This study by an American Eye Institute determined whether a combination of vitamins B6, B9 (folate), and B12 is effective in reducing symptoms related to diabetic retinopathy, an eye disease caused by high blood glucose levels. 10 subjects with diabetic retinopathy were recruited for this six-month study. Vitamin tablets containing vitamins B6, B9, and B12 were administered twice daily, and several measurements were executed to determine (changed) signs and symptoms of the disease. Vitamin supplementation was shown to have several beneficial effects in patients with diabetic retinopathy after six months of intervention, compared with measurements before supplementation. Further details can be found in the study.
Smolek et al.