Developmental status of 1-year-old infants fed breast milk, cow's milk formula, or soy formula.
OBJECTIVE
Although soy formula has been reported to support normal development, concerns exist regarding potential adverse developmental effects of phytochemicals associated with soy protein. This study characterized developmental status (mental, motor, and language) of breastfed (BF), milk-based formula-fed (MF), or soy protein-based formula-fed (SF) infants during the first year of life.


METHODS
Healthy infants (N = 391) were assessed longitudinally at ages 3, 6, 9, and 12 months. Development was evaluated by using the Bayley Scales of Infant Development and the Preschool Language Scale-3. Mixed effects models were used while adjusting for socioeconomic status, mother's age and IQ, gestational age, gender, birth weight, head circumference, race, age, and diet history.


RESULTS
No differences were found between formula-fed infants (MF versus SF). BF infants scored slightly higher than formula-fed infants on the Mental Developmental Index (MDI) score at ages 6 and 12 months (P < .05). Infants who were breastfed also had higher Psychomotor Development Index scores than SF infants at age 6 months and slightly higher Preschool Language Scale-3 scores than MF infants at ages 3 and 6 months (P < .05). In addition, BF infants had a lower probability to score within the lower MDI quartile compared with MF infants and a higher likelihood to score within the upper quartile for the MDI and Psychomotor Development Index compared with SF infants.


CONCLUSIONS
This unique study showed that all scores on developmental testing were within established normal ranges and that MF and SF groups did not differ significantly. Furthermore, this study demonstrated a slight advantage of BF infants on cognitive development compared with formula-fed infants.
Arkansas Children’s Nutrition Center, Little Rock, Arkansas 72202, USA. andresaline@uams.edu
Aline
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Andres
Mario A
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Jayne B
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Bellando
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Pivik
Patrick H
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Casey
Thomas M
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Badger
D000818:Animals; D001903:Bottle Feeding / Q000523:psychology; D001942:Breast Feeding / Q000523:psychology; D002417:Cattle; D002657:Child Development / Q000187:drug effects / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D018730:Infant Behavior / Q000187:drug effects / Q000502:physiology* / Q000523:psychology; D041943:Infant Formula / Q000008:administration & dosage*; D008297:Male; D008892:Milk; D008895:Milk, Human / Q000502:physiology; D030262:Soybean Proteins / Q000008:administration & dosage*
D030262:Soybean Proteins