The efficacy of vitamin D supplementation for irritable bowel syndrome: a systematic review with meta-analysis

Nutrition Journal

Table 1 Characteristics of randomized controlled trials of vitamin D supplementation on IBS

Study	Country	Study design	IBS criteria	Case	Control	Vitamin D dose	Treatment duration	Primary outcomes	Secondary outcomes
Study	Country	Study design	IBS criteria	(n)	(n)	Vitamin D dose	Treatment duration	Primary outcomes	Secondary outcomes
Abbasnezhad 2016 [23]	Iran	Double-blind	IBS-C 34.1%, IBS-D 25.9%, IBS-A 40%	44	41	50000 IU VD₃ fortnightly	6 months	IBS-SSS	IBS-QoL, the measurement of GI symptoms
Khalighi Sikaroudi 2020 [24]	Iran	Double-blind	IBS-D	44	44	50000 IU VD₃ weekly	9 weeks	IBS-SSS	IL-6, CRH
El Amrousy 2018 [25]	Egypt	Double-blind	IBS-C 61.8%, IBS-D 18.6%, IBS-M 10.8%, IBS-U 8.9%	56	56	2000 IU VD₃ daily	6 months	IBS-SSS	IBS-QoL, IBS-TS
Jalili 2016 [26]	Iran	Double-blind	all subtypes (the proportion of each subtype was unclear)	25	25	50000 IU VD₃ fortnightly	6 weeks	IBS-SSS	IBS-TS

IBS irritable bowel syndrome, IBS-C, -D, -A, -M, -U IBS with predominant constipation, predominant diarrhea, predominant alternating bowel habit, mixed and unsubtyped, IBS-QoL IBS-quality of life, IBS-SSS IBS-severity scoring system, IBS-TS IBS-total score, IU international unit, VD₃ vitamin D₃

ISSN: 1475-2891