Eating Salmon during Pregnancy Reduces Antibodies in Mother's Milk

Pregnant women are recommended to eat oily fish like salmon during pregnancy as it contains the nutrients required to support the baby's growth. But, according to a new study, it reduces the levels of disease-fighting antibodies in the mother's breast milk.

Until now, health experts used to advise pregnant women to include food rich with omega-3 that is essential for the growth of the brain, eyes, heart, and immune system and blood vessels of the baby.
"Pregnant women in the UK are currently advised to eat one or two servings of oily fish a week, while limiting tuna and avoiding shark, swordfish and king mackerel. This is intended to balance the need for sufficient levels of omega-3-rich food while limiting foods that might contain high levels of mercury," Parveen Yaqoob, Professor of Nutritional Physiology at the University of Reading, said in a statement.

Researchers from the University of Reading and the University of Southampton in the UK included 123 women to examine the other side of eating oily fish containing omega-3 fatty acids during pregnancy on the newborn.

The participants were asked to eat their normal diet or a food with high content of salmon. After giving birth, researchers tested content of the participants' milk. Researchers found breast milk of mothers who consumed high level of salmon during the last stages of pregnancy, containing high levels of omega-3 fatty acids after birth and very low levels of the antibody secretory immunoglobin-A (slgA) that protects the infant against infection.

However, investigators emphasize the need for more research to determine the risks posed by the low levels of antibodies on infants.

"While our study showed that pregnant women with diets high in oily fish passed on useful nutrients to their babies while breastfeeding, more research is needed to examine how the resulting lower levels of antibodies in breast milk could biologically affect young infants," Yaqoob said.

"From this study, it is positive to note that by following the current guidance on oily fish consumption during pregnancy, women can boost beneficial nutrients to help the early growth of their babies at a crucial stage of development. Breast milk contains a number of ingredients which contribute to immunity, and from this work we cannot say if the reduction in one type of antibody would have any effect on a baby's health."

The results of the study have been published in the Journal of Nutrition.