interdictions" (), 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 (; 621–713) compiled the first work entirely devoted to the therapeutic value of food: the Materia Dietetica (). This work has not survived, but it was 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. Later history An abundant literature developed in China around the medicinal uses of food. A mid-ninth-century work, now lost, called Candid Views of a Nutritionist-Physician () discussed how food could treat various disorders, while several works from the Song dynasty (960–1279) explained how to feed the elderly to extend their life. In the early 14th century, Hu Sihui, who served as Grand Dietician () at the court of the Mongol Yuan dynasty (1260–1368), compiled a treatise called Yinshan zhengyao, or Proper and Essential Things for the Emperor's Food and Drink (), which is still recognized in China as a classic of both materia medica and materia dietetica. Influenced by the culinary and medical traditions of the Turko-Islamic world and integrating Mongol food stuffs like mutton into its recipes, Hu's treatise interpreted the effects of food according to the scheme of correspondences between the five phases that had recently been systematized by northern Chinese medical writers of the Jin dynasty (1115–1234) and Yuan eras. Before that period, food materials had not yet been comprehensively assigned to the five flavors systematically correlated with specific internal organs and therapeutic effects. Chinese understandings of the therapeutic effects of food were influential in East Asia. Cited in Japanese works as early as the 10th century, Chinese dietary works shaped Korean literature on food well into the Joseon period (1392–1897). In the late 17th and early 18th centuries, the imperial court of the Qing dynasty (1644–1912) ordered several works on Chinese food therapy translated into Manchu. Main tenets Although the precepts of Chinese food therapy are neither systematic nor identical