The best corrected visual activity was stable or improved in 8/8 cases.<h4>Conclusion</h4>We report a series of diabetic and hypertensive retinopathy cases with MTHFR polymorphisms and the improvement of retinal microvasculature (mainly MAs) in serial fundus photography after taking a medical food or supplement containing L-methylfolate and vitamin D. It appears that the use of nutritional supplements and medical foods containing L-methylfolate and vitamin D may be effective in facilitating the improvement of diabetic and hypertensive retinopathy. The gene discussed is MTHFR; the disease is hypertensive retinopathy.