London - Children born by caesarean section are more likely to suffer from food allergies than those born naturally, according to research.
The increase in allergies was present in both elective and emergency C-sections. The researchers said an extra five children in every 1 000 born by caesarean were being diagnosed with a food allergy compared to those born without surgery.
Food allergies, which can be fatal in extreme cases, are becoming more common – and the authors suggest that the increase in C-sections may be contributing to this. They estimate that the procedure could be the reason for an extra 17 percent of children with food allergies.
The reason is not known but researchers suggest the guts of babies born by C-sections are colonised by clostridium difficile bacteria, rather than those present in the mother’s birth canal.
This bug – which is resistant to many antibiotics – may disrupt the development of the gut. Ordinarily it would be "crowded out" by a mother’s own natural bacteria.
The study – by a team from Stockholm University and published in the Journal of Allergy and Clinical Immunology – was based on records of more than one million children born in Sweden between 2001 and 2012.
The authors based their findings of food allergies on medical diagnosis and suggest that their research may underestimate the number, as it does not take into account mild cases that may not have been identified by doctors.
Previous research found that clostridium difficile bacteria is commonly found in the intestines of babies born by caesarean.
Babies born "naturally" get their first gut bacteria from their mothers in the birth canal while C-section babies are first exposed to bacteria in the delivery room.