Introduction

Beans are the fourth most important source of protein in tropical America and surpass two popular regional root crops—potato and cassava–as a source of calories. Throughout the region the common bean is known as the "poor man's meat." Latin America is the most important bean producing region with 8 million hectares. 

Dry beans are a vital staple in sub-Saharan Africa providing the main source of dietary protein for more than 70 million people. Production is concentrated in densely populated eastern Africa, the lakes region, and highlands of southern Africa.

Nutritionists characterize the common bean as a nearly perfect food because of its high protein content and generous amounts of fiber, complex carbohydrates and other nutrients. A single serving (1 cup or 240 ml) of beans provides at least half the recommended daily allowance of–folate–a B vitamin that is especially important for pregnant women to prevent birth defects. It also supplies 25 to 30 percent of the recommended levels of iron and meets 25 percent of the daily requirement of magnesium and copper as well as 15 percent of the potassium and zinc requirement.