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Psychobiological effects associated with a progressive body weight loss may help to improve the understanding of psychological barriers to weight loss. We hypothesized that a moderate body weight loss (about 10% of initial body weight) is accompanied with some negative psychological impact. Four questionnaires [SF-36 Health Survey, Three-Factor Eating Questionnaire (TFEQ), Beck Depression Inventory (BDI) and Pittsburgh Sleep Quality Index (PSQI)] were administered at each phase of a body weight loss program that consisted of a supervised diet and exercise clinical intervention to 11 obese men (mean BMI = 33.4 kg/m(2), mean age = 38 yr). The three phases investigated were: 1) at the beginning of the intervention (baseline); 2) after 5 +/- 1 kg body weight loss (Phase 1); and 3) after 10 +/- 1 kg body weight loss (Phase 2). Using the SF-36 Health Survey, physical and mental health were shown to be significantly improved at Phase 1 (p < 0.05). The TFEQ showed that cognitive dietary restraint increased (p < 0.001), and both disinhibition (p < 0.05) and susceptibility to hunger (p < 0.05) were significantly reduced at both Phase 1 and 2 compared to baseline. Depression as measured by the BDI significantly increased at Phase 2 (p < 0.05) compared to baseline and Phase 1. However, the mean BDI scores observed remained below the cut-off point for likely clinical significance. Finally, the PSQI showed that sleep quality was significantly improved at Phase 1 compared to baseline (p < 0.01). Altogether, these results suggest that a substantial improvement in the psychobiological profile occurs with a 5-kg weight loss (Phase 1) but that with additional weight loss (Phase 2) a small, but significant increase in depression occurred and seems to be associated with the increase in rigid restraint of eating. However, prospective studies with a larger sample are needed to confirm and deepen these results.

Objective: It is commonly recognized that genetic, environmental, behavioral, and social factors are involved in the development of obesity. The family environment may play a key role in shaping children's eating behaviors. The purpose of this study was to estimate the degree of familial resemblance in eating behavioral traits (cognitive dietary restraint, disinhibition, and susceptibility to hunger)., Research Methods and Procedures: Eating behavioral traits were assessed with the Three-Factor Eating Questionnaire in 282 men and 402 women (202 families) from the Quebec Family Study. Familial resemblance for each trait (adjusted for age, sex, and BMI) was investigated using a familial correlation model., Results: The pattern of familial correlation showed significant spouse correlation for the three eating behavior phenotypes, as well as significant parent-offspring and sibling correlations for disinhibition and susceptibility to hunger. According to the most parsimonious model, generalized heritability estimates (including genetic and shared familial environmental effects) reached 6%, 18%, and 28% for cognitive dietary restraint, disinhibition, and susceptibility to hunger, respectively., Discussion: These results suggest that there is a significant familial component to eating behavioral traits but that the additive genetic component appears to be small, with generalized heritability estimates ranging from 6% to 28%. Thus, non-familial environmental factors and gene-gene and gene-environmental interactions seem to be the major determinants of the eating/behavioral traits.

Background: Obesity is frequently associated with eating disorders, and evidence indicates that both conditions are influenced by genetic factors. However, little is known about the genes influencing eating behaviors., Objective: The objective was to identify genes associated with eating behaviors., Design: Three eating behaviors were assessed in 660 adults from the Quebec Family Study with the use of the Three-Factor Eating Questionnaire. A genome-wide scan was conducted with a total of 471 genetic markers spanning the 22 autosomes to identify quantitative trait loci for eating behaviors. Body composition and macronutrient and energy intakes were also measured., Results: Four quantitative trait loci were identified for disinhibition and susceptibility to hunger. Of these, the best evidence of linkage was found between a locus on chromosome 15q24-q25 and disinhibition (P <0.0058) and susceptibility to hunger (P <0.0001). After fine-mapping, the peak linkage was found between markers D15S206 and D15S201 surrounding the neuromedin beta (NMB) gene. A missense mutation (p.P73T) located within the NMB gene showed significant associations with eating behaviors and obesity phenotypes. The T73T homozygotes were 2 times as likely to exhibit high levels of disinhibition (odds ratio: 1.8; 95% CI: 1.07, 2.89; P=0.03) and susceptibility to hunger (odds ratio: 1.9; 95% CI: 1.15, 3.06; P=0.01) as were the P73 allele carriers. Six-year follow-up data showed that the amount of body fat gain over time in T73T subjects was >2 times that than in P73P homozygotes (3.6 compared with 1.5 kg; P <0.05)., Conclusion: The results suggest that NMB is a very strong candidate gene of eating behaviors and predisposition to obesity.

The purpose of the present cross-sectional study was to compare eating behaviours (cognitive dietary restraint, disinhibition and susceptibility to hunger), dietary profile and physiological variables according to the practice of dieting: current dieting; history of dieting in the 10-year period that preceded the study; no dieting during the same period. Dieting history, anthropometric markers of adiposity, RMR, dietary profile (3 d food record) and eating behaviours (three-factor eating questionnaire) were determined in a sample of 244 men and 352 women. A greater proportion of women (31.8 %) than men (16.8 %) reported that they had been on a diet over the past 10 years (P=0.0001). In both genders, current and past dieters had a higher BMI (P<0.05) than non-dieters and current dieters had lower reported energy intakes than past dieters and non-dieters (only in women) (P<0.05). Current and past dieters also had higher scores for all eating behaviours and their subscales (P<0.05; except for susceptibility to hunger in men) compared with non-dieters (adjusted for age, reported energy intake, percentage of dietary fat, BMI and RMR). Moreover, for each dieting-history category, women had significantly higher scores for cognitive dietary restraint than men (P<0.05). In conclusion, the present study showed that current and past dieters had higher scores for cognitive dietary restraint and disinhibition compared with non-dieters. As disinhibition has previously been associated with a greater risk of subsequent weight gain, interventions aimed at preventing an increase in disinhibition may be promising for long-term weight maintenance.

Objective: To put into relationship the dietary and anthropometric profile of men and women with their eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) and to assess whether gender and obesity status influence these associations., Research Methods and Procedures: Anthropometric measurements (including visceral adipose tissue accumulation), dietary profile (3-day food record), and eating behaviors (Three-Factor Eating Questionnaire) were determined in a sample of 244 men and 352 women., Results: Women had significantly higher cognitive dietary restraint and disinhibition scores than men (p < 0.0001). In both genders, scores for disinhibition and susceptibility to hunger, but not for cognitive dietary restraint, were higher in obese subjects than in overweight and nonobese subjects (p < 0.05). Positive correlations were observed between rigid restraint and most of the anthropometric variables studied (0.12