Feasibility and Impact of School-Based Nutrition Education Interventions on the Diets of Adolescent Girls in Ethiopia: A Non-Masked, Cluster-Randomised, Controlled Trial

"[I]f designed to address behavioural determinants such as knowledge, attitudes, and beliefs, in-school nutrition education interventions might be effective in improving diversified food or specific food consumption among adolescents, even in rural and food insecure contexts."

Adolescence is a critical period of physical and psychological development, especially for girls, because poor nutrition can affect their wellbeing as well as that of their children. Global evidence shows that multisectoral and multifaceted strategies offer the most promise. This non-masked, cluster-randomised controlled trial (RCT) evaluates a package of school-based nutrition education interventions coupled with community and health platform-based interventions and capacity building of school staff and service providers to improve the diet of girls aged 10-14 years in Ethiopia.

In 2019 in Ethiopia, Alive & Thrive, or A&T (a global initiative) developed a package of locally tailored adolescent nutrition interventions to be delivered in school, household, and community settings. The core interventions involved nutrition education that entailed 6 activities: flag ceremonies, classroom lessons, school club meetings, peer mentoring sessions, body mass index (BMI) measurement and counselling sessions, and parent-teacher meetings. An action point included in all intervention components for adolescent girls was to share what they heard or learned with their parents, so that parent-teacher meetings were not the only source of nutrition information for parents. Each of the intervention components was designed to address information about locally available foods that make up a diverse diet, particularly specific food groups with large room for improvement based on formative study, and to provide motivation to acquire and consume a diverse diet. The school-based interventions were delivered by school principals and teachers, who received training about adolescent nutrition and how to implement classroom dialogue and hands-on activities to engage adolescents and parents. (Secondarily, though not evaluated here, health extension workers and influential community actors were encouraged to deliver information about adolescent nutrition to families and the broader community during health facility and home visits for other health services and at community gatherings.)

For the study, primary schools (clusters) in the Southern Nations, Nationalities, and People's Region and Somali region of Ethiopia were randomly allocated to the intervention group (A&T activities as described above, 27 schools) or the control group (standard academic curriculum on health and nutrition, 27 schools). Duration of the school-based interventions was 4 months, and the key messages were related to dietary diversity (eating a variety of foods), energy adequacy (eating breakfast and healthy snacks), and healthy food choices (avoiding junk foods). Adolescent girls were eligible for participation if aged 10-14 years and enrolled in grades 4-8 in a study school. Data were collected with 2 independent cross-sectional surveys: baseline before the start of implementation and endline 1.5 years later. The primary outcome of impact was dietary diversity score, defined as the number of food groups (out of 10) consumed over the previous 24 hours using a list-based method, and minimum dietary diversity, defined as the proportion of girls who consumed foods from at least 5 of the 10 food groups, in the intention-to-treat population. The researchers also assessed intervention exposure as a measure of feasibility.

Between March 22 and April 29, 2021, 536 adolescent girls participated in the endline survey (270 in the intervention group and 266 in the control group). At endline, the dietary diversity score was 5.37 (standard deviation (SD) 1.66) food groups in the intervention group and 3.98 (1.43) food groups in the control group (adjusted mean difference 1.33, 95% confidence interval (CI) 0.90-1.75, p<0.0001). Increased minimum dietary diversity was also associated with the intervention (182 [67%] of 270 in the intervention group vs 76 [29%] of 266 in the control group; adjusted odds ratio 5.37 [95% CI 3.04-9.50], p<0.0001).

As Table 3 in the paper shows, both adolescent girls and their parents in the intervention group had higher knowledge at endline than those in the control group about dietary diversity, meal frequency, and consumption of unhealthy foods. Adolescent girls had more knowledge about meal frequency than about dietary diversity or avoiding unhealthy foods; similar patterns were observed among their parents. Also, there was evidence of improved food preparation by parents for their adolescent daughters and their home food environment in the intervention group at endline.

Despite an intervention effect on the consumption of other sweets, more than half of the adolescent girls reported consuming junk food, with no differences between study groups. Knowledge about avoiding junk food as part of good nutrition improved among adolescent girls and their parents between study groups, but knowledge did not translate into practice. This may be due to the fact that, at endline, nearly all study schools had at least 1 food vendor within a 1-minute walking distance, mainly selling sweets and soda or sugar-sweetened beverages, and about a quarter of adolescent girls had seen or heard a food advertisement in the past 3 months. Thus, other intervention strategies might be required to change food environments, such as the provision or product placement of healthy food or snack options at or near schools, and behaviours particularly related to consumption of junk foods.

The school-based intervention was able to reach adolescent girls and their parents: 256 (95%) of 270 adolescent girls in the intervention group were exposed to at least 1 of the 5 in-school intervention components, and 145 (54%) of 270 parents of adolescent girls in the intervention group were exposed to discussions about nutrition at parents' meetings at schools. Adolescent girls in the intervention group most commonly received nutrition information via flag ceremonies (230 [85%]), classroom lessons (226 [84%]), and BMI measurements (197 [73%]). Exposure to at least 2 intervention components was associated with substantially higher odds of achieving minimum dietary diversity and high meal frequency among adolescent girls.

In conclusion, a package of nutrition education interventions delivered in primary schools in Ethiopia was feasible to implement and effective in improving adolescent girls' dietary practices.