Traditional Chinese medicine (TCM) teaches that humans should eat all kinds of foods, similar to the modern idea of a balanced diet. The plants-only diets now associated with vegetarianism are not mentioned in the ancient Chinese literature on proper eating.
In fact, some passages seem to specifically endorse diets that include at least some meat. For instance, the Huang Di Nei Jing Su Wen - the first volume of the Yellow Emperor's Classic of Internal Medicine - says: 'When one takes the tastes of cereal, fruit, meat, and vegetable in combination, it can invigorate the essence and nourish the vital energy.'
The book, which dates back to the late Warring States Period (475BC-221BC), also says that 'medicines are used to fight the evils, cereals are used to nourish the body, and fruits, meats and vegetables to aid the efforts - all the tastes working together to reinforce the vital qi and essence'.
Shen Nong's Herbal Classic, written in the Eastern Han dynasty (AD25-AD220), also mentions meats, such as chicken and wild goose fat, among foods that can improve health and delay ageing.
That said, a plants-only diet can still be consistent with TCM, says registered Chinese medicine practitioner Vincent Lee Yu-ming, a Hongkonger who's doing a PhD in Chinese medical science at the Beijing University of Chinese Medicine.
'Meat can be beneficial, but if you eat too much of it you usually get diseases such as stroke, diabetes, asthma, obesity - these were indicated some 2,000 years ago,' Lee says. 'In fact, in ancient times, most people in China had mainly vegetarian diets as it was difficult to find meat to eat.'