The systematic review of the evidence, published by The Cochrane Library, drew together data from four clinical studies involving a total of 1,428 children; finding that eczema was significantly reduced in children who were fed formula containing prebiotics.
However the review team, led by John Sinn from the University of Sydney in Sydney, Australia, revealed that the evidence for allergies was weaker - noting that the number of children who developed asthma was similar whether they were given formula with added prebiotics or without, while the one study looking at urticaria (hives) found that giving children formula containing prebiotics did not prevent any cases of the allergy.
“Given these findings, it remains unclear whether the use of prebiotics should be restricted to infants at high risk of allergy or may have an effect in low risk populations,” said Sinn.
“Overall, we found some evidence that infant formula containing prebiotic supplements can help prevent eczema in children up to two years of age,” he said. “However, the quality of existing evidence is generally low or very low."
"More high quality research is needed before we can recommend routine use of prebiotics for prevention of allergy."
Much research has suggested that the microbiota – the bacterial ecosystem lining the gut - may play an important role in a child developing sensitivities to certain foods and allergens by regulating immune responses and determining how they will react to the same substances in later life.
Prebiotics are indigestible components of foods such as breast milk, fruit and vegetables that are known to stimulate the growth and activity of the beneficial strains of bacteria in the gut. They are distinct from probiotics – which are cultures of live bacteria like those added to yoghurts and infant formula.
Prebiotics can also be added to infant formula. However, the review team noted that, as yet, it is unclear exactly what effect these supplements have on the development of allergies.