Influence of breastfeeding on obesity and type 2 diabetes risk factors in Latino youth with a family history of type 2 diabetes.

OBJECTIVE To determine whether breastfeeding is related to total adiposity, regional adiposity, and glucose and insulin dynamics in overweight Latino youth throughout puberty. RESEARCH DESIGN AND METHODS The relation between breastfeeding and diabetes risk was determined in 240 overweight (BMI > or =85th percentile) Latino children (aged 8-13 years) with a positive family history of type 2 diabetes. Children were examined at baseline (Tanner pubertal stage 1) and for 2 more years as they advanced in pubertal maturation. Children were divided into the following categories: never breastfed (n = 102), breastfed 0-5.99 months (n = 61), breastfed 6-11.99 months (n = 24), and breastfed > or =12 months (n = 53). Tanner pubertal stage was determined by physical examination. Visceral and subcutaneous abdominal fat were determined by magnetic resonance imagining, and total body fat, total lean tissue mass, and percent body fat were measured by dual-energy X-ray absorptiometry. Fasting and postchallenge glucose were assessed with a 2-h oral glucose tolerance test. Insulin sensitivity (SI), acute insulin response (AIR), and disposition index ([DI] an index of beta-cell function) were measured by frequently sampled intravenous glucose tolerance test and minimal modeling. Data were analyzed using linear mixed-effects modeling. RESULTS There were no significant effects of breastfeeding categories on adiposity (i.e., total fat mass, total lean tissue mass, percent body fat), fat distribution (visceral and subcutaneous abdominal fat), fasting glucose or 2-h glucose, or insulin dynamics (SI, AIR, and DI) at Tanner pubertal stage 1 or on changes in these variables over pubertal transitions in overweight Latino youth. CONCLUSIONS In this population of high-risk Latino youth, there were no significant protective effects of breastfeeding on adiposity or type 2 diabetes risk factors at Tanner pubertal stage 1 or across advances in maturation.