Regional cultural differences vary greatly amongst the different regions of China, giving rise to the different styles of food. There are eight main regional cuisines, or Eight Great Traditions (八大菜系): Anhui, Cantonese, Fujian, Hunan, Jiangsu, Shandong, Sichuan, and Zhejiang. Among them, Cantonese, Sichuan, Shandong, and Huaiyang cuisine (a major style and even viewed as the representation of the entire Jiangsu cuisine) are often considered as the standouts of Chinese cuisine and due to their influence are proclaimed as the Four Great Traditions (四大菜系). Occasionally, Beijing cuisine and Shanghai cuisine are also cited along with the aforementioned eight regional styles as the Ten Great Traditions (十大菜系). There are also featured Buddhist and Muslim sub-cuisines within the greater Chinese cuisine, with an emphasis on vegetarian and halal-based diets respectively.
Pork is generally preferred over beef in Chinese cuisine due to economic, religious, and aesthetic reasons; swine are easy to feed and are not used for labour, and are so closely tied to the idea of domesticity that the character for "home" (家) depicts a pig under a roof. The colour of the meat and the fat of pork are regarded as more appetizing, while the taste and smell are described as sweeter and cleaner. It is also considered easier to digest. Buddhist cuisine restricts the use of meats and Chinese Islamic cuisine excludes pork.
Vegetarianism is not uncommon or unusual in China, though, as is the case in the West, it is only practiced by a relatively small proportion of the population. Most Chinese vegetarians are Buddhists, following the Buddhist teachings about minimizing suffering. Chinese vegetarian dishes often contain large varieties of vegetables (e.g. Bak Choy, shiitake mushroom, sprouts, corn) and some imitation meat. Such imitation meat is created mostly with soy protein and/or wheat gluten to imitate the texture, taste, and appearance of duck, chicken, or pork. Imitation seafood items, made from other vegetable substances such as konjac, are also available.
Undernourishment is a problem mainly in the central and western part of the country, while "unbalanced nutrition" is a problem in developed coastal and urban areas. Decades of food shortages and rationing ended in the 1980s. A study in 2004 showed that fat intake among urban dwellers had grown to 38.4 percent, beyond the 30 per cent limit set by the World Health Organization. Excessive consumption of fats and animal protein has made chronic diseases more prevalent. As of 2008, 22.8 percent of the population were overweight and 18.8 percent had high blood pressure. The number of diabetes cases in China is the highest in the world. In 1959, the incidence of high blood pressure was only 5.9 percent.
A typical Chinese peasant before industrialization would have eaten meat rarely and most meals would have consisted of rice accompanied with green vegetables, with protein coming from foods like peanuts. Fats and sugar were luxuries not eaten on a regular basis by most of the population. With increasing wealth, Chinese diets have become richer with more meats, fats, and sugar being consumed.
Health advocates put some of the blame on the increased popularity of Western foods, especially fast food, and other culinary products and habits. Many Western, especially American, fast food chains have appeared in China, and are highly successful economically. These include McDonald's and Kentucky Fried Chicken (KFC).
An extensive epidemiological study called the China Project is being conducted to observe the relationship of disease patterns to diet, particularly the move from the traditional Chinese diet to one which incorporates more rich Western-style foods. Controversially, Professor T. Colin Campbell has implicated the increased consumption of animal protein in particular as having a strong correlation with cancer, diabetes, heart disease, and other diseases that, while common in Western countries, were considered rare in China. He suggests that even a small increase in the consumption of animal protein can dramatically raise the risk of the aforementioned diseases.