Total energy expenditure as measured by doubly-labeled water in outpatients with bulimia nervosa

The Role of Exercise Dependence for the Relationship between Exercise Behavior and Eating Pathology

Our study examined the potential mediating or moderating effect of exercise dependence on the exercise—eating pathology relationship. Female university students ( N = 330) completed Internet-based self-report measures of exercise behavior, exercise dependence, and eating pathology. Exercise dependence served as a mediator for the relationship between exercise and eating pathology. This unidirectional causal model suggests that an individual's pathological motivation or compulsion to exercise is the critical mediating component in the exercise—eating pathology relationship. The best target for removing the link between exercise behavior and eating pathology may be reformulating exercise dependence symptoms.

Effects of binge eating behavior on fuel oxidation and body composition

OBJECTIVE

To investigate energy expenditure and glucose metabolism after a standard oral glucose load (75 g) in 8 normal weight bulimic women and 8 normal weight control women and to evaluate the relative endocrine implication.

DESIGN

Serum glucose and insulin were measured both in basal conditions and after the glucose load; a basal endocrine assessment and body composition was evaluated and glucose induced thermogenesis (GIT) was calculated during 300 min following the glucose load.

RESULTS

Serum glucose levels were significantly lower in bulimics both in fasting and in post-prandial state. Insulin levels were similar in bulimic and control women before and after the glucose load. FSH, leptin and free urinary cortisol (FUC) were all within the normal ranges, but significantly lower in bulimic patients compared with controls (p < 0.001). Fat mass (FM) and Fat-free mass (FFM) were reduced in bulimic patients, even if they normalized after correction per body weight. Resting energy expenditure (REE) was similar in the two groups even after FFM normalization, while GIT was lower in bulimic patients and it was strongly related to free urinary chortisol. Glucose oxidation was higher in fasting state and post glucose load, while lipid oxidation was strongly reduced.

CONCLUSION

An energy preservation mechanism seems to be the key element for normal-weight bulimic patients' metabolism, consisting in leptin levels and GIT reduction, and lipid oxidation inhibition.

Research on energy expenditure in individuals with eating disorders: a review

OBJECTIVE

This study reviews the published research on energy expenditure in individuals with anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED).

METHOD

Individual studies are reviewed and their results summarized.

RESULTS

The most consistent finding is a reduction in resting energy expenditure (REE) in patients with AN, which increases with increased energy intake and body weight. Data regarding BN are inconsistent. Three available studies in subjects with BED have not found evidence of changes in energy expenditure corrected for lean body mass compared with obese non-binge eaters.

DISCUSSION

The ability to measure REE reliably and cost-effectively may aid in the refeeding of patients with AN in whom REE is reduced. Changes in individuals with BN and BED have yet to be consistently identified.

Research on energy expenditure in individuals with eating disorders: a review

OBJECTIVE

This study reviews the published research on energy expenditure in individuals with anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED).

METHOD

Individual studies are reviewed and their results summarized.

RESULTS

The most consistent finding is evidence of reduction in resting energy expenditure (REE) in patients with AN, which increases with increased energy intake and body weight. Data regarding BN are inconsistent. Three available studies in subjects with BED have not found evidence of changes in energy expenditure corrected for lean body mass compared with obese non-binge eaters.

DISCUSSION

The ability to reliably and cost-effectively measure REE may aid in the refeeding of patients with AN where REE is reduced. Changes in BN and BED subjects have yet to be identified consistently.

Serum cholesterol in bulimia nervosa

OBJECTIVE

The purpose of this retrospective study was to replicate and to extend previous work indicating that bulimia nervosa is associated with elevated serum levels of cholesterol and to examine the association between cholesterol and other clinical and serum measures.

METHODS

Clinical characteristics and laboratory data including nonfasting cholesterol and thyroid indices were collected from charts of 119 women with bulimia nervosa and 42 female controls.

RESULTS

There was no significant difference between the two groups in mean age or body mass index. The mean serum cholesterol level of the patient group was statistically significantly greater than that of the control group (patients: 194 +/- 36 mg/dl; controls: 176 +/- 34 mg/dl; t = 2.77; df = 159; p =.006). The mean calculated free T4 of the bulimia nervosa patient group was statistically lower than that of the control group (patients: 1.89 +/- 0.32; controls: 2.09 +/- 0.26; t = 2.86; df = 141; p =.005). There was no correlation between calculated free T4 and serum cholesterol within the combined group (r =.04, p >.5, N = 143) or within the patient group (r =.08, p >.3, N = 118).

CONCLUSIONS

The average serum level of cholesterol is elevated in the patients with bulimia nervosa. The mechanism for and the consequences of this abnormality are uncertain.