor for pre-term birth.

• gold-standard evidence from randomised controlled trials shows increased intakes of the omega-3 found in fish oils can significantly reduce pre-term birth (although this evidence currently remains ignored in NHS and NICE guidelines for pregnancy).

Evidence-based public health campaigns across the globe which encourage fish consumption during pregnancy could not only help improve childhood cognitive outcomes and support healthy development, but could also reduce the major and costly risks associated with low maternal omega-3 intake, including pre-term birth.

For more on Omega-3 and Pre-term Birth:

See FAB's Article and Downloadable Handout on Omega-3 in Pregnancy for Pre-term Birth - which references:

• The Cochrane systematic review & meta-analysis of 70 RCTs involving almost 20,000 women, showing that supplementing pregnant women with omega-3 LC-PUFA reduces pre-term birth (Middleton et al 2018).
• The Consensus statement from ISSFAL reporting that there is good evidence to support the use of omega-3 during pregnancy to prevent pre-term birth (Best et al 2022).
• Clinical practice guidelines on long chain omega-3 fatty acid supply in pregnancy for risk reduction of pre-term births have been published by leading international experts (Cetin et al 2024).

And FAB's Article Building a Baby's Brain - The First 1,000 Days

And for more on fish and seafood in pregnancy:

• Fish and Seafood in Pregnancy and Early Life - News
• Fish and Seafood in Pregnancy and Early Life - Research