Dietary fiber refers to the general term for carbohydrate polymers containing three or more degrees of polymerization, which are generally classified according to different dietary sources and can be divided into three categories.
The main sources of dietary fiber are natural plant foods, such as vegetables, fruits, whole grains, potatoes and legumes, etc. Animal foods do not contain dietary fiber. Before 1987, whether dietary fiber belonged to the category of nutrients has been controversial, water and dietary fiber were not counted as nutrients in the 60s, and dietary fiber was not counted as nutrients in the 70s. Prior to this (1900), dietary fiber was counted as a nutrient, and the International Health Organization (WTO) declared it the seventh largest nutrient in the late 1980s with the Japanese Ministry of Foreign Affairs announcing the world's first dietary fiber health food.
According to mainland regulations, dietary fiber refers to a carbohydrate polymer containing 3 or more degrees of polymerization, although dietary fiber can not be decomposed by the human body's small intestine, but it is beneficial to human health. At present, there are about a thousand kinds of dietary fiber in nature, which can be divided into different types according to different bases.
But usually the continent is divided according to dietary sources, which can be divided into three categories: the first is the part that naturally exists in the plant body, which is a complete carbohydrate polymer; the second is the polymer of carbohydrates extracted from plants by physical, chemical or enzymatic methods; and the third type refers to the synthetic carbohydrate polymers.
As an important part of food, dietary fiber has an important physiological role. Dietary fiber can promote chewing, increase the secretion of saliva, combine a large amount of water to make the stomach expand, increase viscosity after hydration, can delay the absorption of nutrients and the emptying of the stomach, has an ileal brake effect, thereby slowing down the peristalsis of the intestine. Through these effects, dietary fiber can promote the body to produce satiety, on the other hand, dietary fiber can regulate the gastrointestinal secretion of hormones related to satiety, such as insulin, ghrelin, glucagon-like, gallbladdertokinin, etc. [1].
Generally speaking, natural dietary fiber is mainly derived from cereals, vegetables and fruits, beans, potatoes, etc., in cereals and legumes and vegetables and fruits, dietary fiber is usually present in the epidermis of food, dietary fiber is helpful for laxative, promote digestion, so the human body can not lack dietary fiber intake.
This issue is written by Liao Yuying and Zhao Lichao
Editor: Peng Mingqian
bibliography:
[1] Shang Longchen[1,2,3] Li Jing[1,2,3] Li Bin[1,2,3] . Research Progress on Dietary Fiber Satiety[J]. Journal of Food Safety and Quality Inspection, 2018.
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