Chinese food therapy

Chinese food therapy (, also called nutrition therapy and dietary therapy) is a mode of dieting rooted in Chinese understandings of the effects of food on the human organism, and centred on concepts such as eating in moderation. Its basic precepts are a mix of folk views and concepts drawn from Traditional Chinese medicine.

Food therapy has long been a common approach to health among Chinese people both in China and overseas, and was popularized for western readers in the 1990s with the publication of books like The Tao of Healthy Eating (= ) and The Wisdom of the Chinese Kitchen (= )., which also cites, , and

Origins
A number of ancient Chinese cookbooks and treatises on food (now lost) display an early Chinese interest in food, but no known focus on its medical value. The literature on "nourishing life" (yangsheng 養生) integrated advice on food within broader advice on how to attain immortality. Such books, however, are only precursors of "dietary therapy", because they did not systematically describe the effect of individual food items.

The earliest extant Chinese dietary text is a chapter of Sun Simiao's Prescriptions Worth a Thousand Gold (Qianjin Fang 千金方), which was completed in the 650s during the Tang dynasty. Sun's work contains the earliest known use of the term "food (or dietary) therapy" (shiliao). Sun stated that he wanted to present current knowledge about food so that people would first turn to food rather than drugs when suffering from an ailment. His chapter contains 154 entries divided into four sections – on fruits, vegetables, cereals, and meat – in which Sun explains the properties of individual foodstuffs with concepts borrowed from the Yellow Emperor's Inner Canon: qi, the viscera, vital essence (jing 精), and correspondences between the Five Phases, the "five flavors" (sour, bitter, sweet, pungent, and salty), and the five grains. He also set a large number of "dietary interdictions" (shijin 食禁), some based on calendrical notions (no water chestnuts in the 7th month), others on purported interactions between foods (no clear wine with horse meat) or between different flavors.

Sun Simiao's disciple Meng Shen (孟詵; 621–713) compiled the first work entirely devoted to the therapeutic value of food: the Materia Dietetica (Shiliao bencao 食療本草; lit., "food therapy materia medica"). This work has not survived, but it is quoted in later texts – like the 10th-century Japanese text Ishinpō – and a fragment of it has been found among the Dunhuang manuscripts. Surviving excerpts show that Meng gave less importance to dietary prohibitions than Sun, and that he provided information on how to prepare foodstuffs rather than just describe their properties. The works of Sun Simiao and Meng Shen established the genre of materia dietetica and shaped its development in the following centuries.

Precepts
Although the precepts of Chinese food therapy are neither systematic nor identical in all times and places, some basic concepts can be isolated. Food items are classified as "heating" (re 熱; "hot") or "cooling" (liang 涼; "cool"). Heating food is typically "high-calorie, subjected to high heat in cooking, spicy or bitter, or 'hot' in color (red, orange)", and includes red meat, innards, baked and deep-fried goods, and alcohol. They are to be avoided in the summer and can be used to treat "cold" illnesses like excessive pallor, watery feces, fatigue, chills, and low body temperature caused by a number of possible causes, including anemia. Green vegetables are the most typical cooling food, which is "low-calorie, watery, soothing or sour in taste, or 'cool' in color (whitish, green)". They are recommended for "hot" conditions: rashes, dryness or redness of skin, heartburns, and other "symptoms similar to those of a burn", but also sore throat, swollen gums, and constipation.