Randomized Controlled Trial
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Aug 15, 2025; 16(8): 108166
Published online Aug 15, 2025. doi: 10.4239/wjd.v16.i8.108166
Vitamin D supplementation reduces infection rate and promotes wound healing in patients with diabetic foot ulcers
Yue-Qiao Gao, Ying-Hui Gao, Jun-Hui Xing
Yue-Qiao Gao, Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, Henan Province, China
Ying-Hui Gao, Department of Infectious Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, Henan Province, China
Jun-Hui Xing, Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, Henan Province, China
Author contributions: Gao YQ conceptualization, methodology, resources, supervision, funding acquisition, and writing review & editing; Gao YH validation, Formal analysis, writing original draft; Gao YH validation, investigation, writing review & editing. All authors have read and approved the final manuscript.
Supported by Natural Science Foundation of Henan Province, No. 202300410396; and the Young Talents Promotion Project of Henan Province, No. 2021HYTP043.
Institutional review board statement: This study was conducted in accordance with the Declaration of Helsinki. This study was approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University (2025-KY-0093-002).
Clinical trial registration statement: It was not registered at the public clinical trial registration platforms.
Informed consent statement: Written informed consent was obtained from all the participants.
Conflict-of-interest statement: The authors declare that there is no conflict of interest.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Data sharing statement: The dataset generated and analysed during the current study is available from the corresponding author upon reasonable request.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Jun-Hui Xing, MD, PhD, Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe Eastern Road, Zhengzhou 450000, Henan Province, China. xjunhui404@163.com
Received: April 7, 2025
Revised: May 20, 2025
Accepted: July 2, 2025
Published online: August 15, 2025
Processing time: 129 Days and 20.8 Hours
Abstract
BACKGROUND

Diabetic foot ulcers (DFUs) represent a common and serious complication of diabetes, characterized by impaired wound healing and an increased risk of infection. These infections severely impact patient health, necessitating extensive medical intervention, and increasing the risk of amputation. Vitamin D (VD) plays a critical role in immune regulation and tissue repair.

AIM

To investigate the effects of VD supplementation on infection rates, wound healing, and immune function in patients with DFUs.

METHODS

A randomized controlled trial was conducted involving 120 patients with DFUs. Participants were randomly assigned to either a control group (n = 60), which received standard care without VD supplementation, or an intervention group (n = 60), which received 2000 IU of oral VD3 (cholecalciferol) daily for 12 weeks. The primary outcomes included the incidence and severity of infections, whereas the secondary outcomes included wound healing rate, serum 25-hydroxyvitamin D level, levels of immune markers (cathelicidin, interleukin-6 and tumor necrosis factor-α), and adverse events, such as hypercalcemia.

RESULTS

The incidence of infection was significantly lower in the VD supplementation group (25%) compared with the control group (45%) (P = 0.01). Severe infections requiring systemic antibiotics or hospitalization were also less frequent in the VD supplementation group. Wound healing was notably enhanced in the VD supplementation group, with a 60% reduction in ulcer size compared with a 35% reduction in the control group (P < 0.01). Serum 25(OH)D level significantly increased in the VD supplementation group (from 16.5 ng/mL to 35.2 ng/mL), confirming the efficacy of VD supplementation. Immune function improved, as demonstrated by a 30% rise in cathelicidin level and a 20% decline in levels of pro-inflammatory cytokines. No adverse effects, including hypercalcemia, were reported.

CONCLUSION

The VD supplementation effectively reduced infection rate, promoted wound healing, and strengthened immune responses in patients with DFUs. These findings support the incorporation of VD as a safe and effective adjunctive therapy in the clinical management of DFUs.

Keywords: Vitamin D; Diabetic foot ulcers; Infection rate; Wound healing; Immune response; Cathelicidin; Inflammation; Randomized controlled trial

Core Tip: Diabetic foot ulcers (DFUs) are a highly prevalent and serious complication of diabetes, characterized by slow wound healing and an increased risk of infection. These infections severely impact patient health, often requiring extensive medical intervention and increasing the risk of amputation. Vitamin D plays a critical role in immune regulation and wound healing. This study found that vitamin D supplementation effectively reduced infection rates, enhanced wound healing, and strengthened immune responses in DFU cases. These findings suggest that vitamin D is a beneficial and safe adjunct to standard DFU care, potentially mitigating infection-related complications and improving clinical outcomes.