Abstract
Diet supplies the nutrients needed for the development of neural tissues that occurs over the first 2 years of life. Our aim was to examine associations between dietary patterns at 6, 15 and 24 months and intelligence quotient (IQ) scores at 8 years. Participants were enrolled in an observational birth cohort (ALSPAC study, n = 7,097). Dietary data was collected by questionnaire and patterns were extracted at each time using principal component analysis. IQ was measured using the Wechsler Intelligence Scale for Children at 8 years. Associations between dietary patterns and IQ were examined in regression analyses adjusted for potential confounding and by propensity score matching, with data imputation for missing values. At all ages, higher scores on a Discretionary pattern (characterized by biscuits, chocolate, sweets, soda, crisps) were associated with 1–2 point lower IQ. A Breastfeeding pattern at 6 months and Home-made contemporary patterns at 15 and 24 months (herbs, legumes, cheese, raw fruit and vegetables) were associated with 1-to-2 point higher IQ. A Home-made traditional pattern (meat, cooked vegetables, desserts) at 6 months was positively associated with higher IQ scores, but there was no association with similar patterns at 15 or 24 months. Negative associations were found with patterns characterized by Ready-prepared baby foods at 6 and 15 months and positive associations with a Ready-to-eat foods pattern at 24 months. Propensity score analyses were consistent with regression analyses. This study suggests that dietary patterns from 6 to 24 months may have a small but persistent effect on IQ at 8 years.
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Abbreviations
- ALSPAC:
-
Avon longitudinal study of parents and children
- CSE:
-
Certificate of secondary education
- FSIQ:
-
Full scale intelligence quotient
- HM:
-
Home-made
- IQ:
-
Intelligence quotient
- PCA:
-
Principal component analysis
- PIQ:
-
Performance intelligence quotient
- RM:
-
Ready-prepared
- VIQ:
-
Verbal intelligence quotient
- WISC:
-
Wechsler intelligence scale for children
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Acknowledgments
We are extremely grateful to all the families who took part in this study, the midwives for their help in recruiting them, and the whole ALSPAC team, which includes interviewers, computer and laboratory technicians, clerical workers, research scientists, volunteers, managers, receptionists and nurses. The UK Medical Research Council, the Wellcome Trust (Grant ref: 092731) and the University of Bristol provide core support for the ALSPAC study. JWL is supported by an Australia Fellowship (570120) and RKG with a Postdoctoral Training Fellowship (478115) from the National Health and Medical Research Council of Australia. LGS, LB and MNM are supported by funds from the Australia Fellowship awarded to JWL. KN and PE are partly supported by funding from European Community’s Seventh Framework Programme (245012).
Conflict of interest
PE and KN have both received support from commercial infant food manufacturers and undertaken invited lectures. The other authors have no conflicts of interest to declare.
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Smithers, L.G., Golley, R.K., Mittinty, M.N. et al. Dietary patterns at 6, 15 and 24 months of age are associated with IQ at 8 years of age. Eur J Epidemiol 27, 525–535 (2012). https://doi.org/10.1007/s10654-012-9715-5
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DOI: https://doi.org/10.1007/s10654-012-9715-5