In traditional Chinese philosophy, natural phenomena can be categorized into 5 elements: wood, fire, earth, metal and water. In human body, all five elements are represented because they correspond to the five major organs: kidneys, liver, heart, stomach and lungs. As for diet, there is a useful relationship between the colors of food, the five elements, and corresponding body systems. Green foods nourish the liver; yellow and orange foods nourish the spleen and stomach; red foods nourish the heart; white foods nourish the lung, black or dark blue foods nourish the kidneys. So, a person with weak digestion should include plenty of yellow and orange foods, such as sweet potatoes and winter squashes, as they bear the colors corresponding to the earth element or the spleen. One with heart weakness would do well by taking more red foods, such as tomatoes and hawthorn berries, as red corresponds to the five elements and the heart organ. Chinese herbalists believe that they need to know the state of the five elements in their patients to give them proper treatment. A deficiency or an excess of an element can lead to illness. It is self-explanatory to say that practitioners of traditional Chinese medicine rely on the “Five Elements Theory” to explain the relationships between body organs and the outside environment.