Joachim Westenhoefer

Validation of the flexible and rigid control dimensions of dietary restraint

OBJECTIVE Two subscales for the Eating Inventory (Three-Factor Eating Questionnaire) are developed and validated: Rigid and Flexible control of eating behavior. METHOD Study I is an analysis of questionnaire data and a 7-day food diary of 54,517 participants in a computer-assisted weight reduction program. Study II is a study of 85 subjects used to develop a final item pool. Study III is a questionnaire survey of a random sample (N = 1,838) from the West German population aged 14 years and above used to validate the developed subscales. RESULTS Rigid control is associated with higher scores of Disinhibition, with higher body mass index (BMI), and more frequent and more severe binge eating episodes. Flexible control is associated with lower Disinhibition, lower BMI, less frequent and less severe binge eating episodes, lower self-reported energy intake, and a higher probability of successful weight reduction during the 1-year weight reduction program. DISCUSSION Rigid and flexible control represent distinct aspects of restraint having different relations to disturbed eating patterns and successful weight control.

Dietary restraint and disinhibition: Is restraint a homogeneous construct?

The homogeneity of the restraint construct is investigated in a study of 54,525 subjects participating in a weight reduction program. Using the German version of the TFEQ (Stunkard & Messick, 1985, Journal of Psychosomatic Research, 29, 71-83; Pudel & Westenhoefer 1989a, Fragebogen zum Essverhalten; Handanweisung), it is shown that different types of relations exist between the items measuring dietary restraint and the disinhibition scale. A discriminant analysis in a subgroup of moderately highly restrained eaters with either low or high disinhibition (n = 1759) reveals different sets of restraint behaviours and cognitions that differentiate between high and low disinhibition. These findings are replicated in an independent validation sample (n = 1693). Two restraint subscales are constructed, one associated with increasing disinhibition, the other with decreasing disinhibition. It is argued that different sets of restrained behaviours and cognitions should be differentiated when looking at the causal link between restraint and disturbances of eating behaviour.

Problems in identifying predictors and correlates of weight loss and maintenance: Implications for weight control therapies based on behaviour change

Weight management is a dynamic process, with a pre‐treatment phase, a treatment (including process) phase and post‐treatment maintenance, and where relapse is possible during both the treatment and maintenance.

Age and Gender Dependent Profile of Food Choice

Several studies have described remarkable differences in food choice between men and women. Consistently, women are reported to have higher intakes of fruit and vegetables, higher intakes of dietary fiber and lower intakes of fat. In accordance with such more healthy food choice, women usually attach greater importance to healthy eating. In addition, the motivation of weight control is more prominent in women and they are more likely to diet or restrain their eating behavior. Recently, studies found that health beliefs and weight control motivation may explain up to 50 percent of gender differences in food choice. In addition, less healthy food choice profiles of men may be related to their poorer nutritional knowledge. However, health beliefs, eating attitudes and dieting appear to be phenomena which vary throughout the life span. In growing older, changes in the chemosensory perceptual systems play an important role in food choice. The decline of gustatory and--perhaps even more pronounced--in olfactory function may lead to a decrease of the pleasantness of food, thus limiting the reinforcing properties of food intake which eventually results in a decrease of appetite, often reported in elderly people. In addition, there are some indications that sensory-specific satiety diminishes with age. Sensory-specific satiety is the reduction in the pleasantness of food as it is consumed. This decrease of pleasantness usually motivates the choice of other foods and therefore, a varied diet. Therefore, the decrease of sensory-specific satiety may in part explain the limited variety of the diet sometimes seen in elderly people. However, lifestyle, socio-economic situation and other variables may limit the influence of such physiological changes and help to maintain an adequate food intake despite these age-related processes.

Establishing Dietary Habits during Childhood for Long-Term Weight Control

Objective: To review psychosocial research with respect to relevance for the development of nutritional education strategies for optimal weight control during childhood and the longer term. Results: Recent decades have witnessed changes in the social context of eating, with a trend away from family meals towards grazing and eating alone. At the same time, the prevalence of overweight and obesity is increasing amongst both children and adults, with even young children deliberately practising weight control measures, ranging from selective food choice to self-induced vomiting. Such behaviour is motivated by unrealistic perceptions of healthy body weight and shape. Successful long-term management of healthy body weight is supported by flexible control of eating behaviour and long-term educational strategies. Children are interested in learning about a wide range of nutrition topics. However, to be effective, nutrition education should be appropriate to the stage of cognitive development according to the age of the child, and be placed in the context of the direct, perceivable and immediate benefits resulting from good nutrition. Conclusion: Educational strategies should focus on consumption of a balanced diet, coupled with provision of a variety of foods, including a range of nutrient-dense ‘healthy’ food and encouraging children to taste unfamiliar dishes. They should provide a stable and predictive pattern of social eating occasions to promote the social meaning and importance of eating, and to enable social learning of food preferences. Educational strategies should provide orientation and reassurance regarding the range of healthy and acceptable body weights and shapes. They should also encourage flexible control of eating behaviour to enable children to maintain their weight within this healthy range.

Behavioural correlates of successful weight reduction over 3 y. Results from the Lean Habits Study.

OBJECTIVE: To examine behavioural characteristics of subjects with successful long-term weight reduction.DESIGN: Prospective cohort study with 3 y follow-up.SETTING: Multicentre study of participants of a commercial weight-reduction programme (BCM-Programme).SUBJECTS: Until February 2000, 6857 voluntary study participants were included. Analyses are based on 1247 subjects with complete 3 y data.INTERVENTIONS: Open-group dietary and behavioural counselling with initial meal substitutions.RESULTS: Subjects show a number of significant behavioural improvements, for example, choice of low-fat food, flexible control of eating behaviour and coping with stress. Subjects who maintain these changes by the end of the first year have a higher probability of successful weight reduction after 3 y.CONCLUSIONS: Successful weight maintenance is associated with more pronounced improvements of health behaviours after 1 y. The likelihood of success increases with the number of behavioural patterns which are involved in the process of change.

Some restrictions on dietary restraint

Quantitative difference or qualitative change? ― Restrained eating and the disinhibition of control ― Is the concept of restraint too global?

Cognitive and weight-related correlates of flexible and rigid restrained eating behaviour.

OBJECTIVES Examine the association between components of restrained eating, cognitive performance and weight loss maintenance. METHODS 106 women, all members of a commercial slimming organisation for at least 6 months (mean±SD: 15.7±12.4 months), were studied who, having lost 10.1±9.7 kg of their initial weight, were hoping to sustain their weight loss during the 6 month study. Dietary restraint subcomponents flexible and rigid restraint, as well as preoccupying cognitions with food, body-shape and diet were assessed using questionnaires. Attentional bias to food and shape-related stimuli was measured using a modified Stroop test. Working memory performance was assessed using the N-back test. These factors, and participant weight, were measured twice at 6 month intervals. RESULTS Rigid restraint was associated with attentional bias to food and shape-related stimuli (r=0.43, p<0.001 resp. r=0.49, p<0.001) whereas flexible restraint correlated with impaired working memory (r=-0.25, p<0.05). In a multiple regression analyses, flexible restraint was associated with more weight lost and better weight loss maintenance, while rigid restraint was associated with less weight loss. CONCLUSIONS Rigid restraint correlates with a range of preoccupying cognitions and attentional bias to food and shape-related stimuli. Flexible restraint, despite the impaired working memory performance, predicts better long-term weight loss. Explicitly encouraging flexible restraint may be important in preventing and treating obesity.

Association of cognitive dietary restraint and disinhibition with prediabetes – cross-sectional and longitudinal data of a feasibility study in German employees

OBJECTIVE To investigate the impact of eating behaviour traits on central obesity, prediabetes and associated major dietary food patterns. DESIGN Assessment of eating behaviour was based on the revised German version of the Three-Eating Factor Questionnaire using cross-sectional and longitudinal data of a feasibility study in employees. Data on lifestyle and nutrition were obtained by validated self-administered questionnaires. Baseline characteristics were analysed by the univariate χ2 test or the Mann-Whitney test. To quantify correlations linear regression analysis was used. SETTING The Delay of Impaired Glucose Tolerance by a Healthy Lifestyle Trial (DELIGHT), which investigated measures to prevent type 2 diabetes mellitus in 2004-2008. SUBJECTS Employees (21-64 years, 127 men, 157 women) with elevated waist circumference (men ≥ 94 cm, women ≥ 80 cm) of five medium-sized companies in northern Germany. RESULTS At baseline (T0), BMI but particularly waist circumference showed a strong inverse correlation with flexible control (P < 0.0001) and a positive correlation with disinhibition (P < 0.0001) and rigid control (P = 0.063). Flexible control was also significantly inversely related to fasting plasma glucose (P = 0.040), energy intake (P < 0.0001), intake of meat and meat products (P = 0.0001), and positively associated with intake of fruit and vegetables (P < 0.0001) at baseline (T0). Changes in flexible control within the first year of intervention (T1 v. T0) predicted changes in central obesity (P < 0.0001) and fasting plasma glucose (P = 0.025). CONCLUSIONS DELIGHT shows that flexible control characterizes individuals with a higher dietary quality, a lower waist circumference and a lower glucose level. Enhancing flexible control more than rigid control, and decreasing disinhibition, seems beneficial in terms of central adiposity and glucose levels.

The Hyperactivity/Inattention Subscale of the Strengths and Difficulties Questionnaire Predicts Short- and Long-Term Weight Loss in Overweight Children and Adolescents Treated as Outpatients

Objective: The success of treatment for pediatric obesity is variable and often unsatisfactory. This study elucidates the influence of inattention and hyperactivity/impulsivity on short- and long-term weight loss and maintenance after outpatient treatment. Methods: We included 8- to 16-year-old overweight and obese participants treated in 17 multidisciplinary outpatient treatment centers in a nationwide observational study. All treatment centers that reported long-term (1-year) follow-up weight data of at least 60% of the participants were included. At the beginning and end of treatment and at 1 year follow-up weight and height were measured at the center. Inattention and hyperactivity/impulsivity were assessed with the hyperactivity/inattention subscale (HI) of the parent-rated Strengths and Difficulty Questionnaire (SDQ). General linear models were used with the standard deviation scores of the BMI (BMI-SDS) as dependent variable and HI scores as main independent variable adjusting for age, sex, baseline BMI-SDS, and center. Results: 394 participants were included (57% female, age: 11.7± 2.0 years, baseline BMI-SDS 2.32 ±.46 kg/m2). HI scores were significantly associated with short- and long-term BMI-SDS (p < 0.0005), with higher baseline HI scores predicting less weight loss. Conclusions: Our results indicate that inattention and hyperactivity/impulsivity are linearly associated with reduced short- and long-term weight loss. Implications for treatment are discussed.