Dietary factors and diabetic retinopathy: An umbrella review of systematic reviews and meta-analyses

Shuyuan Shi; Qingxin Zhou; Shuyan Zhang; Tianchi Song; Yisha Zuhaer; Hongyu Sun; Siyan Zhan; Feng Sun

doi:10.59717/j.xinn-nutri.2026.100024

The Innovation Nutrition > 2026 Vol. 1 > No. 2 > 100024

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Dietary factors and diabetic retinopathy: An umbrella review of systematic reviews and meta-analyses

1.
China Rehabilitation Science Institute, Department of Disability Prevention Research, Beijing 100068, China
2.
Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing 100191, China
3.
Tianjin Centers for Disease Control and Prevention, Tianjin 300011, China
4.
School of Public Health, Shihezi University, Xinjiang Uygur Autonomous Region, Shihezi 832000, China
5.
Key Laboratory of Epidemiology of Major Diseases (Peking University), Ministry of Education, Beijing 100191, China
6.
Department of Nursing Humanities Teaching and Research, School of Nursing, Peking University, Beijing 100191, China
7.
Center of Postmarketing Safety Evaluation, Peking University Health Science Center, Beijing 100191, China
8.
Center for Intelligent Public Health, Institute for Artificial Intelligence, Peking University, Beijing 100191, China
9.
Department of Ophthalmology, Peking University Third Hospital, Beijing 100191, China
10.
School of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi 830017, China

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Corresponding authors: sunfeng@bjmu.edu.cn (F.S.); 1811210176@pku.edu.cn (S.S.)
Received Date: June 12, 2026

Accepted Date: July 14, 2026

Published Online: July 19, 2026

The Innovation Nutrition 1(2), https://doi.org/10.59717/j.xinn-nutri.2026.100024 | Cite this article

GRAPHICAL ABSTRACT

GRAPHICAL ABSTRACT

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. Low vitamin D levels were convincingly linked to a higher risk of diabetic retinopathy (DR).
  
  Omega-3 fatty acid intake and higher serum vitamin B12 showed highly suggestive evidence for lowering DR risk.
  
  Mediterranean diet, vitamins C and E consistently linked to lower DR risk, but weak evidence.
  
  Most systematic reviews had very low methodological quality, so findings should be interpreted cautiously.
  
  Current clinical guidelines lack DR-specific dietary advice, highlighting a gap between evidence and practice.

ABSTRACT

ABSTRACT

Diabetic retinopathy (DR) is a leading cause of vision impairment globally. Numerous systematic reviews and meta-analyses (SRMAs) have investigated specific dietary components, but a comprehensive synthesis is lacking. This umbrella review aims to summarize and evaluate the evidence from SRMAs on associations between dietary factors and DR risk. PubMed, Scopus, Web of Science, and the Cochrane Library were searched from inception to May 1, 2026. SRMAs of observational studies or randomized controlled trials examining any dietary factors and DR incidence or prevalence in individuals with diabetes were included. Of 2162 articles screened, 18 were included. The most consistent finding was the protective association between Mediterranean diet and DR. Low serum vitamin D demonstrated convincing evidence for DR risk, while highly suggestive evidence was identified for omega-3 fatty acid intake and serum vitamin B12. Multiple qualitative systematic reviews consistently concluded that higher serum vitamin C and E, vitamin D intake, plasma monounsaturated fatty acids, and tea intake were associated with lower DR risk. Although conclusions on other dietary factors were inconsistent, most studies showed protective effects of fish, fruits, vegetables, and dietary fiber. However, most included SRMAs were rated as very low methodological quality, indicating that even statistically robust associations should be interpreted cautiously and that rigorous prospective studies and targeted interventions are still needed.

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Shi S., Zhou Q., Zhang S., et al. (2026). Dietary factors and diabetic retinopathy: An umbrella review of systematic reviews and meta-analyses. The Innovation Nutrition 1:100024. https://doi.org/10.59717/j.xinn-nutri.2026.100024

Shi S., Zhou Q., Zhang S., et al. (2026). Dietary factors and diabetic retinopathy: An umbrella review of systematic reviews and meta-analyses. The Innovation Nutrition 1:100024. https://doi.org/10.59717/j.xinn-nutri.2026.100024

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Dietary factors and diabetic retinopathy: An umbrella review of systematic reviews and meta-analyses

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