- A pregnant woman's diet can affect her baby's allergy and eczema risk
- The risk of egg allergy in the child was reduced when pregnant women took a daily fish oil capsule in the 20th week, and during the first 3 to 4 months of breastfeeding.
- A daily dose of the probiotic supplement from 36-38 weeks of pregnancy, and during the first 3 to 6 months of breastfeeding can reduce the risk of a child developing eczema.
Fish oil and probiotic supplements taken by pregnant mothers can help reduce a child's risk of getting allergies or eczema, reveals a new study.
Scientists from Imperial College London assessed over 400 studies, where about 1.5 million people were involved in the studies. The research team published their meta-analysis in the journal PLOS Medicine.
No evidence was found that avoiding allergenic foods like nuts, dairy, and eggs during pregnancy reduces a child's eczema risk or allergy.
‘The Food Standards Agency advises that families need to continue to follow the current Government advice to exclusively breastfeed for around the first six months of age, and continue breastfeeding after that.’
Food Allergies and Eczema in Children
Dr. Robert Boyle, the lead author of the research from the Department of Medicine at Imperial College London, explained: "Food allergies and eczema in children are a growing problem across the world. 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."
Dr. Boyle also added that this research reveals that probiotic and fish oil supplements can reduce the child's risk of developing an allergic condition. Also, these findings need to be included in the guidelines for pregnant women.
The team also assessed some dietary factors during pregnancy such as vitamin intake, consumption of fruits and vegetables and they found no clear evidence that these can affect allergy or eczema risk.
About 1 in 20 children in the UK are affected by food allergies like nuts, egg, milk or wheat.
Allergies are caused by the immune system malfunctioning and children over-reacting to these simple, harmless foods, which can trigger symptoms like rashes, swelling, vomiting, and wheezing.
One in five children is affected with eczema in the UK,
which causes dry, cracked and itchy skin. However, the causes of eczema and allergies are not fully known. Allergies are common in people who suffer from eczema.
Further research is needed to understand how probiotics and fish oils reduce allergy and eczema risk, said Dr Vanessa Garcia-Larsen, co-author of the study from the National Heart and Lung Institute at Imperial: "Despite allergies and eczema being on the rise and affecting millions of children, we are still hunting for the causes of these conditions, and how to prevent them."
Dr. Garcia-Larsen, who is also based at John Hopkins University, said that this study provides clues, which can help other scientists in the future.
Probiotic Supplements during Pregnancy
In this study, the research team assessed 28 trials of probiotic supplements during pregnancy, which involved about 6,000 women.
Probiotics are live bacteria that influence the natural balance of bugs in the gut.
In previous studies, a disruption in naturally-occurring bacteria was linked to allergy risk.
In this research, women took probiotics during pregnancy and breastfeeding as a capsule, powder or drink (most yogurts do not contain enough probiotic), which reduced the risk of developing eczema in children who are in the age group of six months to three years by 22 percent and is the equivalent of 44 cases of eczema per 1000 children.
However, the probiotics that contained a bacterium called Lactobacillus rhamnosus was not used in early pregnancy.
Fish Oil Supplements during Pregnancy
The research team also assessed about 19 trials of fish oil supplements during pregnancy, where 15,000 people were involved in the study. The results revealed a 30 percent reduction in egg allergy risk by age one, which equates to a decrease of 31 cases of egg allergy per 1000 children.
Egg allergy was tested with a skin test, where a tiny amount of egg is pricked onto the skin.
In the studies that used fish oil supplements, the capsules had a standard dose of omega-3 fatty acids. However, omega-6 did not affect allergy risk.
Dr. Boyle said that previous research studies suggest that fish oils can destroy the immune system, and prevent it from over-reacting.
Most of the trials used supplements, eating oily fish was included in one trial, and in others, non-fish oils like nut oils were used.
The Department of Health advises women to consume no more than two portions of oily fish per week, and to avoid shark, marlin or swordfish, as they contain high levels of mercury.
In this study, taking fish oil supplements during pregnancy was found to reduce the child's risk of peanut allergy by 38 percent. However, this was based only on two studies, and cannot be as reliable as the egg allergy and eczema results.
Specific evidence was found between longer duration of breastfeeding and a reduced risk of eczema, and breastfeeding, which were linked to lowering the risk of type one diabetes.
Pregnant Women need to Follow Current Guidelines
The study was funded by the Food Standards Agency, and the findings are being considered by the Government alongside the wider evidence base on infant feeding and the introduction of solids.
The risks and benefits associated with the timing of introduction of allergenic foods need to be considered, as part of the cross-government review of complementary feeding.
The Food Standards Agency advises that families need to continue to follow the current Government advice to exclusively breastfeed for around the first six months of age, and continue breastfeeding after that.
Solid foods should be introduced to the infant at around six months of age. Women who are pregnant should also continue to follow government dietary and supplement advice.