Influence of cognitive eating restraint on total-body measurements of bone mineral density and bone mineral content in premenopausal women aged 18-45 y: a cross-sectional study

BACKGROUND: We examined the relation between cognitive eating restraint (CER) and total-body measurements of bone mineral density (BMD) and bone mineral content (BMC). OBJECTIVE: Our objective was to determine whether women with CER had lower total-body BMD and BMC than did other women. DESIGN: Premenopausal women, 90-150% of ideal weight, had measurements of their BMD and BMC made and completed questionnaires on physical activity, weight history, body size satisfaction, dieting history, eating behavior, and childbearing history. Bone measurements were examined for differences between groups with low and high CER scores by using analysis of covariance and quartiles of body weight to adjust for body size differences. CER was assessed by using the Three-Factor Eating Inventory and was defined as a score > or =9; normal eating restraint (NER) was defined by a score <9. Total-body BMC, BMD, and fat and lean masses were measured by dual-energy X-ray absorptiometry. RESULTS: Fifty-two percent of the women were classified as having CER. Women with CER were significantly more dissatisfied with their bodies. Analysis of covariance, with weight as the covariate, indicated a significant difference in BMC between women in preplanned pairs from the 5 lowest and 5 highest CER levels. No significant differences in BMD were observed between groups. Significantly lower BMC was found in women with high CER scores and body weights <71 kg than in those with high CER scores and weights > or =71 kg. CONCLUSIONS: BMC was significantly differently between women with low and high CER scores. BMC was significantly lower in women with body weights <71 kg and classified with CER. Lower BMC in women with high CER scores may indicate an increased risk of osteoporosis.     

Dietary restraint and gestational weight gain

OBJECTIVE: To determine whether a history of preconceptional dieting and restrained eating was related to higher weight gains in pregnancy. DESIGN: Dieting practices were assessed among a prospective cohort of pregnant women using the Revised Restraint Scale. Women were classified on three separate subscales as restrained eaters, dieters, and weight cyclers. SUBJECTS: Participants included 1,223 women in the Pregnancy, Infection, and Nutrition Study. MAIN OUTCOME MEASURES: Total gestational weight gain and adequacy of weight gain (ratio of observed/expected weight gain based on Institute of Medicine recommendations). STATISTICAL ANALYSES PERFORMED: Multiple linear regression was used to model the two weight-gain outcomes, while controlling for potential confounders including physical activity and weight-gain attitudes. RESULTS: There was a positive association between each subscale and total weight gain, as well as adequacy of weight gain. Women classified as cyclers gained an average of 2 kg more than noncyclers and showed higher observed/expected ratios by 0.2 units. Among restrained eaters and dieters, there was a differential effect by body mass index. With the exception of underweight women, all other weight status women with a history of dieting or restrained eating gained more weight during pregnancy and had higher adequacy of weight gain ratios. In contrast, underweight women with a history of restrained eating behaviors gained less weight compared to underweight women without those behaviors. CONCLUSIONS: Restrained eating behaviors were associated with weight gains above the Institute of Medicine's recommendations for normal, overweight, and obese women, and weight gains below the recommendations for underweight women. Excessive gestational weight gain is of concern because of its association with postpartum weight retention. The dietary restraint tool is useful for identifying women who would benefit from nutritional counseling prior to or during pregnancy with regard to achieving targeted weight-gain recommendations.     

“Restrained Eating” vs “Trying to Lose Weight”: How Are They Associated with Body Weight and Tendency to Overeat among Postmenopausal Women?

In an effort to control body weight, many women diet or adopt a restrained approach to eating. Although common, dieting and dietary restraint remain poorly understood. Clarification of their association with health-related factors, such as body weight and overeating, is required. In this study, we explored how dieting and dietary restraint were associated with body mass index (BMI; calculated as kg/m²) and disinhibition (tendency to overeat) in a sample of 1,071 postmenopausal women aged 45 to 75 years. In a survey of dietary attitudes and body image, we asked about current dieting status and measured restrained eating and disinhibition. Self-reported height and weight were used to calculate BMI, which was confirmed in a subset. Participants were classified by dieting status (yes/no) and level of dietary restraint (high/low by median split).We examined the independent effects of dieting and restrained eating on BMI and disinhibition. More than half of the sample (53%) reported current dieting. Dieting and dietary restraint showed opposite associations with BMI. Among dieters, BMI was 4.1 higher (95% confidence interval: 3.6 to 4.6) than among nondieters. In contrast, BMI of restrained eaters was 1.0 lower (95% confidence interval: −1.6 to −0.5) than unrestrained eaters. Dieters had higher scores for disinhibition, but disinhibition scores of restrained eaters did not differ from those of unrestrained eaters. Our results suggest that dieting and dietary restraint are not equivalent. Finding that dietary restraint is associated with lower BMI (when considered independently of dieting) suggests that restrained eating, rather than dieting, may contribute to successful weight management.     

Bone Health in Immigrant Hispanic Women Living in Texas

Osteoporosis is a serious national public health problem, and is expected to increase significantly over the next few decades, especially in women. A limitation of bone health research exists since few studies have involved Hispanic women, and even fewer, Hispanic immigrant women. For this study we examined the effects of anthropometric, behavioral, and health history variables on bone mineral density (BMD) in 84 immigrant Hispanic women, age 40 and above. BMD was assessed at the spine, femur, and forearm using dual energy x-ray absorptiometry (DXA). Demographic information, health histories, and behavioral risk factors were obtained from a questionnaire. In the younger group (mean age = 44.1 years) 61% had spinal osteopenia, and in the postmenopausal group (mean age = 53.0 years) 59% had osteopenia and 13% had osteoporosis. Femur sites were free of osteoporosis. Mean body mass index (BMI) was 31.8 ± 6.1 and mean waist girth was 95.6 ± 12.5 cm, indicating overall and abdominal obesity. Partial correlations indicated a significant positive relationship between body fat variables and total femur BMD values. ANOVAs revealed no differences in BMD values at any bone site across tertile levels for calcium intake or for physical activity. However, supplemental and dietary calcium intakes were very low and few participants engaged in regular physical activity outside of work and activities of daily living (ADL). In light of the expected increase in osteoporosis in this population and the prevalence of spinal osteopenia in the younger participants, education about the health risks of osteoporosis should be made available to this group.     

Effect of weight change on bone mass in female adolescents

The purpose of this study was to examine changes in bone mineral density/bone mineral content (BMD/BMC) in obese female adolescents (Tanner stages 2 to 4) pursuing a weight reduction program. This was a prospective pilot clinical investigation involving 92 obese females screened to meet inclusion criteria and required to participate in a 6-month weight loss intervention. Baseline, 6 months, and 12 months measurements were taken for total body/lumbar spine BMD/BMC and percentage body fat. Survey instrumentation included the following: calcium food frequency/24-hour dietary recall, physical activity, and psychological assessments for anxiety/self-esteem. Changes in bone measurements were compared with changes in body weight measurements using multiple linear regression. Other potentially confounding variables analyzed included bone area, calcium intake, baseline Tanner stage, activity level, and height. Total body/lumbar spine BMD/BMC changes were found to be most significantly correlated with weight changes in the subject population. Although mean weight increased, the rate of increase per a given height velocity slowed to an appropriate height for weight ratio. Individuals who lost weight did not lose BMD/BMC; however, the rate of growth declined when compared with all study subjects whose bone growth rate was consistent with normal weight female adolescents. In this study, weight changes were strongly related to bone measurement changes in an obese adolescent female population. Dietitians counseling obese young girls are encouraged to emphasize the importance of a healthy weight loss program with optimal calcium intake and inclusive of weight-bearing exercises.     

膳食钙、磷以及奶制品对绝经后妇女骨密度的影响

目的探讨膳食中钙、磷以及奶制品的摄入量对骨密度及骨盐含量的影响,为研究骨质疏松的预防提供相关线索和依据。方法在广州市越秀区农林街社区发放传单招募调查对象,并采用自编的结构化标准问卷,对320名广州绝经后妇女的膳食习惯进行调查,并测量其全身、股骨全身、股骨颈、股骨干、大粗隆、Ward’s三角以及腰锥1～4的骨密度和骨量,采用多因素逐步回归分析探讨膳食钙、磷及奶制品对骨盐含量及骨密度的影响。结果 320名调查对象平均57.1岁,平均绝经年限7.3年,平均每天摄入钙、磷及奶制品分别为822 mg、949 mg和126 g,平均全身骨密度为1.054 g/cm2,磷与7个部位的骨密度及骨盐含量呈正相关关系（P〈0.05）。随着磷摄入量增加,全身及腰锥1～4骨密度增加,偏回归系数值分别为0.121和0.184 g.（cm2）-1.g-1.d-1。随着奶制品摄入量增加,股骨全身、股骨干骨密度也相应增加,骨密度偏回归系数值分别为0.686、0.841mg.（cm2）-1.g-1.d-1。钙与全身、股骨全身、股骨颈、大粗隆、股骨干和Ward’s三角的BMC具有正相关性,而在钙与BMD关系中,钙只与股骨全身、大粗隆和股骨干呈正相关性,且每日膳食中每增加100 g钙的摄入量,则股骨全身、大粗隆、股骨干的骨密度相应增加5.3、4.8和7.6 g/cm2。结论增加膳食中钙、磷以及奶制品的摄入量有利于绝经后妇女的骨盐含量及骨密度的提高。     

Restrained eating behavior and the metabolic response to dietary energy restriction in women

OBJECTIVE: To determine whether prior eating behavior characterized by dietary restraint alters responses in energy expenditure and substrate oxidation associated with a short-term, energy-restricted diet. RESEARCH METHODS AND PROCEDURES: A repeated-measures, 3-day diet-intervention study of adequate (125 kJ/kg of body weight) or restricted (62.5 kJ/kg) energy intake was conducted with 30 women, 20 to 46 years, BMI 25 to 45 kg/m(2), whose prior eating behavior was "restrained" or "unrestrained." The Eating Inventory (cognitive restraint subscale) was used to measure restrained eating behavior. Energy expenditure and substrate oxidation were measured after a 12-hour fast and during the first and fourth hours after a standard meal. Plasma glucose, nonesterified fatty acids, and insulin were measured at corresponding times. Body composition was determined by total body electrical conductivity. RESULTS: Resting energy expenditure was not affected by 3 days of energy restriction. Short-term energy restriction resulted in lower respiratory-exchange ratios, higher rates of fat oxidation, and lower rates of carbohydrate oxidation. Subjects classified as restrained eaters had higher postprandial respiratory-exchange ratios and carbohydrate-oxidation rates compared with unrestrained eaters. Fasting insulin concentrations were lower in restrained eaters. These effects associated with prior eating behavior were independent of the diet intervention. DISCUSSION: Metabolic outcomes associated with a 3-day energy-restricted diet (i.e., increased fat oxidation and decreased carbohydrate oxidation) were not affected by prior restrained eating behavior. However, restrained eating behavior was associated with increased carbohydrate oxidation after a mixed meal. This effect of restrained eating behavior may be attributable to increased insulin sensitivity.     

Sodium and calcium intakes and bone mass in rats revisited

OBJECTIVE: High sodium intake accompanied by insufficient dietary calcium may have detrimental effects on bone mass. Our study evaluated the effects of increased sodium and decreased calcium intakes on bone mineral density (BMD) and bone mineral content (BMC) in rats. METHODS: Four-month-old female Wistar rats were given deionized water or 1.8% solution of sodium chloride in deionized water and fed normal (1.2%) or marginal (0.33%) calcium in the diet for 2 mo. At the end of the experiment, BMD and BMC of the whole body and urinary sodium and calcium excretion were evaluated. All rats were killed and right femurs were removed to assess dry and ash weights. Two-way analysis of variance was used to evaluate effect of salt intake and effect of dietary calcium on these parameters. RESULTS: Salt-loaded animals had greater water consumption during the entire 2-mo period and significantly lower body weight from week 5 of the experiment. High salt intake increased urine volume and urinary excretion of sodium and calcium. Urinary calcium was about five times higher in salt-loaded animals than in rats on deionized water irrespective of dietary calcium content. Calcium in diet itself had no significant effect on these parameters. High salt intake slightly, but not significantly, decreased BMD, BMC, and femur weights. Lower calcium in diet significantly decreased BMD, and its effect on femur ash weight almost reached a level of significance. CONCLUSION: We confirmed the benefit of adequate calcium intake to BMD. Under our experimental condition, high salt intake in rats for 2 mo had no statistically significant effect on femur weights, BMD, or BMC even with marginal calcium in the diet.     

Focusing on media body ideal images triggers food intake among restrained eaters: A test of restraint theory and the elaboration likelihood model

Although research consistently shows that images of thin women in the media (media body ideals) affect women negatively (e.g., increased weight dissatisfaction and food intake), this effect is less clear among restrained eaters. The majority of experiments demonstrate that restrained eaters – identified with the Restraint Scale – consume more food than do other participants after viewing media body ideal images; whereas a minority of experiments suggest that such images trigger restrained eaters' dietary restraint. Weight satisfaction and mood results are just as variable. One reason for these inconsistent results might be that different methods of image exposure (e.g., slideshow vs. film) afford varying levels of attention. Therefore, we manipulated attention levels and measured participants' weight satisfaction and food intake. We based our hypotheses on the elaboration likelihood model and on restraint theory. We hypothesised that advertent (i.e., processing the images via central routes of persuasion) and inadvertent (i.e., processing the images via peripheral routes of persuasion) exposure would trigger differing degrees of weight dissatisfaction and dietary disinhibition among restrained eaters (cf. restraint theory). Participants (N = 174) were assigned to one of four conditions: advertent or inadvertent exposure to media or control images. The dependent variables were measured in a supposedly unrelated study. Although restrained eaters' weight satisfaction was not significantly affected by either media exposure condition, advertent (but not inadvertent) media exposure triggered restrained eaters' eating. These results suggest that teaching restrained eaters how to pay less attention to media body ideal images might be an effective strategy in media–literary interventions.     

Stress-induced eating in restrained eaters may not be caused by stress or restraint

Restrained eaters tend to increase and unrestrained eaters to decrease their food intake when stressed. This relationship, though robust, does not appear to be caused by restrained eating or by stress per se. For restraint, evidence indicates that none of the common operationalizations of restraint can account for restraint-related effects that have been examined to date. It is therefore unlikely that restraint is responsible for stress-induced eating in restrained eaters. Rather, behavioral and physiological data suggest that restrained eating may be a proxy risk factor for vulnerability to weight gain. For stress, a variety of minimally stressful perturbations (e.g. non-threatening cognitive loads) have been shown to elicit increased intake in restrained eaters. Thus, the negative affect created by manipulations used to create stress (e.g. scary movies, failure at a task) does not appear to be necessary to provoke overeating. An adequate explanation for stress-induced eating in restrained eaters remains elusive.     

The effects of restraint,gender, and body mass index on the accuracy of self-reported weight

OBJECTIVE: Previous research has shown that women, restrained eaters, and overweight/obese individuals have a tendency to underreport their weight. This study investigated gender, dietary restraint, and BMI to determine which is the best predictor of errors in self-reported weight. METHOD: A total of 241 college students completed questionnaires pertaining to height and weight and then were weighed in the laboratory. RESULTS: Although overall students were fairly accurate in reporting their weight, restraint status was the best predictor of weight underestimation. DISCUSSION: These results suggest that restrained eaters, regardless of gender or BMI, have a tendency to underestimate their weight.     

Behavioral and biological correlates of dietary restraint in normal life

Based on laboratory results, restrained eating has been linked to the development of binge eating and eating disorder syndromes such as bulimia nervosa. This study was designed to extend the scope of investigation of the concept of restrained eating beyond the laboratory. Eating behavior and biochemical indices of nutritional state were investigated in 60 young women, who were divided in restrained and unrestrained eaters by questionnaire. Seven-day records of food intake showed that the high-restraint group ate around 400 kcal a day fewer than the low-restraint group. Group differences in actual macronutrient intake and long-term food preferences pointed to a qualitatively altered eating pattern in restrained eaters. Actual protein portion was higher in restrained eaters. They tried to avoid calorie dense food items of high carbohydrate and fat content. Instead, they preferred food regarded as low-caloric and healthy. Plasma levels of triiodothyronine and glucose, which could be taken as indices of long-term adaptation to starvation, were not decreased in the high-restraint group. However, significantly higher levels of triglycerides in restrained eaters may reflect a biological state due to short-term starvation. The results indicate that the concept of dietary restraint predicts eating behavior not only under experimental conditions, but also in normal life. As a consequence of altered eating patterns, psychological and physiological deprivation can be hypothesized in restrained eaters, making them prone to the occurrence of overeating.     

Psychological measures of eating behavior and the accuracy of 3 common dietary assessment methods in healthy postmenopausal women

BACKGROUND: Factors affecting the accuracy of reported energy intake (rEI) need to be identified. OBJECTIVE: Our objective was to investigate the association of psychological measures of eating behavior with the accuracy of rEI assessed by 7-d weighed intakes, a 24-h recall, and a food-frequency questionnaire. DESIGN: Subjects were 26 restrained eaters aged 60.3 +/- 0.6 y (mean +/- SEM) and weighing 63.8 +/- 1.7 kg and 34 unrestrained eaters aged 59.4 +/- 0.6 y and weighing 64.0 kg. rEI was assessed by using 3 dietary assessment methods and total energy expenditure (TEE) was determined by using doubly labeled water. Calculated EI (cEI) was determined as TEE corrected for the estimated change in body energy. Subjects completed the Eating Inventory. RESULTS: rEI values were significantly lower than TEE values for all 3 dietary assessment methods (P < 0.05); there was no significant relation between rEI and TEE by any method. There was no significant difference in 100 x rEI:TEE between restrained and unrestrained eaters by any of the dietary assessment methods. When combined data from the 3 methods were used, 100 x rEI:cEI was not significantly different from 100% in unrestrained eaters (99 +/- 6.8%) but was lower in restrained eaters (89.1 +/- 5.3%; P < 0.05). There was a positive relation between hunger and 100 x rEI:TEE (P < 0.05). CONCLUSIONS: Low hunger is associated with undereating relative to normal eating during measurement of dietary intake; high dietary restraint may be associated with a reduction in reporting of consumed foods. Dietary hunger and restraint assessed with use of the Eating Inventory may help to identify subjects likely to underreport dietary intake.     

Recorded food intake of obese women with binge eating disorder before and after weight loss

Because binge eating in obese individuals has been postulated to be a reaction to dietary restriction, we examined the recorded food intake of 17 obese women with and 16 obese women without binge eating disorder (BED) during 1-week periods before and 3 months after a very low calorie diet program in order to determine the effects of dietary restriction on binge eating frequency and severity. Before weight loss, rather than reporting severe caloric restriction, women with BED reported greater average energy intake than nonbinge eaters on both a total (2707 vs. 1869 kcal/day, p < .01) and weight-adjusted (25.1 vs. 18.1 kcal/kg, p < .01) basis, with both higher intake on nonbinge days and an increased frequency of binge days. After weight loss, there was no significant difference in energy intake, on either a total or weight-adjusted basis, between subjects with and without BED. Although average daily energy intake fell for both groups after weight loss, only subjects with BED reported significantly decreased energy intake when adjusted for change in body weight. This resulted from decreased intake on nonbinge days and a decreased frequency of binge days. Before weight loss, subjects with BED reported an average energy intake equivalent to 94% of their predicted energy expenditure. Whereas subjects without BED reported intake only 64% of predicted (p = .002). After weight loss, there was no significant difference between subjects with and without BED in the percentage of predicted energy expenditure reported as intake (64% vs. 58%). Restraint was similar in both groups before weight loss, but those with BED reported greater hunger and disinhibition. After weight loss treatment, restraint increased significantly, whereas disinhibition and hunger remained elevated in subjects with BED. Disinhibition, rather than restraint, appears to be a major contributor to the disordered eating of these individuals. Unlike normal-weight women with bulimia nervosa, dietary restriction does not appear to worsen symptoms of bingeeating in obese women with BED. Over the short term, subjects with BED may respond to a standard weight loss treatment program with improvements in binge eating behaviors. © 1994 by John Wiley & Sons, Inc.     

Differences in food-choice frequencies between restrained and unrestrained eaters

Reported frequency of consumption for certain food items was studied in young normal-weight women, classified into 19 unrestrained and 20 restrained eaters by the Three-Factor Eating Questionnaire of Stunkard & Messick (1985). Neither group differed in the consumption of basic foods and snacks but restrained eaters showed a strong tendency to avoid fat. A large percentage of this group was used to consuming artificial sweeteners and other calorie-reduced foodstuffs. These qualitative alterations in the everyday eating behavior of restrained eaters may be one of the links between dietary restraint and binge eating.     

Dietary restraint and weight gain during pregnancy

OBJECTIVES: To explore dietary intake and weight gain during pregnancy in relation to dietary restraint. DESIGN: Longitudinal prospective study. Attitudes to weight gain during pregnancy were assessed using self-administered questionnaires and dietary intake by 7-d weighed diet records in early and late pregnancy. SETTING: South West London 1995-1996. SUBJECTS: 74 Caucasian pregnant women expecting their first or second baby were recruited through a London hospital and data from 62 women were analysed. RESULTS: Restrained eaters were significantly less likely to experience weight gains within the recommended range for their pre-pregnancy body mass index (BMI) (P=0.026). They gained either more or less weight than recommended. CONCLUSIONS: Dietary restraint appears to have undesirable influences on eating and weight gain during pregnancy which require further attention.     

Conformity and dietary disinhibition: a test of the ego-strength model of self-regulation

OBJECTIVE: Ego-strength depletion was examined as an explanation for dietary disinhibition in restrained eaters. We predicted that the depletion of ego strength resulting from having to choose whether to conform would undermine dietary restraint. METHOD: Participants completed an Asch-type conformity task, after which they completed a taste-rating task in which food intake was measured. RESULTS: As predicted, restrained eaters who repeatedly exercised choice ate significantly more than did restrained eaters who did not exercise choice. DISCUSSION: An ego-strength model of dietary restraint is discussed.     

Psychosocial variables associated with binge eating in obese males and females.

OBJECTIVE: This study tested a psychosocial model of binge eating symptoms in obese men and women. Predictor variables included depression, dietary restraint, self-esteem, weight cycling, history of teasing, body dissatisfaction, and neuroticism. METHOD: Participants (N = 808) completed a packet of self-report questionnaires. RESULTS: Weight cycling, teasing about weight and shape, body dissatisfaction, negative affect, and dietary restraint comprised the best fitting models (original and cross-validation) for binge eating in women and men. These variables explained 61-72% of the variance in symptoms of binge eating in the samples of men and 70% of the variance in the samples of women. Although the male and female models were mostly similar, notable differences between them were found. DISCUSSION: The variables that comprise these etiological models should be considered in the development of prevention programs for obese binge eaters. Longitudinal studies, however, are needed to examine these etiological paths and to test for causal relationships.     

Do restrained eaters restrict their caloric intake prior to drinking alcohol?

This research used multilevel modeling to investigate the hypothesis that restrained eaters increase dietary restriction when they expect to drink alcohol. Undergraduate women (39 restrained eaters; 40 unrestrained eaters) monitored their food and alcohol intake for ten days. Restrained eaters, on average, consumed fewer calories per day than unrestrained eaters. Although the intent to drink alcohol did not impact the overall caloric intake of restrained eaters prior to drinking, restrained eaters reported significantly fewer eating episodes than unrestrained eaters on days the participants intended to drink. Given that restrained eaters generally consumed fewer calories per day and had fewer eating episodes prior to drinking, one major implication of higher levels of intoxication would be increased risk of negative alcohol-related consequences. Future research should extend this study and evaluate negative alcohol-related consequences that occur with higher levels of intoxication.     

'The weight of a thought': food-related thought suppression in obese and normal-weight youngsters

OBJECTIVE: The ironic processing theory by Wegner states that suppressing unwanted thoughts can be counterproductive because it leads to a rebound of these thoughts, eventually causing increased preoccupations. In line with this view, the present study examines the effects of suppressing food- and eating- related thoughts in obese and non-obese youngsters. METHOD: Ninety-seven clinically obese and non-obese boys and girls, with different levels of dietary restraint, were asked to monitor their thoughts about food for 5min, during three subsequent trial periods. Participants were instructed to suppress thoughts about food or to merely monitor them. The number of food-related thoughts was recorded across trials. RESULTS: No indication was found for an overall post-suppression rebound effect. However, when examining subgroups of high and low restrained eaters, results showed that the obese high restrained eaters displayed a pattern that was indicative of a rebound effect for food-related thoughts. None of the other groups shared these effects. DISCUSSION: The results corroborate the hypothesis that trying not to think about food and eating may be counterproductive, at least for a subgroup of clinically obese high restrained eaters. Thought suppression may be one of the factors contributing to acceleration and perpetuation of burdensome food-related thinking in clinically obese high restrained eaters.