Sex differences in the association between dietary restraint, insulin resistance and obesity.
OBJECTIVE
Restrained food consumption may alter metabolic function and contribute to eventual weight gain; however, sex differences in these relationships have not been assessed. The objective of this study was to examine the relationship between restrained eating and insulin resistance and the influence of body mass index and sex on this relationship in a large community sample of both men and women. We hypothesized that restrained eating would be related to insulin resistance and this relationship would be influenced by sex and body mass index.


METHODS
In this cross-sectional, observational study, we studied 487 individuals from the community (men N = 222, women N = 265), who ranged from lean (body mass index 18.5-24.9 kg/m(2), N = 173), overweight (body mass index 25-29.9 kg/m(2), N = 159) to obese (body mass index >30 kg/m(2), N = 155) weight categories. We assessed restrained eating using the Dutch Eating Behavior Questionnaire and obtained fasting morning plasma insulin and glucose on all subjects.


RESULTS
In men, but not in women, restrained eating was related to homeostatic model assessment of insulin resistance (HOMA-IR) (p < 0.0001). Furthermore, HOMA-IR was significantly higher in men who were high- versus low-restrained eaters (p = 0.0006).


CONCLUSIONS
This study is the first to report sex differences with regard to the relationship between restrained eating and insulin resistance. Our results suggest that high restrained eating is associated with insulin resistance in men but not in women.
Department of Internal Medicine, Division of Endocrinology, 333 Cedar Street, Yale University School of Medicine, New Haven, CT 06520, United States; Department of Pediatrics, Division of Pediatric Endocrinology, 333 Cedar Street, Yale University School of Medicine, New Haven, CT 06520, United States. Electronic address: Ania.Jastreboff@yale.edu.
Ania M
AM
Jastreboff
Department of Psychiatry, Yale University School of Medicine, Yale Stress Center, 2 Church Street South, Suite 209, New Haven, CT 06520, United States. Electronic address: Edward.Gaiser@yale.edu.
Edward C
EC
Gaiser
Department of Psychiatry, Yale University School of Medicine, Yale Stress Center, 2 Church Street South, Suite 209, New Haven, CT 06520, United States. Electronic address: Peihua.Gu@yale.edu.
Peihua
P
Gu
Department of Psychiatry, Yale University School of Medicine, Yale Stress Center, 2 Church Street South, Suite 209, New Haven, CT 06520, United States; Child Study Center, Yale University School of Medicine, New Haven, CT 06520, United States. Electronic address: Rajita.Sinha@yale.edu.
Rajita
R
Sinha
D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004038:Diet, Reducing / Q000523:psychology*; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology*; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D055815:Young Adult
Dietary restraint; Insulin resistance; Obesity; Restrained eating; Sex differences