“A doctor must first understand the origin of a patient’s sickness to know how to attack it, and treat it with food. If that fails, use medicine.”
–Sun Simiao, 7th C
Since antiquity, Chinese have regarded food as not just nourishing, but medicinal. An extensive and complex system of using food to combat illness and maintain health has been in constant use for many centuries—only it has nothing to do with nutrients, vitamins, enzymes, Ph balance, or anything else about food properties understood by Western science. It revolves instead around the flavors of foods, the properties of foods, and how their energies move in the body. The Chinese system, based on long experience and deduction, comprises a philosophy that is its own unified field theory of food and health. In some ways it seems to have anticipated subsequent medical science—for example, many treatments for goiter include seaweed and kelp, natural sources of iodine. In other ways, it does not mesh meaningfully with the medicine of the West: why should broad bean relieve edema, for example, and water chestnut help with diabetes? Perhaps it is possible that micronutrients found in these foods play a compounding role, just as there is a chance that the manner of consuming the food makes a difference. Many prescriptions for using foods in the service of Traditional Chinese Medicine involve creating a broth or decoction according to specific instructions.
The categories below—the flavors of foods, the energies of foods, the movements of foods—do not refer to how food feels or tastes (despite the word “flavor”), but to how it acts inside the body. These classifications measure the effects of foods, as these effects were traditionally understood.
The Five Flavors
Foods were thought to carry five basic flavors: sweet, sour, bitter, salty, and pungent. In some sources, the fifth flavor is called hot (peppery), instead of pungent. The most common flavor by far is sweet, for it includes not only fruits and obviously sweet things, but also fish, grain, and beef. Foods of the sweet flavor (Bamboo shoots, barley, tofu, eggplant) improve digestion. Sour foods (lemon, olive, red bean, litchi and tomato) are good for obstructing movement, and are thought to assist in relieving excessive perspiration, or stopping diarrhea. Bitter foods (hops, apricot seed, grapefruit peel, asparagus) bring down fever and release body fluids. Pungent foods (ginger, green onion, pepper, cinnamon) are believed to improve energy circulation. Salty foods (kelp, seaweed) relieve conditions of hardening, like swollen lymph nodes. These are only a few out of many examples. Countless foods can be classified, and utilized, in this way.
The Five Energies
The energy of a food is its ability to cause one kind of sensation or another in the body—to warm the body, say, or to cool it. The energies refer not to the food, but to its supposed causative power. (Example: tea is “cold”; it cools the body, even when it is drunk hot.) The five energies are hot, cold, warm, cool, and neutral. At its most basic level, the principle is simple: for a “hot” symptom, such as hives, consume a cooling food such as mung bean soup, or sugar. Similarly, if you have an overly warm or overly cool constitution, you can eat to correct it. Cold foods include crab, lettuce, cantaloupe, clams, and bitter gourd; cool ones encompass radish, spinach, and wheat, among many others. Examples of hot foods are pepper, soybean oil, and dried ginger, while “warm” foods like chicken, chestnut, coconut, coffee, fennel, mutton, leek, and star anise raise the temperature a little more gently. Finally, there is a long list of foods with neutral energy, such as oysters, peanuts, cabbage, carp, milk, potato, and yellow soybean. Yet these categories are not set in stone; they are really folkways, and can vary from one sub-group to another. For example, E.N. Andersen and Marja Andersen (1984) found that Cantonese and Malaysian Hokkien Chinese held opposing views about the cooling and warming effects of rice and congee.
Movement of Foods in the Body
Foods are thought to move inwards or outwards in the body; upward or downwards. Foods that move outward help to carry what is inside out, so these foods help someone to break a sweat and reduce a fever. Outward-moving foods are good for the body in summer, and they tend to be pungent or sweet. Green pepper, black pepper, and soybean oil are examples. Foods that push inward help reduce abdominal swelling, and thus move bowels. They are winter foods, with cold energy, like bitter gourd and clams. Foods with upward movement belong to spring; they tend to pull energy from the lower half of the body toward the top, so they are useful in conditions of prolapse. Upwards foods are pungent or sweet, with a hot energy (egg yolk, kohlrabi, kidney beans, apricot, beef, black fungus, fig, grape, and licorice.) Downwards foods relieve hiccups and vomiting, and are associated with autumn, as well as with cool, cold, or warm energies. Button mushrooms, apples, and egg whites are downward-moving examples.
Chinese dietary tradition recognizes six constitutional types: hot, cold, dry, damp, deficient, and excessive. Determining one’s constitutional type is at least partly intuitive: persons who tend to feel overheated and thirsty, and have flushed complexions, are likely to run hot. People with deficient constitutions tend to be weak and low-energy, while those with excessive constitutions display high energy and speak in loud high-pitched voices. Then there is the question of whether one is dry or damp. Most people, moreover, are not one pure constitutional type, but a combination of several aspects. In assessing a patient’s constitution with a view toward making dietary recommendations, a doctor of Traditional Chinese Medicine would consider many factors, including the tongue, the pulses (TCM takes twelve pulses), urine, stool, sleep patterns, symptoms, etc. The correlation of this assessment with the many possible ways of combining the flavors, energies, and movements of foods is complex, and a reminder that Chinese medicinal foodways are as much an art as a system.