Pre-meal active video game playing increased subjective appetite but not food intake in children and adolescents.

OBJECTIVE: Sedentary video game playing (VGP) and caloric preloads in the pre-meal environment have been shown to influence short-term food intake (FI) regulation in children. Other factors that may affect FI control include physical activity and/or heightened emotion. Therefore, we examined the effects of a glucose preload and 30 min of active VGP (aVGP) on subjective appetite, short-term FI, and subjective emotions in 9-14 year-old children. METHODS: On four test mornings approximately one-week apart, twenty-seven children (sex: 15M, 12F; age: 11.3 ± 0.3 years; BMI percentile: 55.3 ± 6.1%) consumed a standardized breakfast two hours prior to consuming 250 mL of either a 50 g glucose preload or Sucralose® control. Following the preload, participants participated in 30 min of quiet sitting or aVGP. Energy expenditure was measured during aVGP via indirect calorimetry. FI from an ad libitum pizza meal was measured after each test condition. Subjective appetite and emotions were measured at baseline (0 min), during treatment (15min), and immediately before the test meal (30 min). RESULTS: aVGP did not affect FI, but the glucose preload decreased FI compared with the sucralose control (∆ = 157 kcal, <0.001). Although not statistically significant (p=0.12), caloric compensation was lower following the glucose preload in the aVGP condition. Subjective appetite increased with time, and was higher in the sucralose control + aVGP condition (p=0.05). Change from baseline subjective emotion scores of anger and excitement were higher (p=0.03) and lower (p=0.02) after aVGP, respectively. CONCLUSIONS: Neither short-term FI nor net energy balance were affected by low-intensity aVGP (energy expenditure of 34 kcal). These findings suggest that a short bout of low-intensity aVGP does not alter energy balance during the study measurement period, and may not support achieving or maintaining healthy weights in children. However, future longitudinal studies are needed to confirm such advice.

The impact of school policies and practices on students' diets, physical activity levels and body weights: A province-wide practice-based evaluation.

OBJECTIVES: To assess what health promotion policies and practices were adopted by schools in Nova Scotia and the extent that these policies and practices affected the diet quality, physical activity (PA) and weight status of students. METHODS: We developed and administered a 'school practice assessment tool' to assess the presence of 72 different school-based health promotion policies and practices. Surveys were conducted in 2003 and 2011 to assess diet, PA and weight status in approximately 10,000 grade 5 students. We used multilevel regression methods to examine changes in these outcomes across schools with varying levels of health promotion policies and practices between the two time-points. RESULTS: Between 2003 and 2011 the diet quality of students improved, PA decreased and the prevalence of childhood obesity increased. Although we did not find consistent or significant favourable benefits resulting from higher implementation levels, we did observe fewer negative trends among schools at higher levels of implementation. CONCLUSION: Our results build on the current gap in knowledge on the impact of Health Promoting Schools (HPS) implementation through population health interventions, but there is a continued need for further evaluation and monitoring of school policies to understand how HPS practices are supporting healthier eating and PA for students.

Cannabis-associated myocardial infarction in a young man with normal coronary arteries.

BACKGROUND: The use of cannabis is not usually regarded as a risk factor for acute coronary syndrome. However, several cases of myocardial infarction (MI) associated with cannabis use have been reported in the scientific literature. The etiology of this phenomenon is not known. OBJECTIVES: To present a case of cannabis-associated MI in which atherosclerotic coronary disease was excluded as a potential etiology by intravascular ultrasound examination, and briefly review the other possible mechanisms by which this effect may be mediated. CASE REPORT: We present the case of a previously healthy 21-year-old man who regularly smoked cannabis and presented to the Emergency Department with ST-elevation myocardial infarction after participating in a sport. He was also a cigarette smoker, but had no other conventional cardiovascular risk factors. At coronary angiography, a large amount of thrombus was found in the left anterior descending coronary artery. He recovered with medical treatment, and subsequent intravascular ultrasound examination showed no evidence of atherosclerosis at the site of the thrombus. CONCLUSION: Cannabis-associated MI is increasingly recognized. The etiology is unclear, but we believe this is the first report of the phenomenon where atherosclerotic plaque rupture has been excluded as the cause with a high degree of confidence.

Obesity, lifestyle and socio-economic determinants of vitamin D intake: a population-based study of Canadian children.

OBJECTIVE: Vitamin D intake in childhood is primarily for the prevention of rickets. Inconsistent evidence has associated adequate blood concentrations with a decreased risk of certain health conditions. Further, obese individuals may have lower vitamin D status. The estimated average requirement (EAR) for children recently doubled to 400 IU/day. Our aim was to examine dietary intake of vitamin D in different body mass index (BMI) categories, in addition to assessing determinants. METHODS: Data from two provincial surveys of grade 5 children, including a food frequency questionnaire and measured BMI, were used. Rao-Scott chi-square statistic tested the bivariate association between provinces and adequate dietary vitamin D intake. Key correlates were examined using multi-level logistic regression. RESULTS: Those below the EAR differed between Alberta (78%) and Nova Scotia (81%). Those drinking <2 glasses of milk/day had 0.02 times the odds of meeting the EAR (95% CI: 0.01-0.02) compared to those drinking more. No significant difference was observed for BMI, though those consuming <1 glass of milk/day were more likely to be obese than those consuming ≥2 glasses/day. Income and physical activity were negatively correlated with meeting the EAR. CONCLUSION: Many children did not meet the EAR for vitamin D from dietary sources and milk consumption was an important determinant. Given trends towards a more sedentary lifestyle and limited sun exposure, we recommend prioritizing public health efforts to support dietary vitamin D intake alongside interventions to increase physical activity and reduce sedentary behaviour. Further investigation is required to determine the need for targeted strategies for obese children.

Adolescents' diets do not comply with 2007 Canada's food guide recommendations.

This study evaluated the eating behaviours of students in grade six and, three years later when they were in grade nine, relative to the recommendations of Canada's 2007 Food Guide. Students completed a self-administered questionnaire on eating behaviours in 2002 (n=647) and again in 2005 (n=520) as part of Better Beginnings, Better Futures, a primary prevention initiative among economically disadvantaged communities. McNemar analysis and X(2) analysis were used to assess differences in compliance with the recommendations of the Food Guide. Differences in the mean number of servings of the four food groups and the Other Foods group were examined using independent sample t-tests and paired t tests. In grade six, 5% of males and 7% of females met the minimum number of recommended servings for all four food groups. By grade nine this had dropped to 0.4% and 2% respectively. Among males who completed the questionnaire in both grade six and grade nine there was a decline in the mean number of daily servings for all four food groups. For females a similar trend was observed. The likelihood of adolescents meeting all Food Guide recommendations decreased from grade six to grade nine.