Study Questions Pregnancy Fish Limit
Research Shows FDA Advice Does More Harm Than Good to Babies
Feb. 15, 2007 -- Pregnant women who limit their fish consumption to
recommended government levels may be doing their unborn babies more harm than
good, according to a study from the National Institutes of Health.
Researchers found that women who ate less than 12 ounces of fish or other
seafood a week while pregnant were more likely to have children with verbal and
other developmental delays than women who ate more than 12 ounces each
The findings challenge guidelines from the FDA that advise pregnant women to
limit their weekly seafood consumption to 12 ounces, or about two average
The FDA advisory stemmed from concerns that eating more fish could impair
brain development by exposing developing fetuses to dangerously high levels of
But seafood is also a major dietary source of omega-3 fatty acids, which are
critical for brain development.
The new findings suggest that, for developing brains, the risks of limiting
seafood consumption outweigh the benefits of such a limit, the NIH’s Joseph R.
Hibbeln, MD, tells WebMD.
“Regrettably, these data indicate that the [FDA-EPA] advisory apparently
causes the harm that it was intended to prevent, especially with regard to
verbal development,” Hibbeln says.
Limiting Fish May Not Be Beneficial
Hibbeln analyzed data collected on close to 12,000 pregnant women in Britain
who participated in one of the largest and most comprehensive pregnancy outcome
studies ever conducted.
When they were 32 weeks pregnant, the women were asked to fill out detailed
questionnaires on the foods they ate during pregnancy.
The British researchers tracked the developmental progress of the children
born to the women through age 8, using standardized IQ and other tests.
Twelve percent of the women in the study reported eating no seafood during
pregnancy, while 65% reported eating up to 12 ounces of seafood a week, and 23%
reported eating more than 12 ounces weekly.
After adjusting for 28 separate potential risk factors for delayed
development, Hibbeln and colleagues concluded that children born to women who
ate 12 ounces or less were at increased risk for low verbal IQ and other
developmental problems, compared with those who ate more than 12 ounces a
They also concluded that eating more than 12 ounces of fish a week during
pregnancy “benefited a child’s neurodevelopment” -- or brain development.
“We did not find compliance with the advisory [to limit seafood consumption]
to be of any benefit,” Hibbeln says.
“In contrast, we found that compliance with the advisory was associated with
harm, specifically with regard to verbal development,” he says.
What Should Pregnant Women Do?
Hibbeln stopped short of saying that pregnant women should ignore the
FDA-EPA guidelines, or that the federal agencies should change their
“It is not the role of the NIH to advise anyone to revisit their
recommendations,” he says.