International journal of obesity and related metabolic disorders : journal of the International Association for the Study of Obesity最新文献

Objective: Longitudinal survey data from a number of countries confirm that the number of overweight children continues to increase at alarming rates, and even developing countries are experiencing a rise in their overweight population. There is ample consensus that prevention strategies are essential to turn the tide of the obesity epidemic, and yet there are still relatively few proven prevention approaches for children. This paper briefly discusses some of the common features of childhood obesity prevention programs, focusing on the experience in the US and Canada.

Approach: Most prevention programs include at least one of the following components: dietary changes, physical activity, behavior and social modifications, and family participation. School-based prevention programs may also include elements related to the school environment and personnel. Primary prevention programs cannot usually restrict caloric intake, but may effectively reduce the energy intake by reducing the energy density of foods, increasing offering of fresh fruits and vegetables, using low-calorie versions of products, and reducing offering of energy-dense food items. Physical activity interventions have recently focused more on reducing inactive time, particularly television viewing. Results from recent studies have reported success in reducing excess weight gain in preadolescents by restricting TV viewing.

Summary: Integrating all the activities of a multi-component prevention intervention, and delivering and sustaining it in different environments, continues to be a major challenge for health professionals as well as for parents, educators, and children themselves. Still, encouraging progress has been made in several areas, and the increased awareness of the problem of childhood obesity by all concerned will continue to foster our efforts in this area.

Objective: To assess the role of television as tool for childhood obesity prevention.

Method: Review of the available literature about the relationship between television and childhood obesity, eating habits and body shape perception.

Results: The reviewed studies showed the following: television watching replaces more vigorous activities; there is a positive correlation between time spent watching television and being overweight or obese on populations of different age; obesity prevalence has increased as well as the number of hours that TV networks dedicate to children; during the last 30 y, the rate of children watching television for more than 4 h per day seems to have increased; children are exposed to a large number of important unhealthy stimulations in terms of food intake when watching television; over the last few years, the number of television food commercials targeting children have increased especially when it comes to junk food in all of its forms; the present use of food in movies, shows and cartoons may lead to a misconception of the notion of healthy nutrition and stimulate an excessive intake of poor nutritional food; and obese subjects shown in television programmes are in a much lower percentage than in real life and are depicted as being unattractive, unsuccessful and ridiculous or with other negative traits and this is likely to result in a worsening of the isolation in which obese subjects are often forced. The different European countries have different TV legislations.

Conclusion: The usual depiction of food and obesity in television has many documented negative consequences on food habits and patterns. The different national regulations on programs and advertising directed to children could have a role in the different prevalence of childhood obesity in different European countries. Television could be a convenient tool to spread correct information on good nutrition and obesity prevention.

Objective: To review concepts and propose measures related to the use of anthropometry for early identification of excessive weight gain in children.

Methods: Review of results from national and international studies focusing on the assessment of childhood growth, and evaluation of the weight-for-height z-scores of individual children using the 1977 National Center for Health Statistics and the 2000 Centers for Disease Control and Prevention growth charts.

Results: At present, few countries (23%) use indicators based on weight and height measurements to classify child body weight status. Less than one-third of growth monitoring programmes assess the growth of children beyond 6 y of age. Growth charts based on descriptive samples of populations undergoing increasing trends of childhood overweight and obesity result in substantial underestimation of true rates of these conditions.

Conclusion: Early recognition of excessive weight gain relative to linear growth should become standard clinical practice by the following: (a) the routine collection of height measurements to enable monitoring weight-for-height and body mass index (BMI); (b) the expansion of existing monitoring programmes to include the assessment of all children up to 18 y at least once a year; (c) the interpretation of weight-for-height and BMI indices based on prescriptive reference data; and (d) the early intervention after an increase in weight-for-height or BMI percentiles has been observed.

Objective: To review the role of genes and lifestyle factors, particularly dietary habits and physical activity patterns, in obesity risk as well as their potential interactions.

Design and measurements: A descriptive report of a number of genes definitely ascribed or potentially implicated in excessive fat accumulation leading to obesity as assessed by different research approaches (Mendelian transmission, genetic animal models, epidemiological association/linkage studies and genome-wide scans). Also, the involvement of macronutrient intake and composition (fat/carbohydrate) as well as the role of activity-linked energy expenditure in obesity onset is reviewed.

Results: Examples of the role of the genotype as well as of the dietary macronutrient composition/intake and sedentary/low energy cost of physical activities in obesity prevalence are reported.

Conclusions: Both genes and everyday life environmental factors such as cultural and social mediated food intake and reduced domestic and living work activities are involved in the obesity pandemia. The occurrence of gene x gene and gene x environmental factors interactions makes it more difficult to interpret the specific roles of genetics and lifestyle in obesity risk.

Objective: This paper explores the major changes in diet and physical activity patterns around the world and focuses on shifts in obesity.

Design: Review of results focusing on large-scale surveys and nationally representative studies of diet, activity, and obesity among adults and children.

Subjects: Youth and adults from a range of countries around the world.

Measurements: The International Obesity Task Force guidelines for defining overweight and obesity are used for youth and the body mass index > or =25 kg/m(2) and 30 cutoffs are used, respectively, for adults.

Results: The nutrition transition patterns are examined from the time period termed the receding famine pattern to one dominated by nutrition-related noncommunicable diseases (NR-NCDs). The speed of dietary and activity pattern shifts is great, particularly in the developing world, resulting in major shifts in obesity on a worldwide basis. Data limitations force us to examine data on obesity trends in adults to provide a broader sense of changes in obesity over time, and then to examine the relatively fewer studies on youth. Specifically, this work provides a sense of change both in the United States, Europe, and the lower- and middle-income countries of Asia, Africa, the Middle East, and Latin America.

Conclusion: The paper shows that changes are occurring at great speed and at earlier stages of the economic and social development of each country. The burden of obesity is shifting towards the poor.

Objective: To evaluate the 6-month impact of a physical activity (PA) multilevel intervention on activity patterns and psychological predictors of PA among adolescents. The intervention was directed at changing knowledge and attitudes and at providing social support and environmental conditions that encourage PA of adolescents inside and outside school.

Subjects and design: Randomised, controlled ongoing field trial (ICAPS) in middle-school's first-level adolescents from eight schools selected in the department of the Bas-Rhin (Eastern France) with a cohort of 954 adolescents (92% of the eligible students) initially aged 11.7+/-0.6 y. The 6-month changes in participation in leisure organised PA (LOPA), high sedentary (SED) behaviour (>3 h/day), self-efficacy (SELF) and intention (INTENT) towards PA were analysed after controlling for baseline measures and different covariables (age, overweight, socioprofessional occupation), taking into account the cluster randomisation design.

Results: The proportion of intervention adolescents not engaged in organised PA was reduced by 50% whereas it was unchanged among control students. After adjustment for baseline covariables, LOPA participation significantly increased among the intervention adolescents (odds ratio (95% confidence interval) (OR)=3.38 (1.42-8.05) in girls; 1.73 (1.12-2.66) in boys), while high SED was reduced (OR=0.54 (0.38-0.77) in girls; 0.52 (0.35-0.76) in boys). The intervention improved SELF in girls, whatever their baseline LOPA (P<10(-4)) and INTENT in girls with no baseline LOPA (P=0.04). SELF tended to improve in boys with no baseline LOPA, without reaching statistical significance. When included in the regression, follow-up LOPA was associated with improvement of SELF in girls (P=0.02) and of INTENT in girls with no baseline PA (P<0.02). The intervention effect was then attenuated.

Conclusion: After 6 months of intervention, ICAPS was associated with a significant improvement of activity patterns and psychological predictors, indicating a promising approach for modifying the long-term PA level of adolescents.

Background: Excessive obesity in children and adolescents is increasing in western countries all over the world. Treatment of those young subjects is extremely difficult. In cases who do not respond in any regard to conservative treatment regimens, it is worthwhile to also offer bariatric surgical procedures.

Methods: In eight young subjects with a mean age of 16.0+/-1.3 y, mean BMI 49.1+/-5.2 who where totally resistant against different therapeutic regimens, we performed adjustable laparoscopic banding surgery. Psychological tests were carried out to find out if there were any psychological disturbances. In all patients, the depression inventory for adolescents (DIKJ) and clinical interviews were carried out.

Results: No complications were seen; mean follow-up of 10.5+/-6.0 months showed a weight loss of 25+/-6.5 kg. All adolescents felt for the first time that it was possible to lose weight and were very happy about their body attitude. They were able to adhere to a strict dietary regimen, which allowed them to eat without any hunger problems. It was observed that most of these patients have depressive symptoms and a very low self-esteem. Some patients suffer from nervous anxiety, poor peer acceptance, less athletic competence or forms of victimisation too.

Conclusions: From these results, we conclude that laparoscopic gastric banding surgery seems to be a method that could be offered to morbidly obese adolescents. However, long-term follow-up is essential and psychological problems should be carefully studied.

Background: There is evidence that malnutrition in early life induces a growth retardation leading, in adult life, to manifest components of the metabolic syndrome. However, the impact on obesity seems less clearly established.

Objective: To review the effects of foetal and postnatal malnutrition on the programming of obesity in the context of the metabolic syndrome, as well as the link between central obesity and cardiovascular diseases.

Methods: Included in the review were recent papers exploring the mechanisms linking maternal nutrition with impaired foetal growth and later obesity, cardiovascular disease, hypertension and diabetes in humans and animals.

Results: The programming of obesity during foetal and early postnatal life depends of the timing of maternal malnutrition as well as the postnatal environment. Obesity arises principally in offspring submitted to malnutrition during early stages of gestation and which presented early catch-up growth. The programming may involve the dysregulation of appetite control or the hormonal environment leading to a context favourable to obesity development (hypersecretion of corticosteroids, hyperinsulinaemia and hyperleptinaemia and anomalies in the IGF axis). Adipose tissue secretes actively several factors implicated in inflammation, blood pressure, coagulation and fibrinolysis. The programmed development of intra-abdominal obesity after early growth restriction may thus favour higher prevalence of hypertension and cardiovascular diseases.

Conclusions: Abdominal obesity appears in malnourished offspring and is aggravated by early catch-up growth. Higher rates of intra-abdominal obesity observed after growth restriction may participate to hypertension and create atherothrombotic conditions leading to the development of cardiovascular diseases.

Objective: Obesity in children impacts on their health in both the short and long term. Having an accurate and precise body composition assessment, it may be possible to control growth process and predict adult status in order to reduce the risk factors for various diseases.

Method: To review methods for body composition assessment that may provide new insights into the clinical practicality of paediatric obesity prevention/treatment. To present which specific outcome measurements in paediatric obesity prevention trials could be used to detect subjects at risk as early as possible.

Results: We discussed body composition measurements that could be used in daily clinical practice and as outcome measurements in prevention trials.

Conclusion: These measurement procedures could be associated with methods for preventing obesity onset or retarding the weight gain associated with ageing.

Objective: For a decade or more, poor nutrition during gestation, expressed as low weight at birth, was held to be the factor responsible for insulin resistance later in life. Birth weights, however, are rising and insulin-resistant states, such as diabetes, faster still. Alternative explanations are needed for insulin resistance in contemporary society. This review cites data from the EarlyBird study on the relationships of insulin resistance and metabolic disturbance in early childhood.

Design: EarlyBird is a nonintervention prospective cohort study that asks the question 'Which children develop insulin resistance, and why?' It is unique in taking serial blood samples from a young age with which to monitor the behaviour of insulin resistance and its metabolic correlates, and in its comprehensive assessment of factors known or thought to influence insulin resistance

Subjects: In all, 307 randomly selected healthy school children at school entry (mean age 4.9 y) and at 12 and 24 months later.

Measurements: In the children: Birth weight and, at each time point height, weight, body mass index (BMI, kg/m(2)), skinfolds at five sites, circumferences, resting energy expenditure, physical activity, body composition, heart rate variability, diet, HOMA-IR and HOMA-ISC, blood pressure, full blood count, haemoglobin and haematocrit, HbA1C, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, uric acid, IGF-1, gonadotrophins and SHBG. In their parents: At baseline height, weight, BMI, waist circumference, HOMA-IR and HOMA-ISC, full blood count, haematocrit, HbA1C, total cholesterol, HDL cholesterol, calculated LDL cholesterol, triglycerides, uric acid, gonadotrophins and SHBG.

Results: Four observations are reported here: (1) There are clear correlations in contemporary children between insulin resistance and weight at 5 y, but none with birth weight. (2) Females throughout life are intrinsically more insulin resistant than males. (3) The substantial variation of physical activity among young children is attributable to the child, and not to his environment. (4) There is dissociation in young children between fatness and insulin resistance.

Conclusion: There is much yet to be learned about the development of obesity and insulin resistance in children. The notions of overnutrition and underactivity alone are too simplistic.