INS and diabetic retinopathy: Height more than 2 SDS, diagnosis of T1DM before 18 years of age, no evidence of diabetic retinopathy, neuropathy of nephropathy; no intake medications, hormones, vitamins, or calcium in the preceding 6 months aside from insulin or thyroid hormones, no chronic disease, no hospitalization or DKA in the preceding months, no restriction of physical activity.