Colak Hatice, Larik Gillian N F, van Baak Marleen A, Canfora Emanuel E
Department of Nutrition and Dietetics, Faculty of Health Science, Üsküdar University, Istanbul, Turkey.
Department of Human Biology, Institute of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center+, Maastricht, the Netherlands.
Clin Nutr. 2025 Sep;52:236-251. doi: 10.1016/j.clnu.2025.08.003. Epub 2025 Aug 6.
BACKGROUND & AIMS: Increasing evidence from epidemiological studies indicates that dietary fibers are protective against the development of type 2 diabetes mellitus. Supplementation of dietary fiber may therefore be a strategy to improve metabolic health in individuals with overweight and obesity at high risk to develop type 2 diabetes mellitus (T2DM). However, results from intervention studies are inconsistent, which may be related to the form of supplementation. In this systematic review and meta-analysis, we evaluated randomized controlled trials (RCTs) investigating the effects of dietary fiber administered as single isolated fibers, mixtures of isolated fibers, or fiber-rich whole foods on markers of insulin resistance and glucose homeostasis in individuals with overweight or obesity without T2DM.
PubMed, Scopus, Web of Science and Embase databases were searched for RCTs comparing the effects of fiber supplementation with placebo treatments on glucose homeostasis. Changes in outcome parameters were analyzed using random effects meta-analyses to estimate effect size and 95 % confidence intervals (CI).
A total of 51 eligible papers (n = 3420 participants) with a study duration between one and twelve months were included in the meta-analysis. Dietary fiber supplementation improved fasting glucose concentrations -0.07 mmol/L (95 % CI: -0.12, -0.02; P = 0.0005; I = 54 %), reduced fasting insulin levels -5.89 pmol/L (95 % CI -9.18, -2.60, P = 0.0004; I = 89 %), and decreased HOMA-IR -0.38 (95 % CI: -0.68, -0.08; P < 0.00001; I = 94 %). In addition, subgroup analysis revealed that supplementation of single fibers improved fasting insulin, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), hemoglobin A1c (HbA1c) and insulin area under the curve (AUC). Isolated fiber mixtures in addition reduced fasting glucose but not insulin AUC. Supplementation of whole foods only improved HbA1c.
Dietary fiber supplementation improved glucose homeostasis and insulin sensitivity in individuals with overweight and obesity without T2DM. Although differential effects were observed based on the form of fiber supplementation, no form of fiber supplementation could be considered superior. The study was registered in PROSPERO as CRD42023427415.
越来越多的流行病学研究证据表明，膳食纤维对2型糖尿病的发生具有保护作用。因此，补充膳食纤维可能是改善超重和肥胖且有2型糖尿病（T2DM）高发病风险个体代谢健康的一种策略。然而，干预研究的结果并不一致，这可能与补充形式有关。在这项系统评价和荟萃分析中，我们评估了随机对照试验（RCT），这些试验研究了以单一分离纤维、分离纤维混合物或富含纤维的全食物形式给予膳食纤维对无T2DM的超重或肥胖个体胰岛素抵抗和葡萄糖稳态标志物的影响。
在PubMed、Scopus、Web of Science和Embase数据库中检索比较膳食纤维补充剂与安慰剂治疗对葡萄糖稳态影响的RCT。使用随机效应荟萃分析来分析结局参数的变化，以估计效应大小和95%置信区间（CI）。
共有51篇符合条件的论文（n = 3420名参与者）被纳入荟萃分析，研究持续时间为1至12个月。补充膳食纤维可使空腹血糖浓度降低0.07 mmol/L（95%CI：-0.12，-0.02；P = 0.0005；I² = 54%），空腹胰岛素水平降低5.89 pmol/L（95%CI -9.18，-2.60，P = 0.0004；I² = 89%），稳态模型评估胰岛素抵抗（HOMA-IR）降低0.38（95%CI：-0.68，-0.08；P < 0.00001；I² = 94%）。此外，亚组分析显示，补充单一纤维可改善空腹胰岛素、胰岛素抵抗稳态模型评估（HOMA-IR）、糖化血红蛋白（HbA1c）和胰岛素曲线下面积（AUC）。分离纤维混合物还可降低空腹血糖，但对胰岛素AUC无影响。补充全食物仅改善了HbA1c。
补充膳食纤维可改善无T2DM的超重和肥胖个体的葡萄糖稳态和胰岛素敏感性。尽管根据膳食纤维补充形式观察到了不同的效果，但没有一种膳食纤维补充形式可被认为是更优的。该研究已在PROSPERO注册，注册号为CRD42023427415。
