Improved skills and rural-urban location of labor are generally implicit or ignored in food security projections. We analyze alternative labor supply assumptions for four contrasting scenarios. Changing skill levels and urbanization reverses a decrease in food prices and improves instead of worsens within country income inequality. It however slows the decrease in number of people with less than 2500 calories a day available, and increases the environmental impact of agriculture. With urbanization, observed net income benefits of higher food prices for the poor may no longer hold in the future. Explicitly addressing demographic change is thus key in projections guiding policymakers to address the unequal impacts of food security, combat climate change and promote sustainable food production.