The impact of Ramadan fasting on the metabolic syndrome severity in relation to ethnicity and sex: Results of a systematic review and meta-analysis

Abstract

Aims: The primary goal of this meta-analysis was to examine the changes in various components of metabolic syndrome (MetS) in healthy adults who observed Ramadan fasting (RF) before Ramadan (T1) and at the end of RF (T2). A secondary goal was to assess the impact of RF on MetS severity in various ethnic and sex groups using the MetS z-score.

Data synthesis: Using PRISMA2020, seven databases were searched for relevant studies published between January 1950 and March 2022. Data extraction involved high-density lipoprotein cholesterol (HDL), triglycerides (TG), fasting blood glucose (FBG), waist circumference (WC), systolic blood pressure (SBP), and diastolic blood pressure (DBP) for T1 and T2, respectively. The MetS z-score was computed according to international diabetes federation criteria. At T1, the pooled estimates of HDL, TG, FBG, WC, SBP, DBP, and MAP were 1.20 [1.13; 1.27] mmol/L, 1.32 [1.23; 1.42] mmol/L, 4.98 [4.82; 5.15] mmol/L, 87.21 [84.21; 90.21] Cm, 114.22 [101.45; 126.99] mmHg, 76.80 [70.12; 83.47] mmHg, and 89.27 [80.56; 97.98] mmHg, respectively. At T2, the pooled estimates of HDL, TG, FBG, WC, SBP, DBP, and MAP were 1.24 [1.18; 1.31] mmol/L, 1.24 [1.14; 1.34] mmol/L, 4.77 [4.55; 4.99] mmol/L, 85.73 [82.83; 88.64] Cm, 109.48 [97.20; 121.75] mmHg, 74.43 [68.01; 80.85] mmHg, and 86.11 [77.74; 94.48] mmHg, respectively. The MetS z-score showed improvement at T2 for all ethnic groups and both sexes by -0.22 [-0.24; -0.01].

Conclusions: The current meta-analysis suggests that the RF positively impact the MetS components and the overall MetS z-score.

Prospero registration number: ID CRD42022329297 OPEN SCIENCE FRAMEWORK IDENTIFIER: DOI 10.17605/OSF.IO/U9H7T.

Keywords: Cardiometabolic syndrome; Insulin resistance syndrome X; Intermittent fasting (IF); Metabolism; Reaven syndrome X; Time-restricted eating (TRE).