Bananas belong to the most popular and most eaten fruits in the world. They were first grown in tropical India and Southeast Asia over 4000 years ago. Arab merchants brought them to northern Africa and the Middle East. Portuguese navigators discovered bananas when they sailed down the Atlantic coast of Africa. From there they were brought to the Canary Islands, from where Spaniards took them to the New World. Although bananas grow like trees they are actually plants. They are made up of stalks that are covered with overlapping leaves. A stalk or stem can be about 30 cm thick. A banana plant can grow up to 6 meters in height. It has up to 20 long and wide leaves. Bananas hang in clusters, also called hands, from the plant. Each cluster can carry about 10 to 20 bananas. Bananas need good, well-drained soils, as well as a warm tropical climate with enough rainfall to grow. They are often cultivated on plantations, often with hundreds of workers who cultivate and harvest bananas for the world market. These large farms sell their products to large companies like, Chiquita and Dole. The first banana fruits can grow about a year after planting. Bananas are endangered by temperatures below zero and strong winds. Diseases, like the Panama disease, an infection of the soil, can completely destroy banana crops. Bananas are harvested while they are still green. In this state the banana's flesh is white and cannot be eaten. The green fruits are taken to the nearest port, where they are put on container ships with cooling containers on board. When the bananas arrive at their destination they are loaded onto trucks or railway cars and brought to sellers who store them in special ripening rooms. From this time on it takes bananas about five days to ripen and get the yellow colour and taste we all know. As the fruit ripens the flesh also becomes sweet. In many tropical regions of Africa, South America and Asia, bananas are a main food for the population. They have many nutrients that people need. In addition to 75% water, a banana contains sugar, proteins and vitamins. It gives you quick energy and can be digested fairly easily. Bananas belong to the healthiest foods in the world. They contain potassium, which can lower your blood pressure, prevent heart diseases and reduce the risk of a stroke. In the western world bananas are eaten as snacks in-between meals or together with cereals. In other countries they are used to make wine or beer.