Micronutrients, omega-3 fatty acids and cognitive performance in Indian schoolchildren

In developing countries, approximately 30-40% of school-age children suffer from iodine and iron deficiencies. Poverty and consumption of monotonous diets are underlying causes of inadequate intakes of micronutrients and omega-3 fatty acids and may have severe consequences for children’s cognitive development. Multiple micronutrient interventions have shown to benefit mental performance of children, but a systematic evaluation of the evidence is currently lacking. The omega-3 fatty acid, -linolenic acid (ALA) is converted into docosahexaenoic acid (DHA), a major structural component of the brain, which is important for normal development and maintenance of brain function. At present, it is unclear whether additional intake of omega-3 fatty acids improves cognitive performance in children. The aim of this thesis was to investigate the role of multiple micronutrients and omega-3 fatty acids on cognitive performance in school-age children living in deprived environments, thereby addressing three main research questions. The first query concerned the investigation of the size of effects of multiple micronutrient interventions on different cognitive domains. Findings of our meta-analysis comprising 17 studies in children 5-16 years of age, suggested that multiple micronutrients were beneficial for fluid intelligence (i.e. reasoning abilities) (0.14 SD; 95% CI: -0.02, 0.29) and academic performance (0.30 SD; 95% CI: 0.01, 0.58). Crystallized intelligence (i.e. acquired knowledge) seemed not affected (-0.03 SD; 95% CI: -0.21, 0.15) and for the other cognitive domains data were too limited to draw firm conclusions. Secondly, we examined the role of omega-3 fatty acids on children’s cognitive development, for which a literature review was conducted. Associations between omega-3 fatty acid status or dietary intake and cognitive performance were investigated by cross-sectional analysis using baseline data of a randomized controlled trial in 598 Indian schoolchildren (see below for details). We found no evidence for a beneficial effect of additional intake of omega-3 fatty acids, and of DHA in particular, on cognitive development in school-age children. Neither there was a significant relationship between omega-3 fatty acid status and cognitive performance. Lastly, we studied the effect of different doses of micronutrients and omega-3 fatty acids, and their interaction, on cognitive performance. For that purpose, a randomized controlled trial in 598 Indian schoolchildren aged 6-10 years was conducted from November 2005 until March 2007. Children received either 15% or 100% of the Recommended Dietary Allowance of micronutrients in combination with either a low (140 mg ALA) or high dose (900 mg ALA plus 100 mg DHA) of omega-3 fatty acids for 12 months. Cognitive function was measured at baseline, 6 and 12 months. Our results showed that with some small differential effects on short term memory at 6 months (0.11 SD; 95% CI: 0.01-0.20) and fluid intelligence at 6 months (-0.10 SD; 95% CI: -0.17, -0.03) and 12 months (-0.12 SD; 95% CI: -0.20, -0.04), the high and low dose of micronutrients were as effective for improving retrieval ability, cognitive speediness and overall cognitive performance. Neither there were differences between the omega-3 fatty acid treatments, nor an interaction between micronutrients and omega-3 fatty acids on cognitive outcomes. In conclusion, although multiple micronutrients may benefit intellectual performance of schoolchildren, development of public health guidelines is currently premature. Further investigation on doses and composition of micronutrients would be needed to identify a cost-effective micronutrient supplement to optimize cognitive performance in children. Presently, no evidence exists for a positive effect of omega-3 fatty acids on cognitive performance in healthy children. A final trial using a higher dose and sufficiently long duration would be needed to conclude whether omega-3 fatty acid supplementation improves mental development at school age

Type 1 diabetes in youth::A psychosocial challenge

Snoek, F.J. [Promotor]Rotteveel, J. [Copromotor]Wit, M. de [Copromotor

Dietary patterns in infancy and cognitive and neuropsychological function in childhood

Trials in developing countries suggest that improving young children's diet may benefit cognitive development. Whether dietary composition influences young children's cognition in developed countries is unclear. Although many studies have examined the relation between type of milk received in infancy and subsequent cognition, there has been no investigation of the possible effect of variations in the weaning diet

Breast feeding and intergenerational social mobility: what are the mechanisms?

Objective To investigate the association between breast feeding and intergenerational social mobility and the possible mediating role of neurological and stress mechanisms. Design Secondary analysis of data from the 1958 and the 1970 British Cohort Studies. Setting Longitudinal study of individuals born in Britain during 1 week in 1958 and 1970. Participants 17 419 individuals participated in the 1958 cohort and 16 771 in the 1970 cohort. The effect of breast feeding on intergenerational social mobility from age 10/11 to age 33/34 was analysed after multiple imputations to fill in missing data and propensity score matching on a wide range of confounders measured in childhood (1958 cohort N=16 039-16 154; 1970 cohort N=16 255-16 361). Main outcome measures Own Registrar General's Social Class (RGSC) at 33/34 years adjusted for father's RGSC at 10/11 years, gender and their interaction. Results Breastfed individuals were more likely to be upwardly mobile (1958 cohort: OR 1.24 95% CI 1.12 to 1.38; 1970 cohort: OR 1.24 95% CI 1.12 to 1.37) and less likely to be downwardly mobile (1958 cohort: OR 0.81 95% CI 0.73 to 0.90; 1970 cohort: OR 0.79 95% CI 0.71 to 0.88). In an ordinal regression model, markers of neurological development (cognitive test scores) and stress (emotional stress scores) accounted for approximately 36% of the relationship between breast feeding and social mobility. Conclusions Breast feeding increased the odds of upward social mobility and decreased the odds of downward mobility. Consistent with a causal explanation, the findings were robust to matching on a large number of observable variables and effect sizes were alike for two cohorts with different social distributions of breast feeding. The effect was mediated in part through neurological and stress mechanisms

Open en gastvrij : een onderzoek naar het missionaire karakter van de zondagse samenkomsten in de Vrije Evangelisatie Zwolle

Masterthesis Missiologi

Zinc intake, status and indices of cognitive function in adults and children: a systematic review and meta-analysis

In developing countries, deficiencies of micronutrients are thought to have a major impact on child development; however, a consensus on the specific relationship between dietary zinc intake and cognitive function remains elusive. The aim of this systematic review was to examine the relationship between zinc intake, status and indices of cognitive function in children and adults. A systematic literature search was conducted using EMBASE, MEDLINE and Cochrane Library databases from inception to March 2014. Included studies were those that supplied zinc as supplements or measured dietary zinc intake. A meta-analysis of the extracted data was performed where sufficient data were available. Of all of the potentially relevant papers, 18 studies met the inclusion criteria, 12 of which were randomised controlled trials (RCTs; 11 in children and 1 in adults) and 6 were observational studies (2 in children and 4 in adults). Nine of the 18 studies reported a positive association between zinc intake or status with one or more measure of cognitive function. Meta-analysis of data from the adult’s studies was not possible because of limited number of studies. A meta-analysis of data from the six RCTs conducted in children revealed that there was no significant overall effect of zinc intake on any indices of cognitive function: intelligence, standard mean difference of <0.001 (95% confidence interval (CI) –0.12, 0.13) P=0.95; executive function, standard mean difference of 0.08 (95% CI, –0.06, 022) P=0.26; and motor skills standard mean difference of 0.11 (95% CI –0.17, 0.39) P=0.43. Heterogeneity in the study designs was a major limitation, hence only a small number (n=6) of studies could be included in the meta-analyses. Meta-analysis failed to show a significant effect of zinc supplementation on cognitive functioning in children though, taken as a whole, there were some small indicators of improvement on aspects of executive function and motor development following supplementation but high-quality RCTs are necessary to investigate this further

Changes in face-specific neural processes explain reduced cuteness and approachability of infants with cleft lip

The current study investigated whether changes in the neural processing of faces of infants with a facial abnormality – a cleft lip – mediate effects of the cleft lip on judgments of infant cuteness and approachability. Event-related potentials (ERPs) in response to pictures of faces of healthy infants and infants with a cleft lip, and ratings of cuteness and approachability of these infant faces, were obtained from 30 females. Infants with a cleft lip were rated as less attractive (less cute and approachable) than healthy infants, and both the N170 and P2 components of the ERP were of reduced amplitude in response to pictures of infants with a cleft lip. Importantly, decreased configural processing of infant faces with a cleft lip, as evidenced by reduced N170 amplitudes, mediated the reduced attractiveness ratings for infants with a cleft lip compared to healthy infants. Our findings help elucidate the mechanisms behind the less favorable responses to infants with a cleft lip, highlighting the role of face-specific rather than domain-general neural processes