Relationship between early diet and subsequent cognitive performance during adolescence.

The possibility that a nutritional stimulus or insult at a critical period of development could have a long-term influence on health, function or achievement is one of uncertainty but one of major importance. A number of investigators have examined the relationship between breastfeeding and childhood cognitive development [ 1-81 and have indicated that breastfed infants may be advantaged in their subsequent development and intelligence quotient (IQ) compared to non-breastfed infants. These studies have focussed their attention on the relationship between early nutrition and cognitive development during early childhood, but whether the observed advantageous association persists during later childhood and beyond is uncertain. and will be examined in this paper. 432 subjects. 208 males, 224 females aged 11-16 years from seven comprehensive schools within the South Tees area were recruited. The 0-4 years hospital consultation records. health visitor reports and school health records of each sub.ject were obtained and from these data on birthweight, gestational age, mother’s age. birth rank and method of infant feeding were collected. Information was also collected on social class which was coded using the Registrar General’s classification [91 based on the occupation of the income providing parent or on the father’s occupation if both parents were earning. Mother’s education was coded as follows: I = no educational attainments, 2 = up to four passes for the certificate of secondary education (CSE), 3 = any general certificate of education (GCE) at ordinary (0) level or more than four CSEs, 4 = any GCE at advanced (A) level, and 5 = degree or higher professional qualification. Cognitive ability was assessed using the Raven’s Standard Progrekve Matrices test [ 101 and subtesk of the Primary Mental Abilities test [ I I ] namely. verbal meaning, reasoning and number facility. All tests used are standardised measures of assessing cognitive abilities within this age group. Statistical analyses used were Student’s t test, chi-square and multiple regression analysis. Regression analysis was used to adjust for possible confounding factors, shown to be related to developmental scores [ 121 and which might confound the comparison of IQ scores between the breastfed and non-breastfed groups. These factors included birthweight, gestational age, birth rank, child’s sex, social class, mother’s age and mother’s educational level. No significant difference in birthweight, gestational age, mother’s age or child’s sex were observed between the breastfed and nonbreast fed groups. However, there was a significantly greater tendency for the first child in a family to be breastfed ( ~ 4 . 0 1 ) . A significant difference between the two groups was also observed for social class and mother’s education level, with 29% of families from social class I and I I (p<0.001) and 83% of mothers with GCE “0 ’ levels or above (p<0.01) choosing to breastfeed.