Changes in Dietary Magnesium Intake and Risk of Type 2 Diabetes Mellitus in Middle School Students: Using Data from the HEALTHY Study.

BACKGROUND: The HEALTHY Study was a multicomponent school-based intervention, designed to prevent type 2 diabetes mellitus (T2DM) in middle-school students. OBJECTIVES: We examined whether the difference in dietary magnesium intake, BMI percentile, and plasma glucose and insulin concentrations from 6th to 8th grade were related in the intervention schools and in the control schools that participated in the HEALTHY Study. METHODS: A total of 2181 ethnically diverse students, from 11.3 to 13.7 y of age, with completed dietary records, BMI percentile, and plasma glucose and insulin concentrations at 6th and 8th grades were included. Dietary magnesium intake was self-reported using the Block Kids FFQ. A hierarchical multiple regression model was used to determine whether the differences in dietary magnesium intake, BMI percentile, and plasma glucose and insulin concentrations from 6th to 8th grades were related, while adjusting for dietary calcium intake and total energy intake. RESULTS: The difference in dietary magnesium intake was significantly related to changes in BMI percentile from 6th to 8th grade in intervention and in control schools [intervention: ß: -0.07; 95% CI: -0.58, -0.02; P = 0.03; R2 (regression coefficient effect size): 0.14; 95% CI for R2: 0.10, 0.17; control: ß: -0.08; 95% CI: -0.63, -0.09; P = 0.01; R2: 0.12; 95% CI for R2: 0.08, 0.15]. The difference in dietary magnesium intake was not related to plasma glucose and insulin concentrations in intervention and in control schools. CONCLUSIONS: We conclude that a multicomponent intervention was associated with reduced risk of T2DM, and that this association may be modulated, in part, by magnesium. The differences in dietary magnesium intake from 6th to 8th grade were negatively related to changes in BMI percentile among middle-school students.

Dietary magnesium intake in relation to body mass index and glycemic indices in middle school students from the HEALTHY Study.

BACKGROUND: Data on dietary magnesium intake on the risk of type 2 diabetes mellitus (T2DM) among children and adolescents is limited. AIM: We examined whether dietary magnesium intake was related to body mass index (BMI) percentile, and glycemic indices at baseline and at end of the HEALTHY Study for both intervention and control schools. The HEALTHY Study was a multi-component, school-based intervention, to prevent T2DM in children and adolescents from 6th to 8th grades. METHODS: A secondary data analyses of 2181 ethnically diverse students with completed dietary records, BMI percentile, and plasma insulin and glucose concentrations at baseline (6th grade) and end of study (8th grade) were included from the HEALTHY Study. Dietary magnesium intake was self-reported using the Block Kids Food Frequency Questionnaire. A hierarchical multiple regression model was used to determine the relationships between dietary magnesium intake, BMI percentile, and glycemic indices at baseline and end of the HEALTHY Study, adjusting for magnesium intake from supplements, total energy intake, and fitness level. RESULTS: Dietary magnesium intake was related to BMI percentile at baseline and at end of the HEATHY Study (ß = -0.05, 95% CI = -0.02 to 0, p = 0.04; ß = -0.06, 95% CI = -0.02 to -0.003, p = 0.004); R 2 [regression coefficient effect size] = 0.03; R 2 = 0.06). Dietary magnesium intake was not related to plasma insulin and glucose concentrations at baseline and end of the HEALTHY Study. CONCLUSION: Dietary magnesium intake was inversely related to BMI percentile among middle school students from the HEALTHY Study. Research is required to evaluate the dose-response relationship between fruit and vegetable consumption (good sources of magnesium) and risk of T2DM in children and adolescents. This relationship also needs to be explored among different BMI categories.

Sedentary behavior time as a predictor of hemoglobin A1c among adults, 40 to 59 years of age, living in the United States: National Health and Nutrition Examination Survey 2003 to 2004 and 2013 to 2014.

BACKGROUND: Sedentary behavior activities have been associated with an increased risk of type 2 diabetes. Aim: Our aim was to determine whether sedentary behavior time (SBT) is predictive of hemoglobin A1c (HbA1c) ≥ 6.5% (48 mmol/mol). METHODS: We used cross-sectional data, adults 40 to 59 years of age, from the National Health and Nutrition Examination Survey (NHANES) for 2003 to 2004 and 2013 to 2014. Responses to questions on the Physical Activity Questionnaire regarding time watching television/videos, and time spent sitting in front of a computer per day were compiled into tertiles. Binary logistic regression analysis was used to determine whether SBT was a predictor of a HbA1c ≥ 6.5% adjusting for age, sex, race and ethnicity, and body mass index. RESULTS: In a univariate model, adults reporting ≥ 8 hours of SBT in NHANES 2003-2004 had 2.02 increased odds of a HbA1c ≥ 6.5% (OR = 2.02, 95% CI: 1.31, 3.13, p < 0.0001) compared to adults reporting ≤ 3 hours. After adjusting the regression model for age, sex, race and ethnicity, and body mass index, adults reporting ≥ 8 hours of SBT in NHANES 2003 to 2004 had 1.72 increased odds of HbA1c ≥ 6.5% (OR = 2.02, 95% CI: 1.10, 2.68, p < 0.0001) compared to adults reporting ≤ 3 hours of SBT. Reported SBT was not a predictor of HbA1c ≥ 6.5% for NHANES 2013 to 2014. CONCLUSION: Reported SBT was a predictor of HbA1c ≥ 6.5% among adults, 40 to 59 years of age, in NHANES 2003 to 2004, but was not a predictor in 2013 to 2014.

Relationships between sensory modulation and social supports and health-related quality of life.

OBJECTIVE: We explored the relationships between sensory modulation and health-related quality of life (HRQOL), social supports, and mental health symptoms of anxiety and depression. METHOD: Twenty-eight adult volunteers ages 18-60 participated in the study. Fourteen adults were sensory overresponsive (SOR), and 14 adults in a matched comparative group were not sensory overresponsive (NSOR). All participants were tested using self-administered measures of sensory processing. RESULTS: Significant differences were found between SOR and NSOR groups on symptoms of anxiety, depression, and 4 of 8 indicators of HRQOL. CONCLUSION: Several analyses exploring the relationships among the variables tested suggest that sensory response style, whether comparing SOR and NSOR groups or exploring the correlation of the response quadrants of the Adolescent/Adult Sensory Profile, appears significantly and differentially related to symptoms of affective mental health and quality-of-life indicators, including social participation.

Psychosocial factors and health perceptions in parents and children who are overweight or obese.

This study examined the relationships among weight status (BMI), health perceptions, and psychosocial characteristics in children, parents, and parent-child dyads. A convenient sample of 114 parent-child dyads participated. All children were overweight or obese. Parents and children completed questionnaires by self-report or interview. Questionnaires included the Parenting Stress Index-Short Form (PSI), the Parents' Stage of Change (SOC) Questionnaire, and the Pediatric Quality of Life Inventory (PedsQL). Child's mean age was 10.34 years (s.d. = 1.87), mean BMI was 28.13 kg/m(2) (s.d. = 5.46), and mean BMI z-score was 2.17 (s.d. = 0.38). Parent mean age was 37.28 years (s.d. = 12.66) and mean BMI was 34.07 kg/m(2) (s.d. = 8.18). Most parents (68.5%) reported that they and their children (70.7%) were African American and many (44.3%) reported that they and their children were Hispanic. Significant correlations included: child health perceptions and child BMI (r = 0.309, P < 0.001) and parent perception of weight and parent BMI (r = 0.691, P < 0.001). For parent-child dyads, one correlation approached significance (child health perceptions and parent stage of change (r = -0.269, P < 0.01). Findings suggest that characteristics of parent-child dyads may be important considerations in the management of childhood obesity.

Effects of sensory integration intervention on self-stimulating and self-injurious behaviors.

This study compared the effects of occupational therapy, using a sensory integration (SI) approach and a control intervention of tabletop activities, on the frequency of self-stimulating behaviors in seven children 8-19 years of age with pervasive developmental delay and mental retardation. Daily 15-min videotape segments of the subjects were recorded before, immediately after, and 1 hour after either SI or control interventions performed during alternating weeks for 4 weeks. Each 15-min video segment was evaluated by investigators to determine the frequency of self-stimulating behaviors. The results indicate that self-stimulating behaviors were significantly reduced by 11% one hour after SI intervention in comparison with the tabletop activity intervention (p = 0.02). There was no change immediately following SI or tabletop interventions. Daily ratings of self-stimulating behavior frequency by classroom teachers using a 5-point scale correlated significantly with the frequency counts taken by the investigators (r = 0.32, p < 0.001). These results suggest that the sensory integration approach is effective in reducing self-stimulating behaviors, which interfere with the ability to participate in more functional activities.

Use of phosphocreatine kinetics to determine the influence of creatine on muscle mitochondrial respiration: an in vivo 31P-MRS study of oral creatine ingestion.

Recent human isolated muscle fiber studies suggest that phosphocreatine (PCr) and creatine (Cr) concentrations play a role in the regulation of mitochondrial respiration rate. To determine whether similar regulatory mechanisms are present in vivo, this study examined the relationship between skeletal muscle mitochondrial respiration rate and end-exercise PCr, Cr, PCr-to-Cr ratio (PCr/Cr), ADP, and pH by using (31)P-magnetic resonance spectroscopy in 16 men and women (36.9 +/- 4.6 yr). The initial PCr resynthesis rate and time constant (T(c)) were used as indicators of mitochondrial respiration after brief (10-12 s) and exhaustive (1-4 min) dynamic knee extension exercise performed in placebo and creatine-supplemented conditions. The results show that the initial PCr resynthesis rate has a strong relationship with end-exercise PCr, Cr, and PCr/Cr (r > 0.80, P < 0.001), a moderate relationship with end-exercise ADP (r = 0.77, P < 0.001), and no relationship with end-exercise pH (r = -0.14, P = 0.34). The PCr T(c) was not as strongly related to PCr, Cr, PCr/Cr, and ADP (r < 0.77, P < 0.001-0.18) and was significantly influenced by end-exercise pH (r = -0.43, P < 0.01). These findings suggest that end-exercise PCr and Cr should be taken into consideration when PCr recovery kinetics is used as an indicator of mitochondrial respiration and that the initial PCr resynthesis rate is a more reliable indicator of mitochondrial respiration compared with the PCr T(c).

Muscle metabolism with blood flow restriction in chronic fatigue syndrome.

The purpose of this study was to determine whether chronic fatigue syndrome (CFS) is associated with reduced blood flow and muscle oxidative metabolism. Patients with CFS according to Centers for Disease Control criteria (n = 19) were compared with normal sedentary subjects (n = 11). Muscle blood flow was measured in the femoral artery with Doppler ultrasound after exercise. Muscle metabolism was measured in the medial gastrocnemius muscle with (31)P-magnetic resonance spectroscopy. Muscle oxygen saturation and blood volume were measured using near-infrared spectroscopy. CFS and controls were not different in hyperemic blood flow or phosphocreatine recovery rate. Cuff pressures of 50, 60, 70, 80, and 90 mmHg were used to partially restrict blood flow during recovery. All pressures reduced blood flow and oxidative metabolism, with 90 mmHg reducing blood flow by 46% and oxidative metabolism by 30.7% in CFS patients. Hyperemic blood flow during partial cuff occlusion was significantly reduced in CFS patients (P < 0.01), and recovery of oxygen saturation was slower (P < 0.05). No differences were seen in the amount of reduction in metabolism with partially reduced blood flow. In conclusion, CFS patients showed evidence of reduced hyperemic flow and reduced oxygen delivery but no evidence that this impaired muscle metabolism. Thus CFS patients might have altered control of blood flow, but this is unlikely to influence muscle metabolism. Furthermore, abnormalities in muscle metabolism do not appear to be responsible for the CFS symptoms.

Blood flow and muscle metabolism in chronic fatigue syndrome.

The purpose of this study was to determine if chronic fatigue syndrome (CFS) is associated with reduced blood flow and oxidative delivery to skeletal muscle. Patients with CFS according to CDC (Center for Disease Control) criteria ( n =19) were compared with normal sedentary subjects ( n =11). Muscle blood flow was measured with Doppler ultrasound after cuff ischaemia and exercise. Muscle oxygen delivery was measured as the rate of post-exercise and post-ischaemic oxygen-haem resaturation. Oxygen-haem resaturation was measured in the medial gastrocnemius muscle using continuous wavelength near-IR spectroscopy. Muscle metabolism was measured using (31)P magnetic resonance spectroscopy. CFS patients and controls were not different in the peak blood flow after cuff ischaemia, the rate of recovery of phosphocreatine after submaximal exercise, and the rate of recovery of oxygen saturation after cuff ischaemia. In conclusion, CFS patients showed no deficit in blood flow or oxidative metabolism. This suggests that CFS symptoms do not require abnormal peripheral function.