Dtsch Arztebl Int. 2021 Feb 5;118(5):71-78. doi: 10.3238/arztebl.m2021.0010.
The excessive consumption of free sugars, including fructose, is considered a cause of overweight and metabolic syndrome throughout the Western world. In Germany, the prevalence of overweight and obesity among adults (54%, 18%) and children (15%, 6%) has risen in the past few decades and has now become stable at a high level. The causative role of fructose is unclear.
This review is based on publications retrieved by a selective search in PubMed and the Cochrane Library, with special attention to international guidelines and expert recommendations.
The hepatic metabolism of fructose is insulin-independent; because of the lack of a feedback mechanism, it leads to substrate accumulation, with de novo lipogenesis and gluconeogenesis. Recent meta-analyses with observation periods of one to ten weeks have shown that the consumption of fructose in large amounts leads to weight gain (+ 0.5 kg [0.26; 0.79]), elevated triglyceride levels (+ 0.3 mmol/L [0.11; 0.41]), and steatosis hepatis (intrahepatocellular fat content: + 54% [29; 79%]) when it is associated with a positive energy balance (fructose dose + 25-40% of the total caloric requirement). Meta-analyses in the isocaloric setting have not shown any comparable effects. Children, with their preference for sweet foods and drinks, are prone to excessive sugar consumption. Toddlers under age two are especially vulnerable.
The effects that have been observed with the consumption of large amounts of fructose cannot be reliably distinguished from the effects of a generally excessive caloric intake. Further randomized and controlled intervention trials of high quality are needed in order to determine the metabolic effects of fructose consumed under isocaloric conditions. To lessen individual consumption of sugar, sugary dietary items such as sweetened soft drinks, fruit juice, and smoothies should be avoided in favor of water as a beverage and fresh fruit.
在整个西方世界，过量摄入游离糖（包括果糖）被认为是导致超重和代谢综合征的一个原因。在德国，成年人（54%，18%）和儿童（15%，6%）超重和肥胖的比例在过去几十年中有所上升，目前已稳定在较高水平。果糖的致病作用尚不清楚。
本综述基于在 PubMed 和 Cochrane 图书馆进行选择性检索获得的出版物，特别关注国际指南和专家建议。
果糖在肝脏中的代谢不受胰岛素调控；由于缺乏反馈机制，果糖会导致底物堆积，进而促进肝内脂肪生成和糖异生。最近为期一至十周的meta 分析显示，大量摄入果糖会导致体重增加（+0.5 公斤[0.26；0.79]）、甘油三酯水平升高（+0.3mmol/L[0.11；0.41]）和肝脂肪变性（肝细胞内脂肪含量增加：+54%[29；79%]），当与正能 量平衡（果糖剂量+25-40%总热量需求）相关联时。等热量条件下的 meta 分析并未显示出任何可比的效果。儿童偏爱甜食和饮料，容易摄入过多的糖分。两岁以下的幼儿尤其容易受到影响。
大量摄入果糖所观察到的影响与普遍过度摄入热量的影响难以区分开来。需要进一步开展高质量的随机对照干预试验，以确定在等热量条件下摄入果糖的代谢影响。为了减少个人对糖的摄入，应避免饮用含糖软饮料、果汁和冰沙等含糖饮食，以水和新鲜水果作为饮品。
