Diabetic Retinopathy

Diabetic retinopathy is an eye disorder that affects the retina, the "projection screen" on which light that passes through the lens of the eye is thrown. In diabetic retinopathy, the capillaries that nourish the retina leak fluid or blood. This leakage results in inadequate circulation to the cells that respond to light and relay visual impulses to the optic nerve, which carries these impulses to the brain. Diabetic retinopathy is a common cause of blindness in people with severe diabetes. There usually are no symptoms until the individual begins losing vision.

The risk factors for diabetic retinopathy include age, the length of time the individual has had diabetes, and the presence of a "sticky" protein in the blood called glycosylated hemoglobin. Another risk factor for diabetic retinopathy is the presence of insulin like growth factor, a hormone produced in excess during diabetes. This hormone encourages the growth of fragile capillaries in the eye that easily break and leak fluid. Conventional treatment consists of laser surgery, which seals the leaking blood vessels.

Herbal treatments for diabetic retinopathy are primarily preventative. Herbs that provide large quantities of bioflavonoids strengthen the capillaries and slow the progress of or prevent retinopathy even when blood sugars are poorly controlled. The best preventative for diabetic retinopathy, however, is careful control of blood sugars and regular eye exams to catch problems early.

Supplements and herbs

• Bilberry Tablets. Take 240-360 mg daily.
  Helps prevent clotting in blood vessels serving the retina.
• Chanca piedra Tincture. Take 1 dropperful in 1/2 cup water twice daily.
  Stops the formation of compounds that damage the retina.
• Ginkgo Ginkgolide tablets. Take 160-180 mg once daily.
  Prevents damage in retina cells responsible for distinguishing colors.
• Hawthorn Tablets. Take 100-250 mg 3 times daily.
  Helps strengthen blood vessels supplying the eye's surface. Reduces blood-vessel response to emotional tension.
• Jambul Seeds. Use 2 tsp-1 tbsp (3-5 gm) in cooking daily.
  Lowers blood sugars. Retards blood-vessel inflammation.
• Oligomeric proanthocyanidins (OPCs) Grape seed or pine-bark extract tablets. Take 200 mg daily.
  Antioxidant. Reduces blood-vessel inflammation.
• Quercetin Tablets. Take 125-250 mg 3 times daily, between meals.
  Slows formation of insulin like growth factor. Prevents blood clots.
• Soy isoflavone concentrate. Tablets. Take about 3,000 mg once daily.
  Slows formation of insulin-like growth factor.

What else you can do

• Eat blackberries, blueberries, and cherries to the extent that they are allowed in your diet. These fruits contain proanthocyanidins similar to those in hawthorn, and help strengthen the tiny blood vessels serving the retina.
• Take 1,000 milligrams of glutamine daily. Glutamine may slow or prevent damage to the retina, even after damage to the blood vessels serving it, by preventing free radical damage. However, do not take glutamine supplements if you have cirrhosis of the liver or kidney problems, or if you have had Reye's syndrome. Raw spinach and parsley also are good sources of glutamine.
• Don't skip insulin shots to try to lose weight. There are numerous reports in the medical literature, especially among teenagers and adult women, of people who developed diabetic retinopathy after reducing insulin dosage or skipping injections altogether as a form of weight control.
• Avoid vitamin C supplements. Increasing doses of vitamin C worsens diabetic retinopathy, especially for people with diabetes who do not take insulin.
• Make sure to have an annual eye exam to detect the onset of retinopathy. Laser surgery can help stem vision loss, but each laser weld produces a permanent blind spot even if the procedure is successful. Sometimes surgery is necessary, but prevention is a superior approach.
• Tight control is a program of keeping fasting blood sugar levels in the 125 to 135 milligrams per deciliter (mg/ dl) range and post-prandial (after-meal) sugars to about 165 mg/ dl. Tight control is confirmed by a blood test , for HbA1C, or the percentage of "sticky" red blood cells. A reading below 6.5 percent confirms tight control. This program, now recommended for all people with diabetes, reduces the risk of retinopathy by about 60 percent.
• Tight control is one part of a larger overall program known as intensive therapy. This approach uses, in addition to tight control, a combination of diet, exercise, and medication to control high blood pressure. In a study of 166 people with diabetes, intensive therapy reduced the incidence of retinopathy by another 55 percent, in addition to producing even more dramatically lowered rates of nerve damage and kidney disease. The cost of tight control, however, is weight gain. Despite eating the same number of calories as people in a control group, and eating less fat, those on intensive therapy for two years gained an average of 9 pounds (4 kilograms) more than their counterparts in the control group. However, this effect can be offset through use of the herb wild angelica.
• Although not a substitute for other treatments, including surgery, acupuncture tan restore normal circulation to the eye and slow or halt the progression of diabetic retinopathy. It can also lower eye pressures caused by glaucoma, which can accompany retinopathy.
• Researchers at the National Eye Institute induced a condition resembling diabetic retinopathy in dogs and then treated the animals with an experimental medication called sorbinil, which suppresses the action of an enzyme that converts excess sugar in the blood into an alcohol that seems to damage the retinal blood vessels. In this study, the sorbinil treatment blocked the progression of retinopathy.