Cognitive dietary restraint: Impact on bone, menstrual and metabolic status in young women

We compared bone mineral density (BMD) and content (BMC), menstrual and metabolic status between physically active women with 1) high cognitive dietary restraint (High-CDR) (score >= 9, n=38) and Normal-CDR (score<9, n=46) and 2) across quartiles of CDR scores. Eighty-four physically active (500 +/- 35 min wk(-1)) premenopausal women participated and were categorized according to their CDR score. Primary outcomes included, BMD, BMC, menstrual status, estrone-3-glucuronide (E1G) and pregnanediol-3-glucuronide (PdG) area under the curve (AUC). Secondary outcomes included resting energy expenditure (REE), total triiodothyronine, and ghrelin. Measures of body mass (59.2 +/- 1.1 vs. 58.5 +/- 1.0 kg) and percent body fat (24.7 +/- 1.2 vs. 23.7 +/- 0.7%) were similar between women with Normal-CDR and High-CDR, however the High-CDR group had lower total body (1.140 +/- 0.011 vs. 1.179 +/- 0.010 g cm(-2); p=0.015) and lumbar spine (1.114 +/- 0.019 vs. 1.223 +/- 0.022 g cm(-2); p=0.001) BMD. The prevalence of oligo-amenorrhea was higher in the High-CDR group and became increasingly greater across the CDR quartiles. There were no differences in metabolic characteristics between the High-CDR and Normal-CDR groups, however REE and the ratio of measured to predicted REE were lower in the fourth quartile (CDR scores >= 13) compared to the second and third quartiles. Our results provide evidence that high CDR scores are associated with reduced lumbar spine and total body BMD in physically active premenopausal women. A greater frequency of menstrual disturbances in women with higher CDR scores likely played a role in the reduced total body and lumbar spine BMD. (C) 2008 Elsevier Inc. All rights reserved.