Laura E. Forbes

Diet quality, nutrition and physical activity among adolescents: the Web-SPAN (Web-Survey of Physical Activity and Nutrition) project.

OBJECTIVE To assess the overall diet quality of a sample of adolescents living in Alberta, Canada, and evaluate whether diet quality, nutrient intakes, meal behaviours (i.e. meal skipping and consuming meals away from home) and physical activity are related. DESIGN A cross-sectional study design. Students completed the self-administered Web-Survey of Physical Activity and Nutrition (Web-SPAN). Students were classified as having poor, average or superior diet quality based on Canadas Food Guide to Healthy Eating (CFGHE). SETTING One hundred and thirty-six schools (37 %) within forty-four public and private school boards (75 %) in Alberta, Canada. SUBJECTS Grade 7 to 10 Alberta students (n 4936) participated in the school-based research. RESULTS On average, students met macronutrient requirements; however, micronutrient and fibre intakes were suboptimal. Median CFGHE food group intakes were below recommendations. Those with poor diet quality (42 %) had lower intakes of protein, fibre and low-calorie beverages; higher intakes of carbohydrates, fat and Other Foods (e.g. foods containing mostly sugar, high-salt/fat foods, high-calorie beverages, low-calorie beverages and high-sugar/fat foods); a lower frequency of consuming breakfast and a higher frequency of consuming meals away from home; and a lower level of physical activity when compared with students with either average or superior diet quality. CONCLUSIONS Alberta adolescents were not meeting minimum CFGHE recommendations, and thus had suboptimal intakes and poor diet quality. Suboptimal nutritional intakes, meal behaviours and physical inactivity were all related to poor diet quality and reflect the need to target these health behaviours in order to improve diet quality and overall health and wellness.

Chronic Disease–Related Lifestyle Risk Factors in a Sample of Canadian Adolescents

This study examined the prevalence, clustering, age trends, and gender differences of chronic-disease related risk factors among a large sample of adolescents (N = 4932) in Alberta, Canada. Approximately 43% of boys and 53% of girls displayed two or more risk factors. Age trends and gender differences were also observed.

Dietary patterns associated with glycemic index and glycemic load among Alberta adolescents

The purpose of this study was to assess the dietary glycemic index (GI) and glycemic load (GL) of adolescents, based on a Web-based 24-h recall, and to investigate dietary predictors of GI and GL. In addition, the relationship between GI and GL and weight status was examined. A Web-based 24-h recall was completed by 4936 adolescents, aged 9-17 years; macronutrient and food group intakes were assessed using the ESHA Food Processor, the Canadian Nutrient File, and Canadas Food Guide. Dietary GI and GL were calculated based on published GI values for foods. Students provided self-reported height and mass. Multiple regression models assessed the ability of food group choices and food behaviours to predict GI and GL. Mean GI was 55 for girls and 56 for boys. Mean GL was 128 for girls and 168 for boys. Food group choices explained 26% of the variation in GI (p < 0.01) and 84% of the variation in GL (p < 0.01). The number of meals per day explained 10% (p < 0.01), and eating meals outside of the home accounted for 2.5% (p < 0.01) of the variation in GL; however, these results disappeared when adjusted for total energy intake. The GI was positively correlated with body mass index in girls (r = 0.05, p = 0.02), and GL was significantly higher among nonoverweight boys than overweight boys. This study identified eating patterns related to daily GI and GL, and suggests certain dietary patterns that could have beneficial effects on health. It also showed that GI and GL were weakly related to weight status.

Adolescent weight status and related behavioural factors: web survey of physical activity and nutrition

Purpose. To identify whether non-overweight students were different from their overweight or obese peers with respect to diet, suboptimal meal behaviours, and physical activity using a self-administered web-based survey. Methods. 4097 adolescents living in Alberta, Canada completed Web-SPAN (Web Survey of Physical Activity and Nutrition). Students were classified as overweight or obese, and differences were described in terms of nutrient intakes, physical activity, and meal behaviours. Results. Non-overweight students consumed significantly more carbohydrate and fibre, and significantly less fat and high calorie beverages, and had a higher frequency of consuming breakfast and snacks compared to overweight or obese students. Both non-overweight and overweight students were significantly more active than obese students. Conclusions. This research supports the need to target suboptimal behaviours such as high calorie beverage consumption, fat intake, breakfast skipping, and physical inactivity. School nutrition policies and mandatory physical education for all students may help to improve weight status in adolescents.

Geography Influences Dietary Intake, Physical Activity and Weight Status of Adolescents

Purpose. The purpose of this study was to assess rural and urban differences in the dietary intakes, physical activity levels and weight status of a large sample of Canadian youth in both 2005 and 2008. Materials and Methods. A cross-sectional study of rural and urban adolescents (n = 10, 023) in Alberta was conducted in both 2005 and 2008 using a web-based survey. Results. There was an overall positive change in nutrient intakes between 2005 and 2008; however, rural residents generally had a poorer nutrient profile than urban residents (P < .001). They consumed less fibre and a greater percent energy from saturated fat. The mean physical activity scores increased among rural youth between 2005 and 2008 (P < .001), while remaining unchanged among urban youth. Residence was significantly related to weight status in 2005 (P = .017), but not in 2008. Conclusion. Although there were small improvements in nutrient intakes from 2005 to 2008, several differences in the lifestyle behaviours of adolescents living in rural and urban areas were found. The results of this study emphasize the importance of making policy and program recommendations to support healthy lifestyle behaviours within the context of the environments in which adolescents live.

Changes in Dietary and Physical Activity Risk Factors for Type 2 Diabetes in Alberta Youth Between 2005 and 2008

ObjectivesUnhealthy dietary and physical inactivity patterns inspired many initiatives promoting healthy youth and healthy schools in Alberta between 2005 and 2008. The purpose of this study was to examine differences in the prevalence of lifestyle risk factors for type 2 diabetes (T2D) between two province-wide samples of Alberta adolescents (2005 and 2008).MethodsThe dietary and physical activity (PA) patterns of Alberta youth were assessed in two cross-sectional studies of grade 7-10 students, one in 2005 (n=4936) and one in 2008 (n=5091), using a validated web-survey. For each diabetes risk factor, participants were classified as either at risk or not at risk, depending on their survey results relative to cut-off values. Chi-square tests and logistic regression models were used to determine differences in risk factor prevalence between 2005 and 2008.ResultsCompared to 2005, mean BMI, energy intake, fat intake, glycemic index (GI) and glycemic load (GL) were lower in 2008 (p<0.05); and carbohydrate, protein, fibre and vegetable and fruit intakes were higher in 2008 (p<0.05). In 2008, a lower proportion of students were: overweight, obese, consuming high GI, high GL, high fat, low fibre, low veg/fruit intake (p<0.05). No differences existed in magnesium or PA levels between the two time points.ConclusionsImprovements were observed between 2005 and 2008 in terms of the proportion of adolescents having specific risk factors for T2D. The cause of these changes could not be determined. Continued monitoring of adolescent lifestyle habits and monitoring of exposure to health promotion programming is recommended.RésuméObjectifsLes habitudes alimentaires malsaines et l’inactivité physique ont inspiré de nombreuses initiatives de promotion de la santé des jeunes et des écoles en Alberta entre 2005 et 2008. Nous avons cherché à examiner les différences dans la prévalence des facteurs de risque liés aux habitudes de vie pour le diabète de type 2 (DT2) entre deux échantillons provinciaux d’adolescents albertains (2005 et 2008).MéthodeLes habitudes d’alimentation et d’activité physique des jeunes de l’Alberta ont été évaluées à la faveur de deux études transversales auprès d’élèves de la 7e à la 10e année, l’une en 2005 (n=4 936) et l’autre en 2008 (n=5 091), à l’aide d’un sondage en ligne validé. Pour chaque facteur de risque du diabète, les participants ont été classés comme étant à risque ou non à risque selon leurs réponses au sondage par rapport aux valeurs limites. Des tests du khi-carré et des modèles de régression logistique ont servi à déterminer les différences dans la prévalence des facteurs de risque entre 2005 et 2008.RésultatsComparativement à 2005, l’IMC moyen, l’apport énergétique, l’apport en matières grasses, l’indice glycémique (IG) et la charge glycémique (CG) étaient plus faibles en 2008 (p<0,05); et les apports en glucides, en protéines, en fibres et en fruits et légumes étaient plus élevés en 2008 (p<0,05). En 2008, une moindre proportion d’élèves était en surpoids ou obèse et consommait une diète avec IG élevé, CG élevée, riche en gras, faible en fibres et faible en fruits et légumes (p<0,05). Aucune différence n’a été relevée dans les niveaux de magnésium ou d’activité physique entre les deux dates.ConclusionsDes améliorations ont été observées entre 2005 et 2008 dans la proportion d’adolescents présentant les facteurs de risque propres au DT2. Nous n’avons pas pu déterminer la cause de ces changements. Il est recommandé de continuer à surveiller les habitudes de vie des adolescents et leur exposition aux programmes de promotion de la santé.

The Association Between Time Spent in Vigorous Physical Activity and Dietary Patterns in Adolescents: A Cross-Sectional Study

BACKGROUND Physical activity interventions targeting weight status have yielded mixed results. This variability may be attributed to compensatory changes in dietary patterns after increasing physical activity (PA) levels. Therefore, we sought to determine whether dietary patterns varied with time spent in vigorous-intensity PA in youth. METHODS Cross-sectional analysis of 330 youth enrolled in a school-based prospective cohort in central Alberta. Physical activity was assessed with waist mounted accelerometers (Actical) worn for 7 days. Main outcomes included consumption of unhealthy foods and the unhealthy food index obtained from a validated web-based 24-hour dietary recall instrument. Secondary outcomes included macronutrient intake, food group (Canadas Food Guide to Healthy Eating) intake, and diet quality. RESULTS Compared with youth participating in < 7 min/ day of vigorous physical activity, those achieving ≥ 7 min/day displayed no change in healthy or unhealthy food consumption. However, linear regression suggests a modest association between diet quality and vigorous-intensity PA. CONCLUSION These data demonstrate that in this cohort of Canadian youth, time spent being physically active is associated with healthier dietary patterns and not with increased consumption of unhealthy foods.