How allergenic are hypoallergenic infant formulae?

Area of Science:

• Allergy and Immunology
• Pediatric Nutrition
• Food Science

Background:

• Infant formulas marketed as hypoallergenic are intended for infants with cow's milk allergy.
• The effectiveness of hypoallergenic formulas relies on reduced allergenicity.
• Variability in protein hydrolysate processing may affect residual allergenicity.

Purpose of the Study:

• To compare the allergenicity of six different 'hypoallergenic' infant formulas.
• To identify which types of protein hydrolysates are least allergenic for cow's milk allergic infants.

Main Methods:

• Comparative study of six protein hydrolysates.
• Skin prick tests
• RAST (Radioallergosorbent test) and RAST inhibition assays
• Titrated provocation tests

Main Results:

• Hydrolysates with a higher percentage of larger peptides demonstrated the greatest capacity to induce positive skin tests and provocation tests.
• These larger peptide hydrolysates also showed higher binding to IgE antibodies in cow's milk allergic children.
• Casein hydrolysates exhibited the least residual allergenic activity among the tested formulas.

Conclusions:

• Not all 'hypoallergenic' infant formulas are equally effective in reducing allergenicity.
• The size of peptides in protein hydrolysates is a critical factor in residual allergenicity.
• Individual testing of hypoallergenic formulas is crucial before prescription for cow's milk sensitive infants.