Andrew J. Hill

Randomised controlled trial of primary school based intervention to reduce risk factors for obesity

Abstract Objective: To assess if a school based intervention was effective in reducing risk factors for obesity. Design: Group randomised controlled trial. Setting: 10 primary schools in Leeds. Participants: 634 children aged 7-11 years. Intervention: Teacher training, modification of school meals, and the development of school action plans targeting the curriculum, physical education, tuck shops, and playground activities. Main outcome measures: Body mass index, diet, physical activity, and psychological state. Results: Vegetable consumption by 24 hour recall was higher in children in the intervention group than the control group (weighted mean difference 0.3 portions/day, 95% confidence interval 0.2 to 0.4), representing a difference equivalent to 50% of baseline consumption. Fruit consumption was lower in obese children in the intervention group (−1.0, −1.8 to −0.2) than those in the control group. The three day diary showed higher consumption of high sugar foods (0.8, 0.1 to 1.6)) among overweight children in the intervention group than the control group. Sedentary behaviour was higher in overweight children in the intervention group (0.3, 0.0 to 0.7). Global self worth was higher in obese children in the intervention group (0.3, 0.3 to 0.6). There was no difference in body mass index, other psychological measures, or dieting behaviour between the groups. Focus groups indicated higher levels of self reported behaviour change, understanding, and knowledge among children who had received the intervention. Conclusion: Although it was successful in producing changes at school level, the programme had little effect on childrens behaviour other than a modest increase in consumption of vegetables. What is already known on this topic Obesity is increasing among school children and demands preventive strategies Randomised controlled trials of school based primary prevention programmes have all used a prescriptive approach What this study adds Behavioural changes were disappointing with this programme based on the health promoting schools philosophy, despite changes at school level The only positive outcome was a modest increase in vegetable consumption The discrepancy between changes achieved at the individual and school level raises issues regarding the problems inherent in such trials

Self-esteem and quality of life in obese children and adolescents: A systematic review

Although an increasing number of children and adolescents are becoming obese, the psychological morbidities associated with obesity are not well established. Existing reviews report modest associations between obesity and global self-esteem. However, none have examined how this affects multi-component assessments of self-esteem and quality of life in young people with defined obesity. A literature search identified 17 self-esteem and 25 quality of life studies of cross-sectional, longitudinal or intervention design published since 1994. Child-completed and parent-proxy assessments were consistent in showing significant reductions in global self-esteem and quality of life in obese youth. Competences particularly affected were physical competence, appearance and social functioning. There were no clear differences in effects between children and adolescents, and evidence on gender and ethnicity was lacking. Competency improvements occurred in the presence and absence of weight loss, suggesting their value as intervention outcomes and the need for further investigation.

Food craving, dietary restraint and mood

A common assumption is that dieting causes food cravings, probably as a result of food energy deprivation. This issue was investigated in a two-phase study. In phase one, 206 women completed the Dutch Eating Behaviour Questionnaire, the Three-Factor Eating Questionnaire and a food craving scale. A correlational analysis showed food craving to be only weakly related to dietary restraint, but highly and significantly correlated with external eating, emotional eating and susceptibility to hunger. In phase two, ten women who regularly experienced food cravings and ten who rarely craved food kept prospective records of their food intake, daily mood and food craving episodes. There were few differences in eating behaviour, although the cravers tended to consume slightly more daily energy than the non-cravers. The cravers had higher ratings of boredom and anxiety during the day, and dysphoric mood was prominent prior to the cravings themselves. Food deprivation does not appear to be a necessary condition for food cravings to occur. Rather, food cravings are closely associated with mood, in particular as an antecedent to craving and also as a consequence of craving.

The effectiveness of web-based interventions designed to decrease alcohol consumption – a systematic review

OBJECTIVE To review the published literature on the effectiveness of web-based interventions designed to decrease consumption of alcohol and/or prevent alcohol abuse. METHOD Relevant articles published up to, and including, May 2006 were identified through electronic searches of Medline, PsycInfo, Embase, Cochrane Library, ASSIA, Web of Science and Science Direct. Reference lists of all articles identified for inclusion were checked for articles of relevance. An article was included if its stated or implied purpose was to evaluate a web-based intervention designed to decrease consumption of alcohol and/or to prevent alcohol abuse. Studies were reliably selected and quality-assessed, and data were independently extracted and interpreted by two authors. RESULTS Initial searches identified 191 articles of which 10 were eligible for inclusion. Of these, five provided a process evaluation only, with the remaining five providing some pre- to post-intervention measure of effectiveness. In general the percentage quality criteria met was relatively low and only one of the 10 articles selected was a randomized control trial. CONCLUSION The current review provides inconsistent evidence on the effectiveness of eIectronic screening and brief intervention (eSBI) for alcohol use. Process research suggests that web-based interventions are generally well received. However further controlled trials are needed to fully investigate their efficacy, to determine which elements are keys to outcome and to understand if different elements are required in order to engage low- and high-risk drinkers.

Breakdown of dietary restraint following mere exposure to food stimuli: interrelationships between restraint, hunger, salivation and food intake

It was hypothesised that the hunger-enhancing effects of exposure to the sight and smell of palatable food would disinhibit eating in restrained eaters (self-reported dieters). In two experiments exposure to palatable food stimuli led to increases in motivational (hunger) ratings and salivation, and was followed by overeating in restrained subjects compared with the control condition (no food during exposure) and a condition in which nonpreferred food was presented during the exposure phase. The food intake of unrestrained subjects, on the other hand, was reduced following exposure to palatable food in the first experiment. This shows that breakdown of dietary restraint can be induced by food stimuli even when the food does not constitute a preload. Mere exposure to the sight and smell of palatable food is sufficient to precipitate loss of dieting motivation. The effects of exposure on hunger and salivation were, in general, unrelated to food intake or degree of dietary restraint. Therefore, changes in hunger do not appear to directly mediate increased food intake in dieters. Instead, it is tentatively suggested that anxiety resulting from exposure to liked food may play a role both in disinhibiting eating and suppressing salivation in restrained subjects.

Obesity and Risk of Low Self-esteem: A Statewide Survey of Australian Children.

OBJECTIVE. There is variation in the psychological distress associated with child obesity. Low self-esteem, when observed, provides very little information about the nature of the distress and no indication of the proportion of obese children affected. This study used a domain approach to self-competence to evaluate self-esteem in a representative sample of Australian children. PARTICIPANTS AND METHODS. A total of 2813 children (mean age: 11.3 years) took part in the study. They were recruited from 55 schools and were all in the last 2 years of primary school. Participants completed the Self-perception Profile for Children, a measure of body shape perception, and their height and weight were measured. RESULTS. Obese children had significantly lower perceived athletic competence, physical appearance, and global self-worth than their normal weight peers. Obese girls scored lower in these domains than obese boys and also had reduced perceived social acceptance. Obese children were 2–4 times more likely than their normal weight peers to have low domain competence. In terms of prevalence, 1 of 3 obese boys and 2 of 3 obese girls had low appearance competence, and 10% and 20%, respectively, had low global self-worth. Body dissatisfaction mediated most of the association between BMI and low competence in boys but not in girls. CONCLUSIONS. Obesity impacts the self-perception of children entering adolescence, especially in girls, but in selected areas of competence. Obese children are at particular risk of low perceived competence in sports, physical appearance, and peer engagement. Not all obese children are affected, although the reasons for their resilience are unclear. Quantifying risk of psychological distress alongside biomedical risk should help in arguing for more resources in child obesity treatment.

Uncoupling sweet taste and calories: Comparison of the effects of glucose and three intense sweeteners on hunger and food intake

This study was carried out to disclose effects generated by the uncoupling of the sensory and energetic components of sweet solutions. A comparison was made between equi-sweet preloads of three intense sweeteners (saccharin, aspartame and acesulfame-K), a bulk sweetener (glucose) and a nonsweet water control. Measures were made of subjective ratings of motivation to eat, food preferences and energy intake in a test meal. The glucose load produced a consistent pattern of changes on all measures. The intense sweeteners tended to facilitate motivational ratings and food preference checklist responses, but marginally lowered intake in the test meal. The facilitative action is probably due to the stimulation of sensory receptors for sweetness by the high-intensity agents, while the effects on intake are most likely due to a ceiling effect imposed by methodological limitations of this particular design. The results of this study must be interpreted with reference to the prevailing experimental conditions, but they suggest that intense sweeteners can produce significant changes in appetite. Of the intense sweeteners, aspartame gave rise to the most pronounced effects.

Food advertising on British children's television : a content analysis and experimental study with nine-year olds

OBJECTIVES: The nature and significance of food advertising during children’s television was examined in two studies: a content analysis of advertising (Study 1) and an investigation of the impact of food adverts on the self-perception of overweight children (Study 2).PARTICIPANTS: Study 1 monitored 91 h of children’s broadcasting on four terrestrial and satellite stations in the UK. In Study 2, 103 children aged 9.75 y viewed two videotaped cartoons containing either food or non-food product advertisements.MEASURES: Study 1 used a detailed record of advertisement style and content. Study 2 included a self-report measure of current state, and measures of self-esteem, dietary restraint, body weight and height.RESULTS: Half of the 828 adverts were for food products, 60% of which were for breakfast cereals and confectionery/snacks. Food advertisements used significantly more animation, stories, humour and the promotion of fun/happiness/mood alteration. In Study 2, significant interactions between advertisement type and overweight were observed on ratings of perceived health and appetite for sweets.CONCLUSION: While small changes are apparent, advertisements during children’s television are still dominated by those for foods of questionable nutritional value, in a manner designed to engage attention and emotional response. That overweight children appeared more influenced by their personal enhancement message, suggests the value of further work identifying who is most influenced and by what features of advertising.

The experience of food craving: A prospective investigation in healthy women

This study aimed to provide a detailed analysis of the experience of food craving in a healthy, non-clinical group of women. Twenty-five women who reported food cravings prospectively recorded their experiences over a period of 5 weeks using a Food Craving Record. The average number of cravings recorded was just under 2 per week. Craving for chocolate amounted to 49% of all the food cravings. Subtle differences in the change in arousal and hunger were noted between chocolate cravings and those for other sweet foods. Additional differences were found between these cravings and those for savoury foods, in their situational circumstances and speed of disappearance. There was a premenstrual increase in food cravings but no selective change in the types of food craved. Overall, the food cravings reported by these women were hunger-reducing, mood-improving experiences, directed at wanting to consume highly pleasant tasting food. This analysis should serve as a template against which other subject groups and other forms of craving may be explored.

Bulimics' responses to food cravings: is binge-eating a product of hunger or emotional state?

This study examined the roles of hunger, food craving and mood in the binge-eating episodes of bulimic patients, and identified the critical factors involved in the processes surrounding binge-eating episodes that follow cravings. This was a prospective study of the binge-eating behaviour of 15 women with bulimia nervosa. The participants used food intake diaries and Craving Records to self-monitor their nutritional behaviour, hunger levels and affective state. Cravings leading to a binge were associated with higher tension, lower mood and lower hunger than those cravings not leading to a binge. Levels of tension and hunger were the critical discriminating variables. The findings of the study support empirical evidence and models of emotional blocking in binge-eating behaviour and challenge the current cognitive starve-binge models of bulimia. The role of food cravings in the emotional blocking model is discussed in terms of a classically conditioned motivational state. Implications for treatment are addressed.