Obesity mediates the association of outdoor artificial light at night with type 2 diabetes mellitus

Xiaotian Liu; Zhongao Ding; Yinghao Yuchi; Ruiying Li; Wei Liao; Xiaokang Dong; Wenqian Huo; Jian Hou; Hualiang Lin; Xin Liu; Kai Zhang; Chongjian Wang

doi:10.1016/j.isci.2026.115036

Obesity mediates the association of outdoor artificial light at night with type 2 diabetes mellitus

iScience. 2026 Feb 26;29(3):115036. doi: 10.1016/j.isci.2026.115036. eCollection 2026 Mar 20.

Authors

Xiaotian Liu¹, Zhongao Ding¹, Yinghao Yuchi¹, Ruiying Li¹, Wei Liao¹, Xiaokang Dong², Wenqian Huo¹, Jian Hou¹, Hualiang Lin³, Xin Liu⁴, Kai Zhang⁵, Chongjian Wang^{1

2}

Affiliations

¹ Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, Henan, P.R. China.
² NHC Key Laboratory of Prevention and Treatment of Cerebrovascular Diseases, Zhengzhou, Henan, P.R. China.
³ Department of Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong, P.R. China.
⁴ School of Public Health and Emergency Management, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China.
⁵ Department of Environmental Health Sciences, College of Integrated Health Sciences, University at Albany, Rensselaer, NY, USA.

Abstract

This study aims to explore the association of outdoor ALAN exposure with T2DM and the mediating effects of obesity in Chinese rural adults. A total of 38,108 participants were recruited from the Henan Rural Cohort. ALAN was positively associated with T2DM and FPG, and negatively associated with insulin, HOMA-IR, as well as HOMA-β, and the effect sizes of per-quartile increase in ALAN were 1.24(1.19, 1.28), 0.14(0.13, 0.16), -1.19(-1.24, -1.14), -0.22(-0.25, -0.20), and -27.30(-29.11, -25.48), respectively. The elderly, men, current smokers, individuals with lower education or income, or physical inactivity were more vulnerable to ALAN-related adverse health effects. The associations of ALAN with T2DM and glucose metabolism were mediated by WC, BMI, WHtR, WHR, VFI, and BFP, with estimated mediation proportions of 36.41%, 25.14%, 33.98%, 22.33%, 24.39%, and 25.85%, respectively, for T2DM. These findings emphasize the need for targeted public health interventions for reducing ALAN-related adverse health effects in rural areas.

Keywords: Health sciences.