Abstract: Dietary fibre，also known as the seventh nutrient，is a kind of carbohydrate that cannot be digested by the human gastrointestinal tract，but can be fermented by intestinal microbiota to produce short chain fatty acids，which plays an important role in improving intestinal function and maintaining body metabolism and health. At present，there is a lack of understanding of dietary fibre in the public and the amount of intake is significantly lower than the international recommended intakes. This article reviews the definition of dietary fiber，recommended intake，and the impact on human gastrointestinal tract and health，aiming to improve the understanding of dietary fiber and its role.

Key words: dietary fibre, nutrient, short chain fatty acids, appropriate intake, gut microbiota, gastrointestinal function

摘要： 膳食纤维又被称为第七营养素，是一类不能被人体胃肠道消化的碳水化合物，但可以被肠道微生物发酵生成短链脂肪酸，对于改善肠道功能、维持机体的代谢和健康具有重要的作用。目前民众对于膳食纤维的认识普遍不足，摄入量严重低于国际推荐值。文章主要从膳食纤维的定义、推荐摄入量、对胃肠道及整体健康的影响等方面进行阐述，旨在提高对膳食纤维及其作用的认识。

关键词: 膳食纤维, 营养素, 短链脂肪酸, 适宜摄入量, 肠道微生物, 胃肠道功能