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Insufficient responses to hypocaloric diets have been attributed to hormonal adaptations that override self-control of food intake. We tested this hypothesis by measuring circulating energy-balance hormones and brain functional magnetic resonance imaging reactivity to food cues in 24 overweight/obese participants before, and 1 and 3 months after starting a calorie restriction diet. Increased activity and functional connectivity in prefrontal regions at month 1 correlated with weight loss at months 1 and 3. Weight loss was also correlated with increased plasma ghrelin and decreased leptin, and these changes were associated with food cue reactivity in reward-related brain regions. However, the reduction in leptin did not counteract weight loss; indeed, it was correlated with further weight loss at month 3. Activation in prefrontal regions associated with self-control could contribute to successful weight loss and maintenance. This work supports the role of higher-level cognitive brain function in body-weight regulation in humans., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This study examined weight control motivation among patients (N=5460 females and 547 males) who sought weight loss treatment with family physicians. An eight-item measure assessed the frequency of thoughts and feelings related to weight control "outcome" (e.g. expected physical and psychological benefits) and "process" (e.g. resentment and doubt). Factor analysis supported the existence of two factors, labeled Positive and Negative motivation. Positive motivation was high (average frequency of thoughts about benefits was 'every day') and stable throughout treatment, while Negative motivation declined rapidly and then stabilized. The determinants of changes in the Positive and Negative dimensions during treatment were examined within 3 time frames: first month, months 2-6, and 6-12. Maintenance of high scores on Positive motivation was associated with higher BMI and more disturbed eating habits. Early reductions in Negative motivation were greater for those starting treatment with higher weight and more disturbed eating habits, but less depression and stress, while later reductions in Negative motivation were predicted by improvements in eating habits, weight, stress and perfectionism. Clinicians treating obesity should be sensitive to fluctuations in both motivational dimensions, as they are likely to play a central role in determining long-term behavior and weight change., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objectives: This study examined early treatment response in obesity treatment, defined as early change in body mass index (BMI) and early change in eating behaviour, as a predictor of ongoing weight loss in obese patients., Methods: We conducted a repeated measures analysis of eating behaviour, emotional factors (depression, stress, perfectionism) and BMI, over a 9 month period. Subjects were 344 females, aged 18-65 (mean = 41.8), with a BMI of at least 25 (mean BMI = 33.7), engaged in very-low calorie (VLCD) or low-calorie (LCD) diets., Results: Multi-level modelling identified four significant predictors of ongoing weight loss (weight loss occurring between 5 weeks and 9 months after the start of treatment). These included: type of diet, early BMI change (start to 5 weeks), number of weigh-ins and the early change in uncontrolled eating (start to 5 weeks). Estimates based on multi-level modelling indicate that patients with strong versus weak early treatment responses would be expected to show large differences in ongoing weight loss., Conclusions: Early improvements in eating behaviour and weight appear to have additive effects in the prediction of ongoing weight change. Future research is required to identify the optimal rate of weight loss, whether there are critical periods for behaviour change, and factors which influence the likelihood of early behaviour change.

A validation study of the Larocque Obesity Questionnaire designed for use in obesity treatment was performed. Unlike other measures of obesity, this questionnaire includes scales measuring general emotional state as well as eating behavior. Subscales measured uncontrolled eating, physical stress responses, depression, and perfectionism. Subjects were 458 women and 79 men in treatment for obesity by general practitioners. The subscales showed acceptable internal consistency and related in predictable ways to measures of eating behavior, depression, self-criticism, stress, physical complaints and weight-control motivation. Subjects in the heaviest weight category (Body Mass Index > or = 40) showed higher scores on Stress Response and Depression subscales. There were no significant sex differences, after controlling for weight. All four subscales showed significant improvement after 5 wk., which indicates their sensitivity to changes during treatment.