Curcuminoids, the active polyphenolic compounds found in turmeric (Curcuma longa), have been investigated for their potential role in the management of diabetic retinopathy (DR), primarily due to their anti-inflammatory, antioxidant, and anti-angiogenic properties. Preclinical studies, including in vitro and animal models, have shown that curcumin can reduce oxidative stress and inhibit inflammatory cytokines involved in the pathogenesis of DR. For example, some rodent studies have demonstrated that curcumin supplementation can decrease retinal vascular leakage, inhibit VEGF expression, and reduce retinal cell apoptosis in diabetic models.

Human evidence, however, remains limited and is mostly confined to small pilot studies or adjunctive therapy trials. One small randomized controlled trial suggested that oral curcumin, when formulated for increased bioavailability, might improve visual function and reduce markers of retinal inflammation in patients with mild-to-moderate diabetic retinopathy. However, these findings have not yet been widely replicated or confirmed in large-scale, high-quality clinical trials.

In summary, while there is promising preclinical and limited clinical evidence suggesting a potential benefit of curcuminoids in the management of diabetic retinopathy, the overall strength of the evidence is still low, and more robust clinical trials are needed before curcuminoids can be recommended as a standard therapy for DR.