Intermittent fasting and the liver: Focus on the Ramadan model

Table 1 Studies focusing on Ramadan fasting and non-alcoholic fatty liver disease

	Aliasghari et al[42], 2017	Ebrahimi et al[53], 2018	Gad et al[56], 2022	Arabi et al[58], 2015	Rahimi et al[59], 2017	Mari et al[63], 2021
Type of study	Prospective observational	Prospective observational	Prospective observational	Prospective observational without a control group	Prospective observational without a control group	Retrospective, case-control study
Number of patients	83	83	40	50	60	155
Anthropometric measures	Improved in fasted NAFLD patients	Improved in fasted NAFLD patients	Improved (no control group)	Non-significant improvement with fasting	Non-significant change	Improved in fasted NAFLD/NASH patients
Hormones and biomarkers evaluated	Plasma insulin, and insulin resistance, reactive protein, and interleukin 6 improved in the fasting group	Vaspin and omentin-1 were reduced in the fasting group	-	-	-	HOMA-IR, CRP improved
Liver biochemical profile		-	Improved	Improved	ALT mean level increased with fasting
Lipid profile		-	Improved	Improved	-
Sugar profile	Improved	-	Improved	FBS increased after Ramadan	-
Imaging profile		-	US calculated liver stiffness and controlled attenuation parameters improved	US used only in the diagnosis of fatty liver	-	-
Others		-	Fibrosis score FIB-4 score improved	Blood pressure significantly improved	-	NFS, BARD scores, and FIB4 scores improved

NAFLD: Non-alcoholic fatty liver disease; FBS: Fasting blood sugar; ALT: Alanine aminotransferase; HOMA-IR: Homeostatic model assessment of β-cell function and insulin resistance; CRP: C-reactive protein; NASH: Steatohepatitis; NFS: Non-alcoholic fatty liver disease fibrosis score; FIB4: Fibrosis-4; BARD scores: The BARD score is composed of only three variables: Aspartate aminotransferase/alanine aminotransferase ratio, presence of diabetes and body mass index; US: Ultrasound.

Table 2 Publications focusing on liver cirrhosis and Ramadan fasting

Ref.	Type of publication	Patients assessed	Findings
Elnadry et al[17], 2011	Observational and comparative	Chronic hepatitis and cirrhotics (child A and B), n = 202; Fasting group, 103 patients, 57 chronic hepatitis and 46 cirrhotics. Non-fasting group included 99 patients, 52 with chronic hepatitis, and 47 cirrhotics	Dyspeptic symptoms were higher in the fasting group. GI bleeding during Ramadan was higher in the fasting group compared to the non-fasting, but variceal bleeding was significantly higher in the non-fasting group. The chronic hepatitis fasting group showed non-significant changes pre-, during, and post-Ramadan regarding liver functions. Fasting cirrhotic group patients: The frequency of deterioration to Child class C was high
Elfert et al[64], 2011	Observational and non-comparison	Cirrhotics (Child A, B, and C), n = 216	Twenty-seven patients discontinued their fast due to fatigue. Variceal bleeding and encephalopathy were reported in 8 and 6 patients, respectively. Ramadan fasting had no significant effect on PV diameter or portal blood flow. Male sex, Child class A, and absence of GI bleeding were independent factors in the reduction of liver enzymes and serum glucose during Ramadan fasting. Older age, DM, and Child class C were independent factors in the elevation of serum bilirubin and creatinine during Ramadan fasting
Mohamed et al[65], 2016	Observational and non-comparison	Cirrhotics (Child A, B, and C), n = 40	Cirrhotic patients showed significant short-term changes in the portal blood flow (increases CI). Seven patients developed complications including 2 cases of variceal bleeding. Due to deteriorations reported in liver functions Child class C patients should not fast
Mohamed et al[66], 2018	Observational and comparative	Cirrhotic (Child A and B) and healthy volunteers; n = 72; comprised cirrhotic fasting (n = 34), cirrhotic non-fasting (n = 8) and healthy volunteers (n = 30)	Patients with cirrhosis showed changes in their portal hemodynamics with increased CI. MELD score and serum albumin showed significant changes in comparison to healthy subjects
Emara et al[15], 2021	Review and practice recommendations	Cirrhotic patients. Analysis of the evidence for the above-mentioned studies	Cirrhotic patients Child A can observe RF especially if following NAFLD guidelines provided that certain evaluations are done in advance together with close observation during Ramadan. Cirrhotic patients Child B and C should not fast. The risk of decompensation is high
Al-Jafar et al[55], 2023	Systematic review and meta-analysis	Healthy individuals and patients with different comorbidities including cirrhosis and NAFLD. Analysis of many studies	RF was associated with reductions in anthropometric measures in all patients including cirrhotics. These changes start to appear in the second week of Ramadan and diminish 3 weeks after Ramadan

NAFLD: Non-alcoholic fatty liver disease; RF: Ramadan fasting; GI: Gastrointestinal; CI: Congestive index; DM: Diabetes mellitus; PV: Portal vein; MELD: Model for end-stage liver disease.