Want a Healthy Pregnancy? Two Supplements May Prevent Allergies and Skin Conditions in Babies

Taking fish oil supplements and probiotics may help expecting mothers protect their kids from developing food allergies and some skin disorders, according to a new study.

Researchers from Imperial College London reviewed the results of multiple studies to better understand how diet during pregnancy can influence the development of a child's immune system. The analysis encompassed a wide range of dietary practices, but one of the most striking results was to do with fish oil.

According to the study, recently published in the journal PLOS Medicine, fish oil might reduce food sensitivities. The researchers found that mothers who took fish oil supplements starting at about 20 weeks into pregnancy and continuing through the first few months of breastfeeding lowered the risk of their child having an egg allergy in early life—one of the most common types of allergies among children—by about 30 percent.

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The report also has some insights about probiotics. Pregnant women who take supplements containing Lactobacillus rhamnosus may help protect their future children from developing eczema, a common disorder that causes the skin to become itchy and inflamed, according to the data. The risk of eczema was reduced by 22 percent among children whose mothers took these probiotics.

However, the exact mechanism of the probiotics responsible for the reduced risk remains unclear, the authors note in their paper. And there's no clear evidence that taking the supplements directly caused the reduced reaction, whether for fish oil or probiotics.

"Food allergies and eczema in children are a growing problem across the world," Dr. Robert Boyle, lead author and pediatric allergy researcher at Imperial College London, said in a statement. "Although there has been a suggestion that what a woman eats during pregnancy may affect her baby's risk of developing allergies or eczema, until now there has never been such a comprehensive analysis of the data."

The researchers examined other dietary exposures, such as prebiotic supplements, vitamin intake, and fruit and vegetable consumption among mothers, but found that none of those influenced the risk of allergies or autoimmune disease.

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Fish oil supplements are often touted for their heart health benefits, but extensive evidence backing up those claims are lacking. And more research is needed clarify how fish oil and probiotics affect allergy and eczema risk, Vanessa Garcia-Larsen, study co-author and assistant nutrition professor at Johns Hopkins Bloomberg School of Public Health and honorary lecturer at Imperial College London, said in a statement.

"Taken together, our findings suggest that while infant diet may influence immune development through allergen-specific mechanisms, maternal diet during prenatal life and lactation may have broader effects on the developing immune system," Garcia-Larsen and her colleagues conclude in their published paper.

As they should with other supplements, pregnant mothers who are considering taking fish oil or probiotic supplements should consult their doctor first, the National Institutes of Health advises.