Authors: Carole McCorry MS, RD, CSP—Maternal Health Dietitian at South Shore Hospital, specializing in nutrition for pregnancy, preterm infants and pediatric patients & Wendy Barrett MS RD, CDE—Maternal Health Specialist at South Shore Hospital’s Diabetes Center.
Pregnancy has a way of bringing out a mother’s sense of urgency to become an expert in all areas concerning the health and well-being of her and the precious cargo she carries. Nutrition is one such area that can have women feeling overwhelmed—usually because of the overabundance of information available (some accurate, some not)—that often make dietary decisions during pregnancy rather challenging.
The fact is: a woman’s choice of food intake during pregnancy and lactation can have significant effects on her child’s lifetime health and development. Over time it is proven that a well-balanced diet will yield optimum outcomes for mothers and infants. The question of including fish in this well-balanced equation has been debated for years, with many women even avoiding fish altogether due to the negative media attention about potential contaminants.
Fish can be a great source of protein, iron and zinc—all vital nutrients for your baby's growth and development. Additionally, fish contain unique nutrients such as choline and omega-3 fatty acids (DHA), which collectively play a role on brain and eye development—even promoting IQ scores later in life.
The current recommendations by the US FDA state that all pregnant women and women of reproductive age should consume 8-12 ounces of a variety of fish per week, or 2-3 servings per week. Wild or farmed, low mercury fish should be a regular part of the diet. Choose fish such as salmon, shrimp, pollock, light canned tuna, tilapia, or cod.
Some types of seafood—particularly larger fish such as shark, swordfish, king mackerel and tilefish from the Gulf of Mexico contain higher levels of mercury, which during pregnancy should be eaten with precaution. Too much mercury in your bloodstream could ultimately damage your baby's developing brain and nervous system. Also limit consumption of white albacore tuna to 6 ounces per week.
For children, 3-6 ounces of fish per week, is sufficient to have beneficial effects on brain development.
Research from around the world was evaluated by the World Health Organization (WHO). The overall finding is that consuming fish while pregnant contributes to optimal brain and nervous system development in the offspring and the risks of not eating fish outweigh the risks of eating fish. The WHO recommends consumption of up to three ounces per day of low mercury fish.
From WHO Paper:
1) The Expert Consultation finds the evidence convincing that maternal fish consumption contributes to optimal neurodevelopment in their offspring.
2) With a central estimate of methylmercury risk, neurodevelopmental risks of not eating fish exceed risks of eating fish for up to at least seven 100 g servings per week and methylmercury levels up to at least 1 μg/g.
3) With an upper estimate of methylmercury risk, neurodevelopmental risks of not eating fish exceed risks of eating fish for up to at least seven 100 g servings per week for all fish containing less than 0.5 μg/g methylmercury.