Effects of a low glycemic load or a low-fat dietary intervention on body weight in obese Hispanic American children and adolescents: a randomized controlled trial.

BACKGROUND: In Hispanic children and adolescents, the prevalence of obesity and insulin resistance is considerably greater than in non-Hispanic white children. A low-glycemic load diet (LGD) has been proposed as an effective dietary intervention for pediatric obesity, but to our knowledge, no published study has examined the effects of an LGD in obese Hispanic children. OBJECTIVE: We compared the effects of an LGD and a low-fat diet (LFD) on body composition and components of metabolic syndrome in obese Hispanic youth. DESIGN: Obese Hispanic children (7-15 y of age) were randomly assigned to consume an LGD or an LFD in a 2-y intervention program. Body composition and laboratory assessments were obtained at baseline and 3, 12, and 24 mo after intervention. RESULTS: In 113 children who were randomly assigned, 79% of both groups completed 3 mo of treatment; 58% of LGD and 55% of LFD subjects attended 24-mo follow-up. Compared with the LFD, the LGD decreased the glycemic load per kilocalories of reported food intakes in participants at 3 mo (P = 0.02). Both groups had a decreased BMI z score (P < 0.003), which was expressed as a standard z score relative to CDC age- and sex-specific norms, and improved waist circumference and systolic blood pressure (P < 0.05) at 3, 12, and 24 mo after intervention. However, there were no significant differences between groups for changes in BMI, insulin resistance, or components of metabolic syndrome (all P > 0.5). CONCLUSIONS: We showed no evidence that an LGD and an LFD differ in efficacy for the reduction of BMI or aspects of metabolic syndrome in obese Hispanic youth. Both diets decreased the BMI z score when prescribed in the context of a culturally adapted, comprehensive weight-reduction program.

Effects of high and low glycemic load meals on energy intake, satiety and hunger in obese Hispanic-American youth.

UNLABELLED: Some short-term pediatric studies have suggested beneficial effects of low glycemic load (LGL) meals on feelings of hunger and on energy intake. However, the effects of LGL diets have not been systematically studied in obese Hispanic children, who stand to benefit from successful interventions. OBJECTIVE: To examine the effects of LGL and high-GL (HGL) meals on appetitive responses and ad libitum energy intake of obese Hispanic youth. METHODS: A total of 88 obese Hispanic youth aged 7-15 years were enrolled in a community-based obesity intervention program and randomly assigned to consume meals designed as either LGL (n = 45) or HGL (n = 43). After 12 weeks, participants were admitted for a 24-hour metabolic study. Following the morning test meal, subjects serially reported hunger, fullness, and satiety using a visual analog scale. Blood insulin and glucose were measured. After 5 hours, participants were fed another test meal and given a snack platter from which to eat ad libitum. All test food was weighed and the energy, macronutrients, and glycemic load (GL) of consumed foods were calculated. RESULTS: The HGL group had significantly higher insulin (p = 0.0005) and glucose (p = 0.0001) responses to the breakfast meal compared with the LGL group. There were no significant between-group differences in energy consumed from the snack platter (1303 vs. 1368 kcal, p = 0.5), or in the subjective feelings of hunger (p = 0.3), fullness (p = 0.5) or satiety (p = 0.3) between the two groups. CONCLUSIONS: Our study provides no evidence that, for obese Hispanic youth, changing the GL of the diet affects short-term hunger, fullness, satiety, or energy intake. ClinicalTrials.gov Identifier: NCT01068197.