Most food originates from several different species of plants. Some food is obtained directly from the plants themselves; but even the animals used as food sources are raised on feed that derives from plants. Cereal grain is a popular food source that provides more food worldwide than any other type of crop.
Sustainable Food sources are extremely important because of the world’s increasing population and decreasing land space. The average community grocery stores have about a three day supply of food. Their is a also a dependency on cheap fossil fuels and transportation infrastructure that will not be sustainable. Especially with the impending constraints on resources. The current model of food cannot be sustained as resources become constrained. CO2 emissions from raising cattle alone is having a critical impact on soil, air, water, and human health.
The World Health Organization defines food security to be when "all people at all times have access to sufficient, safe, nutritious food to maintain a healthy and active life." As the world continues to grow in population, it's important to rememeber finding sustainable food sources are of the utmost importance!