Humans eat a variety of roots, and some of the most popular ones are carrots, cassava, sweet potatoes and beets. Radishes, East Asian giant radishes, parsnips and rutabagas are some other commonly consumed root vegetables.
Root vegetables are very important dietary components in the developing world. Without the capacity to grow corn, rice or wheat, many subsistence cultures depend heavily on these high-calorie vegetables. For example, cassava is an important carbohydrate in central Africa. According to the Food and Agriculture Organization of the United Nations, cassava is the third most important carbohydrate grown in the tropics, trailing only rice and corn. The primary reason that root vegetables work well for this purpose is that plants store energy resources in their roots. Most of this energy is stored in the form of complex carbohydrates or starches.
In addition to the ?true? root vegetables, many other foods grow underground and have somewhat similar characteristics. Potatoes, Jerusalem artichokes and yams are tubers, while ginseng and ginger are both rhizomes. In culinary contexts, tubers and rhizomes are classified as root vegetables. However, botanists classify them as modified stems and do not consider them ?true? root vegetables. Bulbs, such as onions, shallots, fennel and garlic, are not ?true? root vegetables by botanical standards either, but they are often considered root vegetables by chefs.