Effects of models on food intake of obese and non-obese female college students.

Compared the effects of a model on the food intake of obese and nonobese females. 20 obese and 20 nonobese female Ss were paired with an experimental confederate who was either obese or nonobese. Analysis of the amount of food eaten revealed an interaction between weight status and type of confederate: obese Ss ate significantly more in the presence of an obese confederate. By contrast, nonobese Ss ate a similar amount in both conditions. There was a significant difference between the amount Ss ate and the amount they reported they had eaten, due largely to the fact that obese Ss underestimated the amount of food they had eaten. (French summary) (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of parent weight on weight loss in obese children.

Assessed the effect of parent weight (obese/nonobese parent) and parent control vs child self-control on the weight loss of 41 obese 8–12 yr olds over a 3-yr period. Children of nonobese parents had significantly greater decrease in relative weight after 1 yr, but not after 3 yrs, than children of obese parents. Locus of control was not related to treatment outcome over the 3 yrs. Results suggest that parent weight was related to weight loss, but not weight maintenance, in obese children. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anxiety and eating behavior in obese and nonobese American Indians and White Americans.

Compared 80 lower-SES obese and nonobese American Indians and 80 lower-SES obese and nonobese White Americans from multinational backgrounds on a test of emotional arousal theory (EAT), which proposes that obese people overeat when emotionally aroused while nonobese people do not. Ss were administered the trait anxiety form of the State-Trait Anxiety Inventory (STAI) and then assigned to a high-anxiety (HA) or low-anxiety condition. They were then administered the state form of the STAI and given a taste task to determine whether EAT is predictive of eating behaviors for both ethnic groups. Results indicate that women were more trait and state anxious than were men; HA women, all HA Ss, HA American Indians, and nonobese American Indians were more state anxious than were corresponding groups. Behavioral indicator results generally supported EAT: All obese and high-anxiety-condition obese Ss consumed more food than did nonobese and low-anxiety-condition obese Ss, respectively. The overall consumption of food was greater with American Indians than with White Americans, indicating that EAT does not fully explain American Indian eating behavior. An alternative stress-reaction theory is proposed to more fully account for American Indian eating behavior. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Revising and validating the random search model for competitive search

The aim of the present study is a comparison of family relations in families with an obese adolescent and families with a normal-weight adolescent. Particularly, we studied the parents' and children's perceptions of some crucial areas of their relationship, e.g., communication, support, and some factors of "psychosocial risk" for the adolescents. We compared 30 family triads each with an obese child and 30 family triads each with a normal-weight child. We used a questionnaire aimed to evaluate some crucial variables of family functioning such as communication, family climate, support and satisfaction. A multivariate analysis of variance yielded no difference between obese and nonobese adolescents concerning communication with their mothers and fathers and concerning support given and received from them. In particular, analysis indicated no difference between parents of obese adolescents and parents of normal-weight adolescents regarding openness and problems in communication. As a protective factor against psychosocial risk, in both the samples the relationship with the mother arises as relevant, but, for the nonobese adolescents, both support and communication with this parent were important, whereas for the obese adolescents only support seemed to be really important. The results are discussed with respect to this approach which considered the family as the unit of analysis both from a theoretical and a methodological point of view.     

Effect of depressed mood on eating among obese and nonobese dieting and nondieting persons.

Induced a depressed or nondepressed mood in obese and nonobese dieters and nondieters (18 male and 38 female undergraduates). Ss were administered a battery of measures, including the Beck Depression Inventory and Depression Adjective Check List. As predicted, dieters ate more when depressed than when nondepressed, and nondieters ate less when depressed than when nondepressed. That is, both groups reversed their typical eating patterns when depressed. Also as predicted, among depressed Ss, dieters ate more than nondieters; among nondepressed Ss dieters ate less that nondieters. This pattern of results was found for both obese and nonobese Ss. Dieting habits were highlighted as a more salient variable than obesity in predicting eating responses to depressed mood. Findings are discussed with respect to the psychosomatic theory of obesity, the stimulus-binding theory of obesity, previous investigations of clinical depression, and the theory of restrained eating. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of obesity on the response to insulin therapy in noninsulin-dependent diabetes mellitus

An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol.     

Lipoprotein(a) in android obesity and NIDDM

OBJECTIVE: To assess the level of serum lipoprotein(a) [Lp(a)] in nonobese and obese NIDDM subjects with android body distribution. RESEARCH DESIGN AND METHODS: Serum Lp(a) levels were measured in 30 long-standing NIDDM patients (duration of diabetes 12.5 +/- 3 years, mean +/- SD), with 15 of the patients being obese of android distribution (BMI > 30 kg/m2 and waist-to-hip ratio > 0.8). In addition, there were 15 android obese nondiabetic subjects and 10 healthy subjects serving as the control group. RESULTS: All groups of patients in this study (diabetic, obese, and obese diabetic) showed significantly higher levels of Lp(a) than the healthy control group. Lp(a) concentrations were significantly higher in NIDDM patients with android type of obesity than in nondiabetic androids (24.1 +/- 5.6 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Significantly greater levels of Lp(a) were found in nonobese subjects with diabetes when compared with obese subjects without diabetes (22.3 +/- 4.1 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Furthermore, Lp(a) serum concentrations were not dependent on the degree of glycemic control (controlled NIDDM 23.6 +/- 5.0 vs. uncontrolled NIDDM 21.4 +/- 2.7 mg/dl, NS), but were much greater in subjects with diabetes complicated by vascular disease (complicated 26.3 +/- 5.0 vs. uncomplicated 20.5 +/- 2.7 mg/dl, P < 0.001). No correlation was found between Lp(a) and other lipid parameters in this study. CONCLUSIONS: Lp(a) levels are significantly elevated in both android-obese and nonobese NIDDM patients regardless of the degree of glycemic control. Lp(a) is an independent risk factor showing greater elevations in those subjects complicated with diabetic vascular diseases.     

Pain sensitivity in dietary-induced obese rats

Previous literature indicates possible interrelationships between the endogenous opioids or endorphins, pain response, and obesity or eating behaviour. The pain response was, therefore, examined in a rat model of obesity induced by palatable food high in unsaturated fats. Pellet-fed control and energy-dense obese and nonobese rats were tested for latency of response to a thermal stimulus using the tail flick test. Obese rats exhibited a statistically significant increase in tail flick latency compared to controls. In addition, the observed latencies were significantly correlated to the body weight of the rats (r = 0.52, p < 0.01). These data suggest that dietary-induced obese rats are similar to obese humans in being less sensitive to painful stimuli, consistent with an increase in endogenous opioids in obesity.     

Ventromedial syndrome: The rat's "finickiness" results from the obesity, not from the lesions.

6 obese, finicky female hooded rats with lesions of the hypothalamic ventromedial nucleus (VMH) and 7 sham-lesioned controls progressively lost weight on an unpalatable diet until at a critical basal level they increased their intake to prevent further loss of weight. The critical basal body weight was similar in both groups and showed no change in the controls when they were subsequently lesioned and retested. At weight levels below the critical basal level the feeding behavior of lesioned and unlesioned Ss was similar, and finickiness could be demonstrated only when body weight exceeded it. The basal level bore no relation to the plateau level of body weight reached by Ss on a free diet. Suggestions that the VMH excites as well as inhibits feeding seem untenable in view of the failure of VMH lesions to impair defense of body weight in the nonobese rat. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conditioned taste aversion in lean and obese rats with ventromedial hypothalamic knife cuts.

Assessed the development of a conditioned taste aversion (CTA) in 60 female Sprague-Dawley rats made hyperphagic with parasagittal knife cuts in the ventromedial hypothalamus (VMH). Ss were water deprived and presented with a .1% saccharin solution paired with injections of either LiCl or NaCl. In Exp I, VMH Ss tested at a nonobese weight level did not differ from sham-operated controls in acquisition and extinction of the CTA. In Exp II, moderately obese VMH Ss displayed a stronger CTA than did sham-operated controls as evidenced by slower extinction. A 2nd group of obese VMH Ss given an amount of LiCl equivalent to that given to the controls also displayed retarded extinction of the CTA. Results reflect an obesity-induced suppression in appetitive motivation. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of oral glucose administration on plasma growth hormone levels in women with polycystic ovary syndrome

OBJECTIVE: To evaluate the sensitivity of GH secretion to the suppressive effect of oral glucose administration in women with polycystic ovary syndrome (PCOS). DESIGN: Comparison of the GH response to an oral glucose load in women with PCOS and in weight-matched normally menstruating women (controls). SETTING: Reproductive endocrinology unit. PATIENT(S): Eighteen obese and 11 nonobese patients and 10 obese and 10 nonobese controls. INTERVENTION(S): After an overnight fast, each woman underwent a 75-g, 3-hour oral glucose tolerance test (OGTT). MEAN OUTCOME MEASURE(S): Growth hormone, glucose, and insulin responses to OGTT. RESULT(S): No significant differences in the glycemic and insulinemic responses were found between the patients and the weight-matched controls. No decrease in plasma GH was observed in both obese and nonobese patients and in obese controls during the OGTT, whereas a significant GH decrease occurred in nonobese controls 60 and 120 minutes after glucose intake. CONCLUSION(S): Oral glucose administration was unable to suppress GH levels in nonobese as well as in obese women with PCOS and in obese control women. These data suggest that both PCOS and obesity are associated with a reduced sensitivity of GH secretion to glucose suppression.     

Impaired endothelium-dependent vasodilatation in women with previous gestational diabetes

OBJECTIVE: To assess whether otherwise healthy women with a history of gestational diabetes mellitus (GDM) may have abnormalities in endothelial function at a very early stage, before glucose intolerance occurs. RESEARCH DESIGN AND METHODS: A total of 33 women with previous GDM (17 nonobese [BMI < 27] and 16 obese [BMI > or = 27]) and 19 healthy nonobese women were examined. A 75-g oral glucose tolerance test was performed, and insulin levels and biochemical parameters were also measured. Using high-resolution ultrasound, we measured vasodilatory responses of the brachial artery during reactive hyperemia (endothelium-dependent vasodilatation), and after nitroglycerin administration, an endothelium-independent vasodilator. RESULTS: Flow-mediated dilatation (FMD) was significantly and equally decreased in both groups of women with previous GDM, compared with control subjects (1.6 +/- 3.7% in the nonobese GDM group and 1.6 +/- 2.5% in the obese GDM group vs. 10.3 +/- 4.4% in control subjects, P < 0.001). FMD correlated inversely with serum uric acid levels, BMI, serum total cholesterol, and basal insulin resistance (homeostasis model assessment). Nitrate-induced dilatation was significantly decreased only in the obese GDM group compared with control subjects, (21.4 +/- 5.1 vs. 27.9 +/- 9.5, P < 0.05). CONCLUSIONS: Endothelial dysfunction, which is considered as a very early index of atherogenesis, is already present in both obese and nonobese women with a history of GDM, even when they have normal glucose tolerance.     

The motor organization of the sense of rhythm

Serum inorganic fluoride levels in obese versus control patients were compared during and after sevoflurane anesthesia. Mean serum inorganic fluoride levels in the obese group increased more rapidly and were significantly higher than in the control group at each sampling time (P < 0.01). The area under the curve of fluoride concentration, versus time up to 24 h and 48 h in the obese patients, was significantly greater than that in the nonobese patients (P < 0.001). Peak serum fluoride level in the obese patients was 51.7 +/- 2.5 mumol/L and exceeded 50 mumol/L for nearly 2 h. Our study showed that serum fluoride concentrations between mildly obese and nonobese patients differed during and after sevoflurane anesthesia.     

Circulating fatty acids are essential for efficient glucose-stimulated insulin secretion after prolonged fasting in humans

In the fasted rat, efficient glucose-stimulated insulin secretion (GSIS) is absolutely dependent on an elevated level of circulating free fatty acids (FFAs). To determine if this is also true in humans, nonobese volunteers were fasted for 24 h (n = 5) or 48 h (n = 5), after which they received an infusion of either saline or nicotinic acid (NA) to deplete their plasma FFA pool, followed by an intravenous bolus of glucose. NA treatment resulted in a fall in basal insulin concentrations of 35 and 45% and in the area under the insulin response curve (area under the curve [AUC]) to glucose of 47 and 42% in the 24- and 48-h fasted individuals, respectively. The 48-h fasted subjects underwent the same procedure with the addition of a coinfusion of Intralipid plus heparin (together with NA) to maintain a high concentration of plasma FFAs throughout the study. The basal level and AUC for insulin were now completely normalized (C-peptide profiles paralleled those for insulin). To assess the effect of an overnight fast, nonobese (n = 6) and obese (n = 6) subjects received an infusion of either saline or NA, followed by a hyperglycemic clamp (200 mg/dl). The insulin AUC in response to glucose was unaffected by lowering of the FFA level in nonobese subjects, but fell by 29% in the obese group. The data clearly demonstrate that in humans, the rise in circulating FFA levels after 24 and 48 h of food deprivation is critically important for pancreatic beta-cell function both basally and during subsequent glucose loading. They also suggest that the enhancement of GSIS by FFAs in obese individuals is more prominent than that seen in their nonobese counterparts.     

Olfactory mucosa of the South American armadillo Chaetophractus villosus: an ultrastructural study

OBJECTIVE: Morbidly obese individuals are unlikely to reach and maintain normative weights. Thus, interventions aimed at alleviating corollary problems, independent of attempts at weight loss, are appropriate. A cognitive group treatment program (CT) was developed which incorporated a nondieting approach, regular exercise, and use of alternative coping skills. Weight loss per se was not a focus of the intervention. The purpose of the current work was to evaluate this program in a controlled, comparative treatment outcome study. METHOD: Sixty-two obese women with a history of treatment failures were randomly assigned to the CT program, a behavior therapy weight loss program (BT), or a wait-list control group. RESULTS: For CT participants, depression, anxiety, and eating-related psychopathology decreased significantly over the course of treatment while perceptions of self-control increased; BT and control subjects showed no significant changes in these variables. Women in both active treatment groups lost significant amounts of weight, while members of the control group showed a nonsignificant increase in weight. At 6-month follow-up, treatment benefits were maintained. DISCUSSION: Findings suggest that interventions not directly aimed at weight loss can enhance psychological well-being and thus may be appropriate for some obese women.     

A comparison of weight control and weight control plus body image therapy for obese men and women.

Participants were 65 obese men and women who were randomly assigned to either weight control or weight control plus cognitive–behavioral body image therapy. Both conditions showed clinically significant improvements in body image at posttreatment and 1-year follow-up. Adding body image therapy to weight control did not result in greater psychological improvements and did not result in better maintenance of body image change when participants regained weight after treatment. Weight loss and maintenance were equivalent between groups. Adding body image therapy did not improve or detract from weight loss. Although body image therapy has been shown to be effective in obese persons, it appears that a well-rounded cognitive–behavioral weight control program is effective as well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serotonin transporter gene-linked polymorphic region: allele distributions in relationship to body weight and in anorexia nervosa

Several lines of evidence implicate a role for the serotonergic system in body weight regulation and eating disorders. The magnitude and duration of postsynaptic responses to serotonin (5-HT) is directed by the transport into and release from the presynaptic neuron. Recently, a common polymorphism of a repetitive element in the region of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) was identified that results in a system of two common alleles. The activity of the 5-HTT, as measured in in vitro assays and in human lymphoblastoid cell lines, is dependent on the respective genotype. We thus hypothesized that this polymorphism is relevant for weight regulation in general and is possibly involved in the etiology of anorexia nervosa (AN). Allele frequencies and genotypes were determined in a total of 385 unrelated obese children, adolescents and adults, 112 underweight subjects and 96 patients with AN. Furthermore, both parents of 98 obese children and adolescents and of 55 patients with AN, respectively, were genotyped, thus allowing to test for both association and linkage. The comparison of allele frequencies between obese and underweight probands provided no evidence for a major role of the 5-HTTLPR in weight regulation. Patients with AN had allele frequencies not significantly different to those observed for obese and underweight individuals.     

Exercise testing of the child with obesity

As the prevalence of childhood obesity increases, exercise testing of obese children is likely to increase as well. This article discusses the implications of pediatric obesity for exercise testing and provides some recommendations for conducting tests and evaluating results. Studies comparing obese and nonobese children during exercise testing indicate that obese children are capable of meeting the challenges of exercise testing to nearly the same extent as their nonobese peers. Their physiologic responses, at least for the levels of obesity reported in the literature, are not sufficiently different from their nonobese counterparts to necessitate major changes in test protocols. Laboratory staff should pay special attention to fostering confidence in the obese child during the pretest routine.     

Do obese women have poorer social relationships than nonobese women? Reports by self, friends, and coworkers

Both theory and research suggest that obese women may have relatively poor social relationships even if their self-reports about their relationships do not differ from the reports of nonobese women. Seventy-seven obese and 78 nonobese women completed self-report measures of social anxiety, social self-esteem, social competence, social network size, and perceived social support from friends and family. Friends and coworkers also rated these women on the same measures. The self-reports of obese and nonobese women did not differ significantly on any of these social measures, and ratings from friends and coworkers of obese women were not different from ratings of nonobese women by friends and coworkers. These results suggest that obese women may be able to overcome prejudice against obese people in their relationships with others.