Evidence map›Paper›PMID 42226190›Full record

ArticleBMC public health2026

Nonlinear association between composite dietary antioxidant index and irritable bowel syndrome: insights from UK Biobank.

Laifu Li, Yan Zhuang, Yan Ran, Lianli Wang, Jiamiao Chen, Lin Mei, Fangchen Ye, Yating Sun, Zhuoya Sun, Shiwei Lu and 2 more

Abstract read
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Article in BMC public health, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

12 authors.

Laifu Li *Department of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Yan Zhuang *Department of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Yan RanDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Lianli WangDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Jiamiao ChenDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Lin MeiDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Fangchen YeDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Yating SunDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Zhuoya SunDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Shiwei LuDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Yu NingDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Fei DaiDepartment of Gastroenterology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China. daifei68@xjtu.edu.cn.

Funding

Key Research and Development Projects of Shaanxi Province S2023-YF-YBSF-1670
6 · The paper itself

Abstract

backgroundThe relationship between overall dietary antioxidant potential and risk of irritable bowel syndrome (IBS) is unclear and needs further epidemiologic evidence.

methodsIn this study, we included a total of 157,900 participants from the UK Biobank without irritable bowel syndrome at baseline between 2006 and 2010. Dietary intake was assessed using the online 24-hour dietary recall questionnaire, Oxford WebQ. IBS was identified using the ICD-10 code (K58). The composite dietary antioxidant index (CDAI) was the sum of Z scores for mean intake of individual vitamins A, C, E, manganese, selenium, and zinc from five 24-hour dietary recalls.

resultsDuring a mean follow-up time of 13.41 years, 2,007 incident cases of IBS were identified among the 157,900 participants. Restricted cubic spline (RCS) showed a nonlinear association (p for nonlinear < 0.001) between CDAI and the risk of IBS, and two-piecewise linear regression identified an inflection point at -0.9. Segmented Cox regression demonstrated that increasing CDAI significantly reduced the risk of IBS when CDAI < -0.9 (HR: 0.900, 95% CI: 0.820-0.988, P = 0.027); however, when CDAI ≥ -0.9, there was a 3% increased risk of IBS (HR: 1.030, 95% CI: 1.001-1.060, P = 0.046). Furthermore, compared to participants in Quintile 2 of CDAI, individuals in Quintile 1 had a 23% increased risk of IBS (HR: 1.228, 95% CI: 1.071-1.408, P = 0.003), while no significant differences were observed for participants in the other quintiles. Nonlinear analysis of independent dietary nutrients suggested a significant U-shaped association only between vitamin C and the risk of IBS, with an inflection point at Z score = -0.1. Sensitivity analyses with multiple imputation for missing covariates supported a negative association between antioxidant intake and IBS risk before the inflection point of CDAI. In contrast, after the inflection point, CDAI seemed to be unrelated to IBS risk.

conclusionModerate supplementation of antioxidants, particularly vitamin C, is beneficial in reducing the risk of IBS. However, excessive intake of dietary antioxidants tends to have no protective effect on IBS risk.

Indexed as

AntioxidantsDietIrritable Bowel SyndromeAdultAgedBiological Specimen BanksFemaleHumansMaleMiddle AgedNonlinear DynamicsRisk FactorsUK BiobankUnited KingdomAntioxidantsComposite dietary antioxidant indexIrritable bowel syndromeUK BiobankVitamin C

Identifiers

PMID42226190
PMCPMC13435507

What Socratic holds

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LicenceCC BY-NC-ND
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.