A recent investigation spearheaded by researchers at the RIKEN Center for Integrative Medical Sciences has uncovered a significant connection between specific gut bacteria present in one-month-old infants and their likelihood of developing food sensitivities, particularly to eggs. This study also identified factors influencing the types of bacteria found in newborns' guts. The findings suggest that targeted probiotic supplements could serve as an early intervention to mitigate food allergies, especially among high-risk infants. The research was published in the Journal of Allergy and Clinical Immunology.
The human gut is home to diverse microorganisms that play a crucial role in immune system development and disease prevention. Despite this, previous studies on the relationship between gut microbiota and food allergies have yielded inconsistent results. To address this gap, the team conducted a comprehensive analysis spanning seven years, involving two distinct groups of Japanese children. One group comprised 270 infants from families with a history of allergies, while the other included 245 children from a prior study focused on allergy treatments.
Food allergies occur when the body misidentifies certain food proteins as harmful, triggering an immune response through the production of immunoglobulin E (IgE) antibodies. Researchers measured milk-, peanut-, egg white-, and wheat-specific IgE levels in the blood from infancy until age seven. Concurrently, they collected gut microbiota data starting from the first week after birth. By correlating these datasets, the researchers aimed to identify predictive biomarkers for food sensitization and allergies.
The most striking discovery was that the composition of gut microbiota one month after birth had the strongest association with food-specific IgE levels, even up to seven years later. According to Hiroshi Ohno, "The early neonatal period is critical for immune system development, and our findings underscore this, showing that the type of gut bacteria present during this time best predicts immune responses to food years later."
The study classified gut bacteria into three dominant types observed in infants one month old. Babies with a predominance of Bifidobacterium (type-3 microbiomes) were significantly less likely to develop sensitivities to egg whites compared to those with other types of gut bacteria. This trend persisted for allergic reactions to egg whites later in life. Factors such as mode of delivery and breastfeeding practices influenced the type of gut bacteria present. Normal deliveries with moderate breastfeeding led to type-3 microbiomes, whereas high breastfeeding rates or Cesarean sections resulted in different bacterial compositions.
This research underscores the potential of neonatal gut microbiota as a key factor in food allergy prevention. Interventions aimed at promoting Bifidobacterium during infancy might offer a promising strategy to reduce the incidence of food allergies, particularly in at-risk populations. The insights gained from this study pave the way for innovative preventive measures and further exploration into the intricate relationship between gut health and immune responses.