Association of dietary diversity and cognition in preschoolers in rural China

Dietary diversity and development among early childhood children in rural China

Background

Early childhood is a critical period for cognitive development, heavily influenced by nutrition. Despite significant economic advancements, malnutrition and micronutrient deficiencies persist in many low- and middle-income countries, including China, where dietary diversity remains suboptimal. Existing research predominantly relies on correlational data, underscoring the need for more rigorous empirical evidence. This study aims to fill that gap by providing stronger empirical evidence on the relationship between dietary diversity and developmental outcomes in rural Chinese children.

Methods

We conducted a longitudinal cohort study of 1,207 children aged 6-23 months, drawn from 100 villages across 22 counties in rural China, with three follow-up rounds extending until the children reached 51-83 months of age. Cognitive and non-cognitive development, as well as key health indicators, were evaluated. Cognitive development was measured using the Bayley Scales of Infant and Toddler Development and the Wechsler Preschool and Primary Scale of Intelligence Fourth Edition. Non-cognitive development was assessed via the Ages and Stages Questionnaire: Social-Emotional and the Strengths and Difficulties Questionnaire. Health indicators included anemia, frequency of illness in the past 2 weeks, and four key anthropometric measures (height-for-age z-scores, weight-for-age z-scores, weight-for-height z-scores, and body mass index-for-age z-scores). Multiple linear regression models were applied to analyze the relationship between dietary diversity scores (DDS) and developmental outcomes, incorporating child fixed effects and adjustments for time-variant confounders. We accounted for the hierarchical structure of the data by clustering standard errors at the village level, which also reflects the township level.

Results

The regression analysis identified significant positive associations between DDS and cognitive (p < 0.01), as well as reduced illness incidence (p < 0.001) in children aged 6-54 months. Additionally, DDS demonstrated a strong positive effect on non-cognitive development (p < 0.001) in children 2 years and older. The associations between DDS, non-cognitive development (p < 0.01), and illnesses reduction (p < 0.001) remained robust under two-way fixed effects models.

Implications

To promote sustainable improvements in child development and health, policymakers should prioritize nutrition-focused interventions in rural areas. Community-based programs offering caregivers training and nutritional support, integrated within healthcare and social services infrastructures, are vital for ensuring families have the necessary resources enhance child wellbeing and long-term developmental outcomes.

8-Year Follow-up of a Maternal Education Trial in a Low-Resource Setting

OBJECTIVES

Nutrition and stimulation interventions promote early childhood development, but little is known about their long-term benefits in low- and middle-income countries. We conducted a follow-up study of a cluster-randomized maternal education trial performed in children aged 6 to 8 months to assess the sustainability of developmental benefits after 8 years.

METHODS

The education intervention lasted 6 months and consisted of nutrition, hygiene, sanitation, and child stimulation aspects. We assessed child processing and cognitive abilities using the Kaufman Assessment Battery for Children Second Edition (KABC-II) and attention and inhibitory control using the Test of Variables of Attention after 8 years. The original trial included 511 mother-child pairs (intervention, n = 263; control, n = 248), whereas in the current study, 361 (71%; intervention, n = 185; control, n = 176) pairs were available for analyses.

RESULTS

The intervention group scored higher than the controls (all P < .001) on all 5 KABC-II subscales and on the KABC-II global score (mean difference: 14; 95% confidence interval, 12-16; P < .001). For all 5 Test of Variables of Attention variables, the intervention group scored higher than the controls on both the visual and auditory tasks (all P < .05). Because the intervention was delivered as a package, a limitation is that we cannot pinpoint the individual contribution of each component (nutrition, hygiene, and stimulation) to the developmental benefits.

CONCLUSIONS

The intervention group consistently scored markedly higher on both neuropsychological tests. Thus, even 8 years after the original maternal education intervention, the developmental benefits that we observed at child age of 1, 2, and 3 years, were sustained.

Association of ultraprocessed foods consumption and cognitive function among children aged 4-7 years: a cross-sectional data analysis

Background

Sugar-sweetened beverage (SSB) consumption has shown associations with cognitive function in preschool children, but effects of other ultraprocessed foods consumption are rarely discussed in China. This study aimed to investigate the relationship between ultraprocessed food consumption and cognitive function among preschool children in China.

Methods

A total of 325 children aged 4-7 years were included from Guangxi Zhuang Birth Cohort in Guangxi Zhuang Autonomous Region, China. Face-to-face interviews with parents using the Food Frequency Questionnaire (FFQ) was conducted to investigate the status of seven ultraprocessed foods consumption (i.e., chocolate, biscuits, candy, fast-food, ice cream, SSBs, and sweet bakery products). The mandarin-language version of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI, Fourth Edition) was applied to assess the cognitive function of children. Multiple linear and logistic regression models were used to assess the associations between ultraprocessed food consumption and the full-scale intelligence quotient (FSIQ) and different domains and risk of cognitive deficit, respectively.

Results

We found that frequent consumption of candy (β = -3.34, 95% CI: -5.62∼-1.06; p = 0.004) and sweet bakery products (β = -2.77, 95% CI: -5.58∼0.04; p = 0.054) were significant associated with decreased FSIQ scores in the linear regression models. However, only frequent consumption of candy was statistically significantly associated with an increased risk of cognitive deficit (OR = 2.05, 95% CI: 1.11∼3.79; p = 0.023) in the logistic regression models. For the different domains, we found frequent consumption of candy (β = -3.85, 95% CI: -6.28∼-1.43; p = 0.002) and sweet bakery products (β = -3.48, 95% CI: -6.47∼-0.49; p = 0.023) was also significantly associated with lower Verbal Comprehension Index (VCI). When combining the seven ultraprocessed foods, we found children who frequently consumed more than two kinds of ultraprocessed foods had a significant decrease of VCI scores (β = -2.66; 95% CI: -5.12∼-0.19; p = 0.035) too.

Conclusion

Our results suggested that frequent consumption of individual (candy and sweet bakery products) and multiple ultraprocessed foods may decrease VCI scores and thereby impact cognitive function in children aged 4-7 years.