ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium; Division of Endocrinology, Erasmus Hospital, Université Libre de Bruxelles, Brussels, Belgium.
ULB Center for Diabetes Research, Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium; Radiotherapy Department, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium.
Am J Clin Nutr. 2023 Oct;118(4):739-753. doi: 10.1016/j.ajcnut.2023.07.018. Epub 2023 Jul 25.
The impact of the dietary fat type on type 2 diabetes (T2D) remains unclear.
We aimed to evaluate the effects of replacing dietary saturated fatty acids (SFA) with mono- or poly-unsaturated fatty acids (MUFA and PUFA, respectively) on insulin sensitivity, pancreatic β-cell function, and glucose tolerance, as surrogate endpoints for T2D.
We conducted a systematic review and meta-analysis of randomized controlled trials that replaced ≥5% of total energy intake provided by SFA with MUFA or PUFA and reported indexes of insulin sensitivity, β-cell function, and/or glucose tolerance. We searched MEDLINE, Scopus, and the Cochrane Library (CENTRAL) up to 9 January, 2023. Eligible interventions had to be isocaloric, with no significant difference in other macronutrients. Data were synthesized using random-effects model meta-analysis.
Of 6355 records identified, 10 parallel and 20 crossover trials with 1586 participants were included. The mean age of the participants was 42 years, 47% were male, mean body mass index (BMI; in kg/m) was 26.8, median baseline fasting glucose was 5.13 mmol/L, and the median duration of interventions was 5 weeks. Replacing SFA with MUFA or PUFA had no significant effects on insulin sensitivity [standardized mean difference (SMD) SFA compared with MUFA: 0.01, 95% confidence interval (CI): -0.06 to 0.09, I = 0% and SMD SFA compared with PUFA: 0, 95% CI: -0.15 to 0.14, I = 0%]. Replacing SFA with MUFA did not significantly impact the β-cell function, evaluated by the disposition index (mean difference: -12, 95% CI: -158 to 133, I=0%). Evidence on glucose tolerance (SFA compared with MUFA or PUFA) and on β-cell function when SFA were replaced with PUFA was scant.
Short-term substitution of saturated with unsaturated fat does not significantly affect insulin sensitivity nor β-cell function (the latter in the SFA compared with MUFA comparison). Future studies are needed to elucidate longer term effects of dietary fat saturation on glucose homeostasis. This trial was registered at PROSPERO as CRD42020178382.
膳食脂肪类型对 2 型糖尿病（T2D）的影响仍不清楚。
我们旨在评估用单不饱和或多不饱和脂肪酸（MUFA 和 PUFA，分别）替代膳食饱和脂肪酸（SFA）对胰岛素敏感性、胰岛β细胞功能和葡萄糖耐量的影响，这些是 T2D 的替代终点。
我们对随机对照试验进行了系统评价和荟萃分析，这些试验用 MUFA 或 PUFA 替代了总能量摄入的≥5%，并报告了胰岛素敏感性、β细胞功能和/或葡萄糖耐量的指标。我们检索了 MEDLINE、Scopus 和 Cochrane 图书馆（CENTRAL），截至 2023 年 1 月 9 日。符合条件的干预措施必须是等热量的，其他宏量营养素没有显著差异。使用随机效应模型荟萃分析合成数据。
在 6355 条记录中，有 10 项平行试验和 20 项交叉试验纳入了 1586 名参与者。参与者的平均年龄为 42 岁，47%为男性，平均体重指数（BMI；kg/m）为 26.8，中位基线空腹血糖为 5.13mmol/L，干预的中位持续时间为 5 周。用 MUFA 或 PUFA 替代 SFA 对胰岛素敏感性没有显著影响[与 SFA 相比 MUFA 的标准化均数差（SMD）：0.01，95%置信区间（CI）：-0.06 至 0.09，I=0%和 SFA 与 PUFA 的 SMD：0，95%CI：-0.15 至 0.14，I=0%]。用 MUFA 替代 SFA 对胰岛β细胞功能（通过胰岛β细胞功能指数评估）没有显著影响，差值为-12，95%CI：-158 至 133，I=0%。关于葡萄糖耐量（SFA 与 MUFA 或 PUFA 相比）和 SFA 用 PUFA 替代时的胰岛β细胞功能的证据很少。
短期用不饱和脂肪替代饱和脂肪不会显著影响胰岛素敏感性或胰岛β细胞功能（在 SFA 与 MUFA 比较中为后者）。需要进一步的研究来阐明膳食脂肪饱和度对葡萄糖稳态的长期影响。本试验在 PROSPERO 注册为 CRD42020178382。
