Light exposure and type 2 diabetes mellitus: a bibliometric analysis of research hotspots and emerging frontiers from...

Type 2 diabetes mellitus is characterized by insulin resistance, impaired β-cell function, and persistent hyperglycemia. Light exposure may further influence glucose metabolism by modulating vitamin D synthesis, circadian rhythms, melatonin secretion, and sleep-related behaviors.

Relevant publications indexed in the Web of Science Core Collection from 2001 to 2025 were retrieved. A total of 2491 studies were finally included, and bibliometric and visualization analyses were performed using Bibliometrix, VOSviewer, and CiteSpace.

The number of publications in this field showed a sustained increase, with a marked acceleration after 2019 and a peak in 2024. The United States and China were the main contributing countries. High-frequency keywords included type 2 diabetes, insulin resistance, obesity, inflammation, glycemic control, circadian rhythm, sleep, and gut microbiota. Research hotspots have shifted from early topics related to vitamin D, obesity, and glucose metabolism toward light exposure, circadian rhythm disruption, sleep behavior, and environmental chronomedicine.

Research on light exposure and type 2 diabetes has expanded from the "sunlight-vitamin D-glucose metabolism" framework to circadian and behavioral medicine. Future studies should integrate objective light exposure assessment, sleep/activity monitoring, and continuous glucose monitoring data to further verify the underlying mechanisms.