Malnutrition stems from two crucial shortages: the land to grow food and the money to buy food. Many factors contribute to these two issues, from poor growing conditions to lack of adequate transportation infrastructure to political and economic unrest. These factors tie in closely to the concept of food security. If a region has food security, it means food is available, people have access to that food and people know how to leverage that food (along with water and sanitation) to meet their health needs.
Many factors can affect food security, leading to malnutrition, or even famine in turn. Natural disasters such as drought, crop blight, cold spells and flooding often contribute. Such events -- along with political conflicts and other major disruptions -- can cause a phenomenon sometimes referred to as livelihood shock. The disruption is so profound that a population cannot quickly recover from the immediate ramifications and the situation spirals out of control. Such was the case during the Great Famine that took place in Ireland during the late 1840s.
Other contributors to famine include economic and political dynamics, both regional and global. For example, when food security starts to stutter in one nation or region, others with more money may stockpile what is available to protect their own populations, thus driving up prices for those already struggling. Similarly, nations with food to export may lock their borders, creating further troubles in terms of supply and demand.
In this way, poverty is a big part of food stability. While there may be enough food in the world to feed everyone, the market often impedes food from flowing to all those who need it. It's also a positive feedback cycle: People who don't get enough to eat are more likely to perform poorly or lack resources to better their situation, which in turn locks them into poverty, and they continue to not get enough to eat.
On the next page, we'll examine what happens during a famine.