A Nutrition-Sensitive Agroecology Intervention in Rural Tanzania Increases Children's Dietary Diversity and Household Food Security But Does Not Change Child Anthropometry: Results from a Cluster-Randomized Trial.

BACKGROUND: There are urgent calls for the transformation of agriculture and food systems to address human and planetary health issues. Nutrition-sensitive agriculture and agroecology promise interconnected solutions to these challenges, but evidence of their impact has been limited. OBJECTIVES: In a cluster-randomized trial (NCT02761876), we examined whether a nutrition-sensitive agroecology intervention in rural Tanzania could improve children's dietary diversity. Secondary outcomes were food insecurity and child anthropometry. We also posited that such an intervention would improve sustainable agricultural practices (e.g., agrobiodiversity, intercropping), women's empowerment (e.g., participation in decision making, time use), and women's well-being (e.g., dietary diversity, depression). METHODS: Food-insecure smallholder farmers with children aged <1 y from 20 villages in Singida, Tanzania, were invited to participate. Villages were paired and publicly randomized; control villages received the intervention after 2 y. One man and 1 woman "mentor farmer" were elected from each intervention village to lead their peers in agroecological learning on topics including legume intensification, nutrition, and women's empowerment. Impact was estimated using longitudinal difference-in-differences fixed-effects regression analyses. RESULTS: A total of 591 households (intervention: n = 296; control: n = 295) were enrolled; 90.0% were retained to study end. After 2 growing seasons, the intervention improved children's dietary diversity score by 0.57 food groups (out of 7; P < 0.01), and the percentage of children achieving minimum dietary diversity (≥4 food groups) increased by 9.9 percentage points during the postharvest season. The intervention significantly reduced household food insecurity but had no significant impact on child anthropometry. The intervention also improved a range of sustainable agriculture, women's empowerment, and women's well-being outcomes. CONCLUSIONS: The magnitude of the intervention's impacts was similar to or larger than that of other nutrition-sensitive interventions that provided more substantial inputs but were not agroecologically focused. These data suggest the untapped potential for nutrition-sensitive agroecological approaches to achieve human health while promoting sustainable agricultural practices.

Food security mediates the decrease in women's depressive symptoms in a participatory nutrition-sensitive agroecology intervention in rural Tanzania.

OBJECTIVE: To investigate if food security mediated the impact of a nutrition-sensitive agroecology intervention on women's depressive symptoms. DESIGN: We used annual longitudinal data (four time points) from a cluster-randomised effectiveness trial of a participatory nutrition-sensitive agroecology intervention, the Singida Nutrition and Agroecology Project. Structural equation modelling estimation of total, natural direct and natural indirect effects was used to investigate food security's role in the intervention's impact on women's risk of probable depression (Center for Epidemiologic Studies Depression Scale > 17) across 3 years. SETTING: Rural Singida, Tanzania. PARTICIPANTS: 548 food insecure, married, smallholder women farmers with children < 1 year old at baseline. RESULTS: At baseline, one-third of the women in each group had probable depression (Control: 32·0 %, Intervention: 31·9 %, P difference = 0·97). The intervention lowered the odds of probable depression by 43 % (OR = 0·57, 95 % CI: 0·43, 0·70). Differences in food insecurity explained approximately 10 percentage points of the effects of the intervention on odds of probable depression (OR = 0·90, 95 % CI: 0·83, 0·95). CONCLUSIONS: This is the first evidence of the strong, positive effect that lowering food insecurity has on reducing women's depressive symptoms. Nutrition-sensitive agricultural interventions can have broader impacts than previously demonstrated, i.e. improvements in mental health; changes in food security play an important causal role in this pathway. As such, these data suggest participatory nutrition-sensitive agroecology interventions have the potential to be an accessible method of improving women's well-being in farming communities.

A Mixed Methods Exploration of the Role of Participation in a Nutrition-Sensitive Agroecology Intervention in Rural Tanzania.

Background: Participation is key to the successful implementation of nutrition-related interventions, but it has been relatively overlooked. Objective: We sought to describe participation intensity among smallholder farmers in a randomized nutrition-sensitive agroecology study in rural Tanzania. We explored the association between baseline characteristics and overall participation intensity (quantitatively at the individual level and qualitatively at the group level), the association of participation intensity with 2 process indicators, and the association between participation intensity and key study outcomes. Methods: Data came from 7 rounds of surveys with 295 women and 267 men across 29 months and 2 rounds of semi-structured interviews with the 20 "mentor farmers" who delivered the intervention. Participation intensity was based on the number of months of attendance at village-level project meetings or household visits (range: 0-29). Multivariable models of participation were built. Results: Women and men participated for 17.5 ± 7.2 and 13.6 ± 8.3 months, respectively. Participation intensity followed 1 latent trajectory: initially low, with a sharp increase after month 7, and plateaued after the first year. At baseline, higher participation intensity was associated with older age, higher education, level of women's empowerment, being in the middle quintile of wealth, and qualitatively, village residence. Higher participation intensity was associated with 2 process indicators - better recall of topics discussed during meetings and greater knowledge about key agroecological methods. High participation intensity was positively associated with increased use of sustainable agricultural practices among all participants, and among women, with husband's involvement in household tasks and child's dietary diversity score. Conclusions: Participation intensity covaried with key study outcomes, suggesting the value of increased attention to implementation in nutrition-related programs for providing insights into drivers of impact. We hope that investigations of participation, including participation intensity, will become more widespread so that intervention impacts, or lack thereof, can be better understood.