Cummings J H, Stephen A M
Gut group, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, Dundee, UK.
Eur J Clin Nutr. 2007 Dec;61 Suppl 1:S5-18. doi: 10.1038/sj.ejcn.1602936.
Dietary carbohydrates are a group of chemically defined substances with a range of physical and physiological properties and health benefits. As with other macronutrients, the primary classification of dietary carbohydrate is based on chemistry, that is character of individual monomers, degree of polymerization (DP) and type of linkage (alpha or beta), as agreed at the Food and Agriculture Organization/World Health Organization Expert Consultation in 1997. This divides carbohydrates into three main groups, sugars (DP 1-2), oligosaccharides (short-chain carbohydrates) (DP 3-9) and polysaccharides (DP> or =10). Within this classification, a number of terms are used such as mono- and disaccharides, polyols, oligosaccharides, starch, modified starch, non-starch polysaccharides, total carbohydrate, sugars, etc. While effects of carbohydrates are ultimately related to their primary chemistry, they are modified by their physical properties. These include water solubility, hydration, gel formation, crystalline state, association with other molecules such as protein, lipid and divalent cations and aggregation into complex structures in cell walls and other specialized plant tissues. A classification based on chemistry is essential for a system of measurement, predication of properties and estimation of intakes, but does not allow a simple translation into nutritional effects since each class of carbohydrate has overlapping physiological properties and effects on health. This dichotomy has led to the use of a number of terms to describe carbohydrate in foods, for example intrinsic and extrinsic sugars, prebiotic, resistant starch, dietary fibre, available and unavailable carbohydrate, complex carbohydrate, glycaemic and whole grain. This paper reviews these terms and suggests that some are more useful than others. A clearer understanding of what is meant by any particular word used to describe carbohydrate is essential to progress in translating the growing knowledge of the physiological properties of carbohydrate into public health messages.
膳食碳水化合物是一组化学性质明确的物质，具有一系列物理、生理特性及健康益处。与其他宏量营养素一样，膳食碳水化合物的主要分类基于化学性质，即单个单体的特性、聚合度（DP）和连接类型（α或β），这是1997年联合国粮食及农业组织/世界卫生组织专家磋商会所确定的。据此，碳水化合物可分为三大类：糖（DP 1 - 2）、寡糖（短链碳水化合物）（DP 3 - 9）和多糖（DP≥10）。在这一分类体系中，还使用了许多术语，如单糖和双糖、多元醇、寡糖、淀粉、变性淀粉、非淀粉多糖、总碳水化合物、糖等。虽然碳水化合物的作用最终与其基本化学性质相关，但其物理性质会对其产生影响。这些物理性质包括水溶性、水合作用、凝胶形成、结晶状态、与蛋白质、脂质和二价阳离子等其他分子的结合以及在细胞壁和其他特殊植物组织中聚合成复杂结构。基于化学性质的分类对于测量系统、性质预测和摄入量估算至关重要，但由于每类碳水化合物都具有重叠的生理特性和对健康的影响，因此无法简单地转化为营养效应。这种二分法导致了在描述食物中的碳水化合物时使用了许多术语，例如内源性糖和外源性糖、益生元、抗性淀粉、膳食纤维、可利用和不可利用碳水化合物、复合碳水化合物、血糖生成指数和全谷物。本文对这些术语进行了综述，并指出有些术语比其他术语更有用。更清楚地理解用于描述碳水化合物的任何特定词汇的含义，对于将不断增长的碳水化合物生理特性知识转化为公共卫生信息至关重要。
