One of the most urgent challenges we face in the next several decades is feeding a growing world population without irreparably damaging Earth’s land, air and water systems. Nearly 800 million people worldwide are undernourished today. The U.N.‘s Sustainable Development Goals call for ending hunger and achieving food security by 2030.

The world is making progress in reducing hunger, but we have further to go. The annual Global Hunger Index, produced by the International Food Policy Research Institute, scores nations based on the proportion of their total population that is undernourished and several metrics that focus on children. Since 2000, the GHI has decreased across all regions of the world, but 50 countries – mainly in sub-Saharan Africa and South Asia – still have alarming or severe hunger rates.

At the Global Landscapes Initiative in the University of Minnesota’s Institute on the Environment, our research focuses on increasing global food security while reducing harmful impacts from agriculture to Earth’s natural resources. We have found that one key strategy to combating food insecurity – lack of access to nutritious foods – is increasing food production on small farms.

There are tremendous opportunities to increase yields throughout South Asia and sub-Saharan Africa. Increasing yields through new farming practices could triple maize production in sub-Saharan Africa and increase wheat and rice production in South Asia by about 50 percent. Gains on this scale could dramatically reduce hunger and food insecurity in some of the most vulnerable nations in the world.

The U.N. estimates that more than 70 percent of the world’s food-insecure people live in rural areas of developing countries where farming is typically the dominant land use and source of income. My colleague Leah Samberg recently led a study that combined household census data with satellite-derived land-cover data of croplands and pastures to map the average farm size in regions of the world dominated by smallholder farmers. In many countries with alarming and severe GHI scores, the average farm size is less than five hectares, or about 12 acres.

Small farms dominate South Asia and sub-Saharan Africa, where the hunger index scores are highest. These farms currently produce 41 percent of global calories from croplands, and the majority of crops that are essential for food security in many regions, including rice, cassava, groundnuts and millet.

Read more: Mind the gaps: Reducing hunger by improving yields on small farms