Flavonoids, a diverse group of phytonutrients found in fruits, vegetables, and certain medicinal plants, have shown promise in the management of diabetic retinopathy (DR) based on scientific evidence. Multiple experimental and clinical studies suggest that flavonoids possess antioxidant, anti-inflammatory, and vasoprotective properties, all of which are relevant to the pathophysiology of DR. The rationale for their use centers on their ability to reduce oxidative stress and inflammation in retinal tissues, inhibit vascular endothelial growth factor (VEGF) expression, and stabilize capillary walls—mechanisms implicated in the progression of DR.

Specific flavonoids like quercetin, rutin, and anthocyanins have been studied in both animal models and small human trials. For example, some studies show that supplementation with these compounds may help decrease retinal vascular leakage, reduce microaneurysm formation, and improve retinal blood flow. However, while preclinical data are robust, clinical evidence remains limited and often involves small sample sizes or short intervention periods. Systematic reviews (e.g., PMID: 28697479) conclude that flavonoid supplementation may offer adjunctive benefit, but high-quality, large-scale randomized controlled trials are still needed to clearly define their efficacy and safety for DR in humans.

In summary, the use of flavonoid mixtures for diabetic retinopathy is supported by a moderate level of scientific evidence, mainly from preclinical research and preliminary clinical studies.