Selection of medical students: an Australian perspective.
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Biomedical subjects
Publications and source records attributed to M Story.
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OBJECTIVES: This study aimed to assess the prevalence of perceived weight-teasing and associations with unhealthy weight-control behaviors and binge eating in a population-based sample of youth. Particular focus was placed on overweight youth, who may be most vulnerable to weight-teasing. METHODS: The study population included 4746 adolescents from St Paul/Minneapolis public schools who completed surveys and anthropometric measurements as part of Project EAT, a population-based study of eating patterns and weight concerns among teens. RESULTS: There were statistically significant associations between perceived weight-teasing and weight status; both overweight and underweight youth reported higher levels of teasing than average weight youth. Very overweight youth (body mass index (BMI) > or = 95th percentile) were most likely to be teased about their weight; 63% of very overweight girls, and 58% of very overweight boys reported being teased by their peers, while weight-teasing by family members was reported by 47% of these girls and 34% of these boys. Youth who were teased about their weight, particularly overweight girls, reported that it bothered them. Perceived weight-teasing was significantly associated with disordered eating behaviors among overweight and non-overweight girls and boys. For example, among overweight youth, 29% of girls and 18% of boys who experienced frequent weight-teasing reported binge-eating as compared to 16% of girls and 7% of boys who were not teased. CONCLUSIONS: Many adolescents, in particular those who are overweight, report being teased about their weight and being bothered by the teasing. Weight-teasing is associated with disordered eating behaviors that may place overweight youth at increased risk for weight gain. Educational interventions and policies are needed to curtail weight-related mistreatment among youth.
OBJECTIVE: To assess the relationships between mothers' reports of dieting and encouraging adolescents to diet and adolescents' reports of their own dieting practices and weight-related concerns. DESIGN: Cross-sectional study of parent interviews and adolescent surveys in an ethnically-diverse sample. SUBJECTS: A total of 810 adolescents (n=381 boys and n=429 girls) and their mothers. RESULTS: Mothers' dieting was associated with their adolescent girls' weight-related concerns and behaviors, but these associations were not significant after adjusting for girls' body mass index (BMI). In contrast, mothers' encouragement for sons to diet was associated with sons' binge eating, dieting and other weight-control behaviors, even after controlling for sons' BMI. Compared with mothers who did not encourage their child to diet, mothers who encouraged their child to diet were significantly heavier women and were more likely to view their child as overweight. Forty-three percent of boys and 46% of girls who were encouraged by their mothers to diet were classified as nonoverweight by federal guidelines. CONCLUSIONS: Boys who are encouraged by their mothers to diet may be at risk for health-compromising eating and dieting behaviors, particularly binge-eating, fasting, eating a little bit of food and skipping meals. Parents who are concerned about their children's weight should be educated to encourage healthy eating habits and physical activity to promote their children's health, including healthy weight control.
PURPOSE: The purpose of this report is to provide current perspectives on studies of DNA damage and cell cycle response after ionizing radiation, and their applications in radiation oncology. METHODS AND MATERIALS: Presentations at the Seventh Annual Radiation Oncology Workshop, held at the International Festival Institute at Round Top, TX, were summarized. RESULTS: Eighteen speakers presented their current work covering a wide range of studies on cellular responses to ionizing radiation. These presentations and discussions form the framework of our report. CONCLUSION: In response to ionizing radiation, cells immediately activate a series of biochemical pathways that promote cell survival while maintaining genetic integrity. The main cellular defense system against ionizing radiation exposure is composed of two distinct types of biochemical pathways, that is, the DNA damage cell cycle checkpoint pathways and the DNA repair pathways. The DNA damage checkpoint pathways are activated directly by DNA damage, while the repair pathways are constitutively active and are likely modulated by checkpoint signals. Discussions here emphasize that the ATM protein is a central component of the ionizing radiation-responsive pyramid and is essential for activating divergent molecular responses that involve transcriptional regulation, cell cycle arrest, and modulation of DNA repair. The relationship between homologous recombinational repair and nonhomologous end joining of double-strand breaks is also discussed.
This article describes a process for establishing school nutrition advisory councils (SNACs) as an integral part of a school environment approach to promoting the nutritional health of students. The application of social cognitive theory as the conceptual framework for SNACs is discussed and the steps for establishing councils, including describing the school food environment, recruiting council members and convening the council, are reviewed. Actions taken by SNACs to positively affect the school nutrition environment are also described. SNACs are 1 component of the Teens Eating for Energy and Nutrition at School (TEENS) study, a group randomized, school-based intervention trial conducted in 16 middle schools in the Minneapolis-St Paul, Minn, metropolitan area. TEENS seeks to promote healthful dietary behaviors among young adolescents to reduce future cancer risk. Primary outcome measures include increasing fruit and vegetable intake and decreasing fat consumption. SNACs were established in the intervention schools to assess the overall school food environment and to advance school-level policy that promotes a healthful food environment.
Childhood obesity may be seen as a marker for high-risk dietary and physical inactivity practices. Recent increases in the prevalence of overweight and obesity among American children are not limited to one age, gender, or ethnic group, which suggests that unique behaviors of the members of various racial or ethnic subgroups of the population are unlikely to be the major contributing factors. Rather, it seems that environmental changes promoting increased energy intake and decreased energy output are occurring and have widespread impact on children from various backgrounds. Although no ethnic group is immune from the current shift in energy balance, differential rates of overweight seem to exist among ethnic groups. National probability samples of African-American, Hispanic, and white children in the United States provide clear evidence that white children are at lower risk for childhood overweight than are African-American or Hispanic children. Of concern is the lack of national data on the prevalence of overweight and obesity for Native-American and Asian-American groups. Also of concern is the aggregation of racial and ethnic subgroups, which may render prevalence rates meaningless. This possibility is clearly true with some surveys of weight status that combine diverse populations, such as Asians and Pacific Islanders, into one group. The high rates of obesity in African-American, Hispanic, and Native-American children are of concern. Although parental SES is associated inversely with childhood obesity among whites, higher SES does not seem to protect African-American and Hispanic children against obesity. In these groups, childhood obesity does not seem to be associated significantly with parental income and education. Health consequences of childhood obesity include a higher prevalence of type 2 diabetes and an increased risk for adverse levels of lipids, lipoproteins, and blood pressure. The effects of recently reported unprecedented levels of childhood overweight on subsequent risk for obesity in middle age are not known until future longitudinal data can be collected. It seems likely, however, that future health consequences of current early and severe childhood obesity will be staggering. Funding for adult follow-up of longitudinal studies of high-risk African American, Hispanic, and Native-American children is needed urgently to provide information on the long-term effects of childhood obesity. Halting the obesity epidemic is a formidable task, but the success in recent decades of drastically reducing childhood undernutrition offers hope and should spur similar action and leadership efforts. Promotion of efforts to reduce excess caloric intake with efforts to increase energy expenditure should receive paramount attention in the design of health programs. Given the relatively few published obesity-prevention and treatment studies that are designed to address specific cultural issues, it is important to promote the development of culturally appropriate intervention strategies that are shown to be effective among youth of diverse backgrounds. Although the dietary and activity goals will be similar, parental, family, and community messages and techniques grounded in cultural traditions and norms will be different for each ethnic group. This approach is crucial in the United States, a country with an increasingly diverse population.
OBJECTIVES: (1) To examine associations between binge and purge behavior and sexual and physical abuse among adolescents; (2) to determine if these associations remain significant after controlling for sociodemographic and anthropometric characteristics; and (3) to identify aspects of abuse associated with binge and purge behavior. METHOD: A nationally representative sample of 6728 adolescents in 5th-12th grades completed the Commonwealth Fund Survey of the Health of Adolescent Girls and Boys. RESULTS: Binge and purge behavior was nearly twice as prevalent among girls (13%) as boys (7%), and was significantly associated with all abuse types (physical, sexual, or both). Associations were strongest among individuals who had experienced both physical and sexual abuse [odds ratios 4.28 (girls) and 8.25 (boys)]. Differences in binge and purge behavior by gender and type of abuse across abuse characteristics were limited. A higher percentage of abused youth that did not discuss their abuse reported binge-purge behavior than those who did discuss their abuse. Abused girls and boys who did talk to someone about the abuse most often discussed the abuse with their best friend (42.5% and 18.0%, respectively), their mother (38.8% and 32.2%, respectively), and their friends (27.2% and 19.5%, respectively). DISCUSSION: Being physically and/or sexually abused was associated with greater likelihood for engaging in binge and purge behaviors. Discussing the abuse experience with another person may help to reduce binge-purge behavior, as abused adolescents who did not discuss the abuse were more likely to report binge-purge behavior than those who did discuss their abuse.
PURPOSE: To study associations between binge/purge and weight loss behaviors and "developmental assets" among adolescent girls and boys. METHODS: The Search Institute's Profile of Student Life: Attitudes and Behaviors self-report questionnaire was administered to 48,264 girls and 47,131 boys in grades 6 through 12 at schools in 213 cities or towns across the United States. The 156-item questionnaire measured 40 "developmental assets," or protective factors associated with successful adolescent development. Developmental assets were examined using multiple logistic regression among students who reported binge/purge behaviors, weight loss behavior, both, or neither. RESULTS: Developmental assets related to positive identity were the strongest discriminators of binge/purge and weight loss behaviors in both girls and boys. Girls who reported binge/purge and weight loss behaviors were about half as likely to report feeling a sense of purpose [odds ratio (OR) = 0.45, 95% confidence interval (CI) = 0.40, 0.50] and high self-esteem (OR = 0.55, 95% CI = 0.49, 0.61), compared with girls not reporting either of these behaviors. Among boys the ORs were: sense of purpose OR = 0.53 (95% CI = 0.46, 0.61) and self-esteem OR = 0.76 (95% CI = 0.65, 0.88). Assets related to values about abstinence from alcohol, drugs, or sex ("restraint") were also significant correlates. Girls and boys who reported these values were less likely to report binge/purge and weight loss behaviors, compared with those who did not report these values (girls: OR = 0.56, 95% CI = 0.50, 0.63; boys: OR = 0.83, 95% CI = 0.70, 0.97). CONCLUSIONS: Internal assets such as self-esteem, sense of purpose, and values related to abstinence from alcohol and sex appear to be protective against unhealthy eating behaviors and may reflect a general resilience that buffers against a broad range of health risk behaviors.
PURPOSE: To examine the prevalence of adolescents' vegetarianism in a multiethnic, urban population, and its correlates with demographic, personal, weight-related, and behavioral factors. METHODS: Self-report and anthropometric data were collected from a representative sample of 4746 adolescents from 31 public middle schools and high schools in the Twin Cities area of Minnesota. Students answered questions concerning vegetarianism, food and weight, and health behaviors. Height and weight were directly measured. Comparisons were made between self-reported vegetarians and nonvegetarians; these analyses also assessed gender and race/ethnicity interactions. In the second set of analyses, demographic and behavioral characteristics of more restricted and semi-vegetarians were examined. Analyses were done by logistic regression. RESULTS: Teenage vegetarians comprise about 6% of the sample. The vegetarians were more likely than nonvegetarians to be female, not black, weight- and body-conscious, dissatisfied with their bodies, and involved in a variety of healthy and unhealthy weight control behaviors. Vegetarians more often reported having been told by a physician that they had an eating disorder and were more likely to have contemplated and attempted suicide. Vegetarian males were found to be an especially high risk group for unhealthy weight control practices. Few ethnic group differences among vegetarians were noted. Adolescents who did not eat chicken and fish were at lower risk than those who also ate chicken and fish. CONCLUSIONS: Adolescent vegetarians are at greater risk than others for involvement in unhealthy and extreme weight control behaviors. Vegetarian males are at particularly high risk. Vegetarianism among adolescents may therefore be a signal for preventive intervention. Adolescents who choose to become vegetarians may also need to learn how to healthfully do so.
OBJECTIVE: This study examined dieting, weight perceptions, and self-efficacy to eat healthy foods and engage in physical activity and their relationships to weight status and gender among American Indian elementary schoolchildren. RESEARCH METHODS AND PROCEDURES: Data for this study were collected as part of the baseline examination for the Pathways study. Participants were 1441 second- through third-grade American Indian children in 41 schools representing seven tribes in Arizona, New Mexico, and South Dakota who filled out a questionnaire and had heights and weights taken. RESULTS: Forty-two percent of the children were overweight or obese. No differences were found between overweight/obese and normal weight children for healthy food intentions or self-efficacy. Heavier children (especially those with body mass index > 95th percentile) were more likely to have tried to lose weight or were currently trying to lose weight. No gender differences were found. Normal weight children chose a slightly heavier body size as most healthy compared with overweight/obese children. DISCUSSION: The results indicate that children are concerned about their weight and that weight modification efforts are common among overweight American Indian children. School, community, and family-based programs are needed to help young people adopt lifelong healthful eating and physical activity practices.
OBJECTIVES: The purpose of this research was to examine the social, educational, and psychological correlates of weight status in an adolescent population. It was hypothesized that obese adolescents would differ on psychological, social, and educational variables compared with their non-overweight peers. RESEARCH METHODS AND PROCEDURES: In this cross-sectional study, a population-based sample of 4742 male and 5201 female public school students in the 7th, 9th, and 11th grades responded anonymously to a classroom administered questionnaire. Body mass index was calculated from self-reported height and weight and categorized into four classes of weight status: underweight (<15th percentile), average weight (15th to 85th percentile), overweight (>85th to 95th percentile), and obese (>95th percentile). The questionnaire also included questions about social experiences, psychological well-being, educational experiences, and future goals. Associations of weight status with social, psychological, and educational variables and future goals were explored. RESULTS: After adjustment for grade level, race, and parental socioeconomic status, obese girls, when compared with their average weight counterparts, were 1.63 (95% confidence interval [CI]: 1.16, 2.30) times less likely to hang out with friends in the last week, 1.49 (95% CI: 1.12, 1.98) times more likely to report serious emotional problems in the last year, 1.79 (95% CI: 1.20, 2.65) times more likely to report hopelessness, and 1.73 (95% CI: 1.21, 1.98) times more likely to report a suicide attempt in the last year. Obese girls were also 1.51 (95% CI: 1.09, 2.10) times more likely to report being held back a grade and 2.09 (95% CI: 1.35, 3.24) times more likely to consider themselves poor students compared with average weight girls. Compared with their average weight counterparts, obese boys were 1.91 (95% CI: 1.43, 2.54) times less likely to hang out with friends in the last week, 1.34 (95% CI: 1.06, 1.70) times more likely to feel that their friends do not care about them, 1.38 (95% CI: 1.08, 1.76) times more likely to report having serious problems in the last year, 1.46 (95% CI: 1.05, 0.03) times more likely to consider themselves poor students, and 2.18 (95% CI: 1.45, 3.30) times more likely to expect to quit school. Compared with average weight boys, underweight boys were 1.67 (95% CI: 1.30, 2.13) times more likely to report hanging out with friends in the last week, 1.22 (95% CI: 1.01, 1.49) times more likely to report disliking school, and 1.40 (95% CI: 1.06, 1.86) times more likely to consider themselves poor students. DISCUSSION: Associations of weight status with social relationships, school experiences, psychological well-being, and some future aspirations were observed. Among girls, the pattern of observations indicates that obese girls reported more adverse social, educational, and psychological correlates. Obese as well as underweight boys also reported some adverse social and educational correlates. These findings contribute to an understanding of how adolescent experiences vary by weight status and suggest social and psychological risks associated with not meeting weight and body shape ideals embedded in the larger culture.
OBJECTIVE: To examine demographic, behavioral and dietary correlates of frequency of fast food restaurant use in a community-based sample of 4746 adolescent students. DESIGN: A survey was administered to students in classrooms at 31 secondary schools in a large metropolitan area in Minnesota, United States. Height and body weight were measured. SUBJECTS: Students in grades 7-12 who were enrolled in participating schools, had parental consent and were in attendance on the day of data collection. MEASUREMENTS: Frequency of fast food restaurant use (FFFRU), dietary intake, and demographic and behavioral measures were self-reported. Dietary intake was assessed using a semi-quantitative food frequency questionnaire. Height and body weight were directly measured. RESULTS: FFFRU was positively associated with intake of total energy, percent energy from fat, daily servings of soft drinks, cheeseburgers, french fries and pizza, and was inversely associated with daily servings of fruit, vegetables and milk. FFFRU was positively associated with student employment, television viewing, home availability of unhealthy foods, and perceived barriers to healthy eating, and was inversely associated with students' own and perceived maternal and peer concerns about healthy eating. FFFRU was not associated with overweight status. CONCLUSIONS: FFFRU is associated with higher energy and fat intake among adolescents. Interventions to reduce reliance on fast food restaurants may need to address perceived importance of healthy eating as well as time and convenience barriers.
Obesity has increased dramatically over the past two decades and currently about 50% of US adults and 25% of US children are overweight. The current epidemic of obesity is caused largely by an environment that promotes excessive food intake and discourages physical activity. This chapter reviews what is known about environmental influences on physical activity and eating behaviors. Recent trends in food supply, eating out, physical activity, and inactivity are reviewed, as are the effects of advertising, promotion, and pricing on eating and physical activity. Public health interventions, opportunities, and potential strategies to combat the obesity epidemic by promoting an environment that supports healthy eating and physical activity are discussed.
OBJECTIVES: This study examined the effects of pricing and promotion strategies on purchases of low-fat snacks from vending machines. METHODS: Low-fat snacks were added to 55 vending machines in a convenience sample of 12 secondary schools and 12 worksites. Four pricing levels (equal price, 10% reduction, 25% reduction, 50% reduction) and 3 promotional conditions (none, low-fat label, low-fat label plus promotional sign) were crossed in a Latin square design. Sales of low-fat vending snacks were measured continuously for the 12-month intervention. RESULTS: Price reductions of 10%, 25%, and 50% on low-fat snacks were associated with significant increases in low-fat snack sales; percentages of low-fat snack sales increased by 9%, 39%, and 93%, respectively. Promotional signage was independently but weakly associated with increases in low-fat snack sales. Average profits per machine were not affected by the vending interventions. CONCLUSIONS: Reducing relative prices on low-fat snacks was effective in promoting lower-fat snack purchases from vending machines in both adult and adolescent populations.
OBJECTIVE: To examine associations between disordered eating behaviors and a range of familial/psychosocial factors, including sexual and physical abuse experiences, among adolescent girls and boys. METHOD: A statewide representative sample of 9,943 students in Grades 7, 9, and 11 in Connecticut completed a comprehensive survey on adolescent health within their schools. The present analysis focused on measures of disordered eating, sexual and physical abuse, familial factors, peer support, and depressive symptoms. RESULTS: Youth at increased risk for disordered eating included those who perceived family communication, parental caring, and parental expectations as low and those who reported sexual or physical abuse experiences. After adjusting for differences in familial/psychosocial factors, associations between abuse experiences and disordered eating were weakened. However, youth who reported sexual abuse were still at increased risk for disordered eating, even after adjusting for physical abuse, sociodemographics, and familial/psychosocial factors (girls: odds ratio [OR] = 1.99, 95% confidence interval [CI] = 1.51, 2.64; boys: OR = 4.88, 95% CI = 2.94, 8.10). Youth reporting physical abuse were also at increased risk for disordered eating after adjusting for sexual abuse, sociodemographics, and familial/psychosocial factors (girls: OR = 2. 00, 95% CI = 1.52, 2.62; boys: OR = 1.95, 95% CI = 1.26, 3.04). DISCUSSION: The findings suggest that strong familial relationships may decrease the risk for disordered eating among youth reporting abuse experiences, but both sexual and physical abuse are strong independent risk factors for disordered eating among both adolescent girls and boys.
OBJECTIVE: The purpose of this review is to evaluate the current state-of-the-science for interventions to increase bone mass gains in children and adolescents using weight-bearing physical activity or calcium supplementation. METHODS: Studies were located using computerized and manual searches of the empirical literature. Inclusion criteria were: (a) intervention study targeting weight-bearing physical activity or calcium intake; (b) inclusion of a control group; (c) subject age range under 18 years; and (d) outcome measured bone mineral density or bone mineral content. RESULTS: Weight-bearing physical activity and calcium supplement intervention studies both consistently show positive effects on bone mass gains in children and adolescents. The most consistent findings for both weight-bearing physical activity and calcium were for lumbar spine and total body bone sites. Only weight-bearing physical activity interventions had significant effects on the femoral neck sites. Low power may have contributed to the lack of statistically significant findings in several studies and also prevented proper evaluation of potential interactions between pubertal status and interventions on bone mass gains. CONCLUSIONS: Increases in weight-bearing physical activity or calcium intake have positive effects on bone mass gains in children and adolescents. Further research is needed to evaluate: (a) the long-term durability of these effects; (b) specific dose-response associations; (c) interactions between weight-bearing physical activity and calcium intake; and (d) interactions between pubertal development and weight-bearing physical activity or calcium intake on bone mass outcomes.
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OBJECTIVE: To describe health beliefs, weight concern, dieting practices, and weight-loss program preferences of American Indian women residing in an urban setting. DESIGN: Face-to-face interviews using a semistructured questionnaire were conducted and height and weight were measured. SUBJECTS/SETTING: Subjects were 203 American Indian adult women in an urban community setting. STATISTICAL ANALYSIS: Frequency distributions and chi 2 analysis were performed using the Statistical Analysis System software. RESULTS: About two-thirds of the subjects were overweight. Most women were concerned about obesity and reported attempting to manage their weight. Healthful weight-loss practices (e.g., eating more fruits and vegetables, increasing physical activity) were used most frequently. However, unhealthful practices, such as skipping meals/fasting, using laxatives/diuretics, and self-induced vomiting were also mentioned. Regular bingeing was reported by 10% of respondents. APPLICATIONS: Weight-management intervention efforts should focus on helping clients modify their diet and physical activity patterns. Low-cost programs offered in convenient locations would attract more participants, as would the provision of child care. Education about the dangers and ineffectiveness of unhealthful weight-loss practices will be necessary, given the high rates of such behaviors in this population.