People shouldn’t go hungry. Not because of someone’s hopeful wish, but because the world produces enough calories to go around. Each day, farmers grow 2,800 calories per person on the planet, according to the U.N. Food and Agriculture Organization (FAO). That’s enough to surpass the recommended intake of 2,100 daily calories per person—and enough to support a population inching toward nine billion, and then ten billion. So why do 805 million people still have too little to eat? To start with, it’s important to understand the difference between hunger and undernourishment. People all over the world go hungry, even for just a few hours, when they don’t have enough to eat. Hunger is a physical condition marked by stomach pangs and general fatigue. Undernourishment is a more chronic condition than hunger. Undernourishment affects communities, and even entire countries and regions. Measuring Undernourishment Each year, the FAO measures undernourishment around the world. “What we try to do is come up with a comprehensive picture of food insecurity,” says FAO economist Josef Schmidhuber. The process is never simple. In countries most at need, development agencies find it hard to get food in and data out. Food often doesn’t get to the people who need it. Some of these people are isolated in rural communities, while others live in politically unstable countries or areas ravaged by natural disasters. Africa has the highest rate of undernourishment. In the Central African Republic, where 38 percent of people are undernourished, an ongoing civil war has led to widespread displacement, which leads to disruptions in the food supply and distribution. The culprit in Zambia (48 percent undernourished) is infrastructure: Less than 20 percent of the population has access to a durable road. Asia has the most undernourished people. According to FAO researchers, parts of Africa and Asia are plagued by a lack of income, poor agricultural development and few social safety nets. North Korea may be the best example of a country with a political climate that limits trade and food aid. No country has it worse than Haiti, however. Even though the Western Hemisphere has almost uniformly reduced undernourishment over the past 20 years, the island nation has been relentlessly attacked by natural hazards and political instability. An earthquake in 2010, followed by several hurricanes in 2012 and a drought in 2014 have limited Haiti’s capacity to nourish its population. There is some good news: Since 1990, the overall number of undernourished people around the world has gone down—that means 209 million fewer undernourished people. Solving World Undernourishment Ultimately, solving world undernourishment comes with diminishing returns. The more progress you make, the more challenging the remaining work becomes. As places like sub-Saharan Africa increase their production of food staples, they then need to focus on distributing it to the people who need it most. Many regions lack infrastructure such as roads and bridges that can accommodate trucks carrying food. So, someone looking to alleviate world hunger doesn’t only need to focus on food, but on building roads and more secure buildings. Stable governments can help ensure fewer people go hungry. And when a country’s economy grows, almost everyone is better off.