Infrastructures of Appetite: Mega Projects, Food Security, and Dietary Transitions in Maasai Pastoralist Tanzania

Mega infrastructure projects are rapidly transforming livelihoods and food systems across East Africa. Pastoralist communities, traditionally reliant on livestock-based diets, face distinct challenges as infrastructure development reduces grazing land and disrupts established food practices. This study examines how the Standard Gauge Railway (SGR) has reshaped diets among Maasai households in Kilosa District, Tanzania. Drawing on qualitative methods namely interviews, focus group discussions, and participant observation in two selected pastoralist settlements, the analysis applies nutrition transition theory to link macro-level infrastructural change to household food choices. Findings show that income from SGRrelated employment improved access to market foods such as rice, maize, and vegetables, while reduced herd size lowered the daily availability of milk and blood, long-standing staples of Maasai nutrition and identity. Women emerged as central actors in managing this transition, adapting food preparation and blending traditional with new ingredients. However, reliance on market foods introduced new vulnerabilities to price fluctuations and income instability. The paper concludes that dietary transitions in Maasai communities are non-linear, combining resilience with risk. While infrastructure-driven change enhances dietary diversity, it simultaneously threatens nutrient sufficiency and cultural heritage. Policy responses should safeguard livestock-based food systems, strengthen gender-responsive nutrition strategies, and stabilize rural markets to support hybrid models that balance tradition and innovation..