FDA Updates Fish Consumption Recommendations

Written by on August 1, 2014 in Research & Technology - No comments

A brief review of the research

The FDA/EPA recently announced it is updating the recommendation for fish consumption by pregnant, breastfeeding women and young children.  The previous recommendation issued in 2004 encouraged pregnant women and young children to eat up to 12 ounces of low mercury fish per week. The new recommendation is placing an emphasis on a minimum of 8 ounces of fish per week with the maximum amount of fish still at 12 ounces per week, which correlates to 2-3 servings per week.

FishDinnerWEBSo what prompted the change to the previous recommendation? The FDA did an extensive review of the literature in 2009 looking at the risks from methylmercury, the type of mercury found in fish, compared to the benefits of nutrients from fish in the diet. They started looking at several studies from Japan and Iraq that evaluated patients poisoned by high levels of methylmercury from contaminated sources. The studies showed these patients suffered from various neurological symptoms including paresthesia, ataxia, visual effects, and difficulties with speech and hearing. The symptoms ranged from mild to severe depending on the patient’s level of methylmercury exposure. Unborn babies and young children were found to be more sensitive to the effects of methylmercury poisoning than adults. The effects included congenital cerebral palsy, mental retardation, primitive reflex, deformities of the limbs, and disturbances in physical development and nutrition. These studies showed a clear risk from extremely high exposure to methylmercury, but this isn’t necessarily the exposure the average person receives while eating fish in a regular diet.

To determine the lowest amount of methylmercury exposure that could be consumed in the diet and still be deemed safe, the FDA examined island populations that had a high level of fish consumption in their regular diet. The analysis of these studies began to show that consuming certain types of fish high in methylmercury had a negative impact on the performance of children on various neurodevelopment tests. While consuming diets high in fish that contained low amounts of methylmercury had a positive effect on the neurodevelopmental testing of children, although this benefit seemed to plateau with higher levels of fish intake. These effects appeared to be especially prominent in the fetus and young child. Unfortunately, these studies did not indicate the ideal amount of fish that should be consumed to maximize the neurodevelopmental benefit, but they did allow researchers to extrapolate the beneficial effects of fish to omega-3 DHA.

Studies, which specifically looked at fish consumption during pregnancy, were then reviewed. Four particular studies were done in the United States that looked at the benefits of following the previous FDA recommendation of eating up to three servings of fish per week during pregnancy. These studies found that the most benefit from fish, especially fish low in mercury, occurred when a minimum of two servings per week was consumed on a regular basis.  Children whose mothers ate fish in pregnancy were more likely to meet developmental milestones, less likely to have IQ’s in the bottom 25th percentile, and performed better on development tests. They did find that a higher consumption of fish, and thus mercury, lowered these beneficial effects but this did not occur in people who ate less than the recommended three servings of low mercury fish per week.

Only four studies have been done in children looking at the benefits from the nutrients in fish versus the effects of methylmercury. Overall, they show a benefit in neurological development scores and IQ testing in children that eat fish compared to children that don’t eat fish but no specific amount of fish consumption was studied. No studies have been done that look at the effects on the infant from breastfeeding mothers who consume fish in their diet.

From the evidence in this extensive review, the FDA/EPA released its newest recommendations for consumption of fish by young children and women who are pregnant or lactating. They recommend these populations should do the following:

-Consume a minimum of 8 ounces and up to a maximum of 12 ounces of low mercury fish per week, which includes shrimp, Pollock, salmon, canned light tuna, tilapia, catfish, and cod
-Avoid fish with the highest levels of mercury including tilefish from the Gulf of Mexico, shark, swordfish, and king mackerel
-Limit the consumption of white (albacore) tuna to no more than 6 ounces per week
-If eating fish caught from local rivers and lakes follow local fish advisories or consume no more than 6 ounces per week and 1-3 ounces for children

Despite the new recommendation to encourage more fish consumption in pregnancy, the FDA found that current fish consumption in pregnancy is rather dismal. A poll of 1000 pregnant women showed 20% of pregnant women ate no fish in the last month, 50% ate less than 2 ounces per week, and 75% ate less than 4 ounces per week. The FDA is hoping this new recommendation will bring more public awareness to the health benefits of eating fish in pregnancy, during lactation, and in early childhood. As the research clearly indicates the developing neurological system of infants and young children benefit greatly from the nutrients in low mercury fish.

References: www.Fda.gov

By Carrie A. Noriega, MD

Leave a Comment

Please type the characters of this captcha image in the input box

Please type the characters of this captcha image in the input box