Limited dietary diversity and consumption of ultra-processed and deep-fried foods among adolescents in rural Bangladesh : uncovering the two faces of suboptimal diet

Abstract: Background: With an estimated number of 1.2 billion in the world, adolescents represent a major transformative force in global health. Optimum adolescent nutrition is increasingly important for scaling up population health gains in low- and middle-income countries (LMICs) of South Asia. Nevertheless, little is known about the gender and socio-economic stratification of diets consumed by rural adolescents in these countries. The aim of this project was to understand the gender and socio-economic stratification of their diet with a dual, descriptive-analytic focus on dietary diversity (DD) and consumption of ultra-processed and deep-fried foods.Methods: This thesis builds upon cross-sectional analyses of data collected during 15-year follow-up of the MINIMat (Maternal and Infant Nutrition Interventions in Matlab) trial, from September 2017 to June 2019. Data on dietary and socio-demographic variables were collected through household survey; using a pre-tested, structured questionnaire. A single, 24-hour recall was employed to assess consumption of staples and non-staples arranged in 10 groups, ultra-processed foods (UPF) in four groups, and of one group of deep-fried foods. Data were analyzed using logistic regression models. The analytic sample comprised 2463 adolescents.Results: The prevalence of inadequate DD was 42.3% (40.3-44.2). Consumption of dark green leafy vegetables, vitamin A-rich fruits and vegetables, and animal-source foods–except fish–appeared low. The proportions of adolescents consuming meat, egg and dairy were higher among those from the richest households than those from the poorest households, and among boys than girls. Belonging to the poorest households (adjusted odds ratio (aOR): 1.59; 95% confidence interval (CI): 1.27-2.00) and the food insecure households (aOR: 1.34; 95% CI: 1.13-1.59), and attaining secondary education (aOR: 1.38; 95% CI: 1.11-1.71) were positively associated with inadequate DD. Adolescents having mothers with secondary education or above had lower odds of inadequate DD (aOR: 0.76; 95% CI: 0.60-0.96). Gender was not an independent predictor of inadequate DD.Approximately 83% (81.5-84.4) adolescents reportedly consumed at least one ultra-processed or deep-fried food in the 24 hours preceding the survey. Packaged confectioneries were the most consumed and sugar-sweetened beverages (SSB) the least consumed UPF group. Boys had greater odds of consumption than girls for all UPF groups and deep-fried foods. The association was strongest for SSB (aOR: 2.57; 95% CI: 1.97, 3.37), followed by deep-fried foods (aOR 1.96; 95% CI: 1.66, 2.32). Belonging to the richest households was associated with consumption of ready-to-eat foods (aOR 1.55; 95% CI: 1.12-2.16) and of SSB (aOR: 1.44; 95% CI: 1.02-2.03). Adolescents with higher educational attainment had lower odds of consuming SSB (aOR 0.73; 95% CI: 0.54-0.98).Conclusion: The studies presented compelling evidence of limited DD concurrent with emergent consumption of ultra-processed and deep-fried foods in a rural cohort of adolescents. Inadequate DD was more likely among those from the poorest and the food insecure households. For ultra-processed and deep-fried foods, gender association persisted across the food groups with boys having a greater likelihood of consumption than girls. Wealth status influenced consumption of “instant” foods and SSB only. This suboptimal dietary pattern may place the adolescents at heightened risk of different forms of malnutrition.