In a study of people with diabetes, cigarette smoking was found to be a risk factor for the development of retinopathy.³ In a study of people with type 1 (insulin-dependent) diabetes, those who maintained their blood sugar levels close to the normal range had less severe retinopathy, compared with those whose blood sugar levels were higher.⁴ Tighter control of blood-sugar levels can be achieved with a medically supervised program of diet, exercise, and, when appropriate, medication.