Exclusively breastfeeding infants linked to higher allergy rates in young children, study finds

While exclusive breastfeeding is widely recommended for its numerous health benefits, a new study from Japan indicates a potential link to increased allergy rates in young children, raising complex questions for parents.

The research, conducted by a team from the University of Toyama using data from the Japan Environment and Children’s Study (JECS), analyzed over 88,000 mother-child pairs. Infants were categorized based on their feeding methods: exclusively formula-fed, breastfed for less than six months, partially breastfed with formula, and exclusively breastfed (EBF) for six months. Children were monitored until age six for allergies.

The study confirmed some known advantages of EBF, including a lower risk of asthma in the first two years of life and a reduced risk of allergic rhinoconjunctivitis. However, it found a significant increase in the risk of developing food allergies. Exclusively breastfed children showed an 82% higher risk in their first year, decreasing to 62% at age two and 54% at age three, with the elevated risk gradually weakening over time. This effect was also noted to be more pronounced in male infants.

Researchers proposed that the age at which other foods are introduced into an infant's diet could be a contributing factor. Previous research suggests that early exposure to common allergens like eggs and peanuts between four and six months might help prevent allergies. The study's findings highlight the nuanced considerations involved in infant feeding choices, balancing the established benefits of breastfeeding against potential allergy risks.