Soya-Based Infant Formula in Milk Allergy

In a randomised multicentre study 1 only one of the 93 children with IgE-mediated milk allergy became sensitised to the soya-based infant formula (Isomil, Abbott). The age of the children varied from 3 months to 3.5 years (3.2 % less than 6 months, 17.2 % 6 months - 1 year), and they received a soya formula (579 +/- 31 ml/day) for one year.

A prospective study 2 was carried out in 43 children (aged 3 - 27 months, mean age 8.37 months) with suspected milk-induced and/or soya protein-induced enterocolitis (symptoms included vomiting and/or chronic diarrhoea with mucous/blood). After a 4 - 12 week period of using a special “pre-digested” feeding formula the children were challenged for cow's milk and two different soya-based infant formulas. Infants with IgE-mediated food allergy were excluded from the study. The difference between the tolerability of two soya products was evaluated. A significant number of children with milk protein enterocolitis are also intolerant of soya. The tolerability of the liquid and powder soya formulas was dependent on their sequence of administration. It was suggested that this may be attributable to a local intestinal immune effect.

Of infants with proctocolitis or enterocolitis, 25 - 60 % will become symptomatic both to cow's milk and soya 3.

The energy and nutrient content of soya-based infant formulas fulfil the requirements of children's dietary recommendations. The growth patterns of healthy infants fed with soya formulas are similar to those of controls fed with cow's milk-based formulas 4.

Ninety-three children with cow's milk allergy (3.2 % less than 6 months, 17.2 % 6 months - 1 year) were fed with a soya-based infant formula (Isomil, Abbott) for one year 1. The children consumed 579 +/- 31 ml/day of the soya-based formula. Improved growth (p < 0.05) occurred during the use of the soya-based formula.

A retrospective cohort study 5, carried out as a telephone interview, was conducted in subjects aged between 20 and 34 years, who, as infants aged between 9 days and 16 weeks, had been fed with a soya-based formula (248 young adults). The control group consisted of 563 subjects who had been fed a cow's milk formula at the same time during their infancy. Soya contains phytoestrogens, in the form of soya isoflavonoids. The long-term effects of soya isoflavonoids received in infancy were examined in relation to endocrinological factors and reproductive health. According to the study, exposure to soya-based formulas in early infancy does not lead to different later health risks than exposure to cow's milk formulas.

References

• Zeiger RS, Sampson HA, Bock SA, Burks AW Jr, Harden K, Noone S, Martin D, Leung S, Wilson G. Soy allergy in infants and children with IgE-associated cow's milk allergy. J Pediatr 1999 May;134(5):614-22. [PubMed]
• Burks AW, Casteel HB, Fiedorek SC, Williams LW, Pumphrey CL. Prospective oral food challenge study of two soybean protein isolates in patients with possible milk or soy protein enterocolitis. Pediatr Allergy Immunol 1994 Feb;5(1):40-5. [PubMed]
• Powell GK. Milk- and soy-induced enterocolitis of infancy. Clinical features and standardization of challenge. J Pediatr 1978 Oct;93(4):553-60. [PubMed]
• Köhler L, Meeuwisse G, Mortensson W. Food intake and growth of infants between six and twenty-six weeks of age on breast milk, cow's milk formula, or soy formula. Acta Paediatr Scand 1984 Jan;73(1):40-8. [PubMed]
• Strom BL, Schinnar R, Ziegler EE, Barnhart KT, Sammel MD, Macones GA, Stallings VA, Drulis JM, Nelson SE, Hanson SA. Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood. JAMA 2001 Aug 15;286(7):807-14. [PubMed]