High-dose vitamin E supplementation normalizes retinal blood flow and creatinine clearance in patients with type 1 diabetes

Diabetes Care. 1999 Aug;22(8):1245-51. doi: 10.2337/diacare.22.8.1245.


Objective: To determine the effectiveness of vitamin E treatment in normalizing retinal blood flow and renal function in patients with <10 years of type 1 diabetes.

Research design and methods: An 8-month randomized double-masked placebo-controlled crossover trial evaluated 36 type 1 diabetic and 9 nondiabetic subjects. Subjects were randomly assigned to either 1,800 IU vitamin E/day or placebo for 4 months and followed, after treatment crossover, for a further 4 months. Retinal blood flow was measured using video fluorescein angiography, and renal function was assessed using normalized creatinine clearance from timed urine collections.

Results: After vitamin E treatment, serum levels of vitamin E were significantly elevated (P<0.01) in both type 1 diabetic and control patients. Hemoglobin A1c was not affected by vitamin E treatment. Diabetic patient baseline retinal blood flow (29.1+/-7.5 pixel2/s) was significantly (P = 0.030) decreased compared with that of nondiabetic subjects (35.2+/-7.2 pixel2/s). After vitamin E treatment, diabetic patient retinal blood flow (34.5+/-7.8 pixel2/s) was significantly increased (P<0.001) and was comparable with that of nondiabetic subjects. Additionally, vitamin E treatment significantly (P = 0.039) normalized elevated baseline creatinine clearance in diabetic patients.

Conclusions: Oral vitamin E treatment appears to be effective in normalizing retinal hemodynamic abnormalities and improving renal function in type 1 diabetic patients of short disease duration without inducing a significant change in glycemic control. This suggests that vitamin E supplementation may provide an additional benefit in reducing the risks for developing diabetic retinopathy or nephropathy.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Analysis of Variance
  • Creatinine / metabolism*
  • Cross-Over Studies
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetic Retinopathy / drug therapy
  • Diabetic Retinopathy / metabolism
  • Dietary Supplements*
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Metabolic Clearance Rate
  • Middle Aged
  • Plasminogen Activator Inhibitor 1 / blood
  • Regional Blood Flow / drug effects
  • Retinal Vessels / drug effects*
  • Treatment Outcome
  • Vitamin E / adverse effects
  • Vitamin E / therapeutic use*


  • Plasminogen Activator Inhibitor 1
  • Vitamin E
  • Creatinine