Early introduction of eggs, peanuts may reduce risk for developing allergies to them

Key takeaways:

• Introducing multiple allergenic foods in the first year of a child’s life was linked to lower risks for developing food allergy.
• Researchers observed a high rate of withdrawal from the intervention.

A systematic review and meta-analysis showed that earlier introduction of multiple allergenic foods from 2 to 12 months of age was associated with reduced IgE-mediated allergy to any food.

However, researchers identified a high rate of withdrawal, highlighting the need to develop interventions that are acceptable and safe.

Roberta Scarpone, MD, MPH, of Imperial College London’s School of Public Health, and colleagues wrote that earlier introduction of eggs and peanuts likely reduces the risk for allergies to those foods, but not much is known about where food allergy can be prevented as a whole using earlier introduction.

“Clinical practice guidelines now recommend earlier introduction of allergenic foods, and infant feeding practice has changed substantially in some regions,” Scarpone and colleagues wrote. “It is unknown whether earlier introduction of allergenic foods will reduce overall food allergy prevalence in populations. Prevention of one or two specific food allergies without preventing food allergy as a whole may have limited public health impact.”

Scarpone and colleagues conducted a systematic review and meta-analysis to better understand the associations between the timing of allergenic food introduction and risk for food allergy. Their findings were recently published in JAMA Pediatrics.

The researchers analyzed data from 23 randomized clinical trials that evaluated introductions to allergenic foods, such as milk, egg, nuts, peanuts and shellfish, during infancy and IgE-mediated food allergy from 1 to 5 years of age. Their analysis included 13,794 participants in the analysis.

Four trials that included just over 3,000 participants had moderate-certainty evidence that introducing multiple allergenic foods from 2 to 12 months of age was linked to reduced risk for food allergy (risk ratio [RR] = 0.49; 95% CI, 0.33-0.74). The absolute risk difference for a population with 5% incidence of food allergy was 26 cases (95% CI, 34 to 13 cases) per 1,000 population.

However, five trials with 4,703 participants had moderate-certainty evidence that introducing several allergenic foods from 2 to 12 months of age was linked to increased withdrawal from the intervention (RR = 2.29; 95% CI, 1.45-3.63). The absolute risk difference for a population with 20% withdrawal from the intervention was 258 cases (95% CI, 90-526 cases) per 1,000 population.

When it came to specific foods, Scarpone and colleagues wrote that the evidence for timing of introduction to cow’s milk and the risk for cow’s milk allergy was very low certainty.

However, nine trials with 4,811 participants had high-certainty evidence that introducing eggs from 3 to 6 months was linked to a reduced risk for egg allergy (RR = 0.6; 95% CI, 0.46-0.77) and four trials with 3,796 participants had high-certainty evidence that introducing peanuts from 3 to 10 months was linked to a reduced risk for the allergy (RR = 0.31; 95% CI, 0.19-0.51).

“The findings support the concept of using earlier allergenic food introduction to prevent food allergy but highlight the need for more acceptable forms of multiple allergenic foods,” Scarpone and colleagues wrote. “Notably, most complementary feeding interventions were initiated before 6 months of age, which is against World Health Organization infant feeding guidance.”