Modified proteins in allergy prevention.

Around 2.5% of neonates experience hypersensitivity reactions to cow's milk protein during the first year of life, which is highly associated with early exposure to cow's milk. To prevent early allergy development, cow's milk proteins in infant formulas were modified by hydrolyzation processes for use in children at high atopic risk who need milk supplementation in the first months of life. Dependent on the degree of modification, hydrolyzed cow's milk formulas are differentiated into extensively and partially hydrolyzed whey or casein hydrolysates (pHF, eHF). However, their allergy-preventive potential seems not only to dependent on the degree but also on the process of hydrolysis. pHF and eHF can be used for primary prevention of allergy in infants at high atopic risk, while only eHFs are indicated for secondary prevention in patients with manifest cow's milk allergy. In clinical trials a consistent trend to a reduction in atopy, mainly atopic eczema and food allergy, by certain pHFs and eHFs could be demonstrated in children with a familial risk of atopy until the age of 6 years. Because more than 50% of allergic children do not have a family history of atopy, it would be worthwhile to consider primary allergy prevention with hydrolysates for all children who need supplementation to breastfeeding.