How does adopting hybrid maize affect dietary diversity on family farms? Micro-evidence from Zambia

•We test the association between planting hybrid seed and diet diversity in Zambia.•We measure diet diversity in four ways, with a focus on sources of vitamin A.•We estimate instrumental variables, Poisson, and ordered logit regression models.•Women in maize-growing households that plant hybrid seed have more diverse diets. Maize dominates as a staple food in Zambia, where the government has for many years promoted hybrid seed use in order to enhance the food self-sufficiency of poor rural families. Despite the policy importance of household nutrition in Zambia, we are not aware of any recent analyses that have related the use of hybrid seed to diets among smallholder maize growers. Previous research has demonstrated a linkage between indices of dietary diversity and healthy diets among women and children. We estimate two-stage, instrumental variables, Poisson, and ordered logit regression models to test the association between hybrid seed use and four indicators of dietary diversity: food group diversity (24-h), vitamin A diversity (7-day), food frequency (7-day), and frequency of consuming foods fortified with vitamin A (7-day). Results are robust to econometric method and indicator: women interviewed in maize-growing households that plant hybrid seed have more diverse diets.