The Change of Allergy Paradigm

From Avoidance to Early Exposure of Allergenic Food

The concept of early avoidance as prevention of future allergy has been challenged over recent years.

The presence of peanut allergy has increased over the past decade in countries that recommend peanuts avoidance during pregnancy, breastfeeding and during the infancy period of the baby. Peanut allergy affects approximately 1.5% of young children and tends to be diagnosed in those aged less than 2 years old.

Two groundbreaking research programs- LEAP and LEAP ON trials

LEAP (Learning Early About Peanut Allergy) is a randomized controlled clinical study performed by the Immune Tolerant Network (ITN) sponsored by the National Institute of Allergy and Infectious Diseases to find ways to prevent peanut allergy in young children. 

The study investigated over 600 children between age 4 to 11 months of age who are high risk for allergy to peanut. The risk severity is based on the history of egg allergy and/or severe eczema. The children are randomly separated into two groups- children who consume peanut-containing snack food 3 times a week, and children who avoid peanuts.

LEAP study revealed 17% of children who avoided peanut developed peanut allergy by the age of 5 years. Interestingly, only 3% of children who consumed peanut snack food developed a peanut allergy by 5 years of age. It showed the effectiveness of preventing peanut allergy by 80% later in life in high-risk infants who continuously consumed peanut beginning of their first 11 months of age in comparison to non-peanut consumers. 

LEAP ON study is a follow-up study from the original LEAP study to investigate whether the children who had consumed peanut for over 4 years had persistent protection against peanut allergy when they stopped eating peanut.  The study followed up 556 children from the original children in LEAP for a one-year period of peanut avoidance. After a year of avoiding peanuts, children from original peanut consumers showed only 4.8% of peanut allergy while 18.6% of the children with original peanut avoidance showed peanut allergy.

Encouraging Early Exposure of Allergenic Food in High-Risk Infants

The findings from LEAP and LEAP ON trials have challenged the old school of thoughts of avoiding allergenic food in early infancy in preventing the development of food allergy. Food guidelines over the world have been revamped, embracing and shifting food allergy concept to encouraging early repeated exposure of a child’s immune system to peanut at an early age, to allow the body to learn, adapt and tolerate peanut.

The Canadian Pediatric Society advises in their food guideline in early 2019 to offer babies with the risk of allergies, common allergenic food such as peanut butter and eggs, around the age of 6 months old, but not earlier than 4 months old.

In the United States, the food guidelines since 2017 have been recommending the introduction of peanuts in the early days of infancy to avoid peanut allergies.

In Singapore, common allergenic foods include eggs, peanuts and shellfish. It is advisable by most paediatricians for commencing common allergenic food between 4 to 6 months of age, and this should not be delayed beyond 6 months of age. Breastfeeding should be encouraged at least up to the first 6 months or even up to a year. Pregnant mothers are not advised to avoid allergenic food as the evidence remains inconclusive in reducing the risk of allergies in children.

Importantly, your children should receive a healthy balanced diet.

Speak to your doctor, or an allergist to find out more.