RESEARCH DESIGN AND METHODS

We studied 37 consecutive type 1 diabetic patients and performed follow-up at the outpatient clinic of our diabetes unit (16 men and 21 women, aged 34±2 years [mean±SE]). Diabetes duration was 10.4±1.3 years, BMI 23.9±0.6 kg/m 2, caloric intake 2,047±71 kcal/day, fasting plasma glucose 8.76±0.40 mmol/l, C-peptide (radioimmunoassay kit; Adaltis Italia, Bologna, Italy) 0.30±0.07 ng/ml, and HbA 1c (high-performance liquid chromatography method, Variant II; BioRad, Milan, Italy) 8.1±0.24%. A total of 20 healthy subjects, matched for age, sex, BMI, and daily caloric intake, were used as control subjects (Table 1). Patients were on steady metabolic control, presented a stable body weight in the previous 6 months, did not report a history or symptoms of gastrointestinal disease, and tested negative for antibodies to gliadin and endomysium. They were on a normocaloric diet with a carbohydrate content accounting for 55–60% of calories, with restriction of simple sugars, a protein content of 1 g/kg body wt, and a lipid content of∼ 25–30% of total calories. Subjects received three premeal rapid insulin injections and one bedtime intermediate insulin injection. Two patients were macroalbuminuric (albumin excretion rate> 200 μg/min), and six were microalbuminuric (albumin excretion rate between 20 and 200 μg/min); seven subjects had background and two had preproliferative retinopathy.