Objectives: Arid pastoralism is often understood as an adaptive strategy to marginal environments. As pastoralists become increasingly market integrated, novel dietary preferences and access to low quality market foods can erode traditional diets. These market-based dietary shifts are particularly problematic during sustained drought, where reductions in traditional foods make pastoralists increasingly reliant on a cash economy. Among the Himba of the Kunene region in Namibia, colonial policies prohibiting access to livestock markets inhibit access to a cash-based economy, leaving them vulnerable to food insecurity when nontraditional foods are needed to supplement traditional lifeways during drought. To understand the impacts of long-term drought on diet and food insecurity, we collected longitudinal survey data on diet breadth and food insecurity across 4 years during a multi-year drought.

Methods: Participants completed a five-item food insecurity survey and recalled diet breadth survey over the course of 4 years (N = 191-234). Additionally, women completed a short survey of recent stressors, including health and resource stressors (N = 127). We used a set of multilevel models to estimate changes in food insecurity items and diet breadth changes over the course of the study period.

Results: Multilevel models predicted score outcomes, as well as individual item responses, by year of data collection. Results indicate a 43% increase in average food insecurity and a 15% decline in average diet breadth over the study period. Dietary recall indicates that drought caused a reduction in sour milk intake, and an increase in nontraditional foods, but no change in meat or maize consumption.

Conclusions: Sustained drought in the Kunene region is having long-term impacts on food insecurity, which could result in dietary shifts that outlast the current period of drought. We consider the implications of this change, especially as it relates to increasing market integration and reliance on a cash-based over a subsistence-based economy.