Influence of diet quality on nutritional status of school-aged children and adolescents in Zanzibar, Tanzania.

BACKGROUND

Malnutrition among young children and adolescents poses a serious health challenge in developing countries which results in many health problems during adulthood. Poor diet quality is known as the root cause of malnutrition which is caused by unhealthy food choices and bad eating habits among young children and adolescents. However, limited evidence is available on diet quality and its association with nutrition status among young children and adolescents in Zanzibar. This study examined the diet quality and its relationship with the nutritional status of school-aged children and adolescents in Zanzibar.

METHODS

Data for this study was obtained from the cross-sectional survey of School Health and Nutrition (SHN) conducted in Zanzibar. The survey recruited children aged 5-19 years from 93 schools in Zanzibar. A seven-day food frequency questionnaire (FFQ) was used to assess dietary intake. Prime Dietary Quality Score (PDQS) consisted of 21 food groups was then constructed to assess the diet quality of school-aged children and adolescents. Body mass index (BMI-for-age Z-score) was used as the indicator of nutrition status. Both linear and logistic regression analysis techniques were used to determine the associations between BMI and PDQS.

RESULTS

A total data of 2,556 children were enrolled in the survey. The prevalence of thinness was 8.1%, normal 82.1%, overweight 7.2% and obesity 2.6%. The mean (SD) PDQS score was 18.8 (3.2) which ranged from 8 to 33. Consumptions of green leafy vegetables (49.3%), yellow or red fruits (37.8%), legumes (38.3%), fish (36.3%), and vegetable oil (31.5%) were up to three times per week, whereas consumptions of white vegetables (77.3%), cooked vegetables (32.6%), citrus fruits (66.8%), other types of fruits (66.2%), nuts (46.4%), poultry (49.6%), whole grains (61%) and eggs (67.8%) were less than once per week. In terms of unhealthy foods, eating fried foods was reported by 26.3% up to three times per week, and 31.5% reported consuming sweets and ice cream up to three times in the past week. High PDQS was significantly associated with a reduction in BMI of children (p< 0.005). For each unit increase in the consumption of unhealthy foods such as fried foods, cooked vegetables and refined grains there is a significant increase in BMI. The odds of being obese decrease significantly as diet quality increases from the first to third quintile of PDQS (AOR = 0.2, 0.04-0.89 95% CI, p = 0.035).

CONCLUSION

Consumption of high quality diet was found to be associated with a reduction in excessive weight among school-aged children and adolescents in Zanzibar. There is a need for interventions targeting to reduce unhealthy food consumption in school environment. Further research should be conducted to assess diet quality using PDQS among young children and adolescents.