title: Bone turnover and density in obese premenopausal women during moderate weight loss and calcium supplementation.
abstract: Bone turnover is increased during weight loss in postmenopausal women and can be suppressed with calcium supplementation. In this study, we assessed the influence of energy restriction with and without calcium supplementation (1 g/day) in premenopausal women. Thirty-eight obese premenopausal women (body mass index [BMI] of 35.0 +/- 3.9 kg/m2) completed a 6-month study of either moderate weight loss or weight maintenance. During weight loss, women were randomly assigned to either a calcium supplementation (n = 14) or placebo group (n = 14) and lost 7.5 +/- 2.5% of their body weight. The control group of women (n = 10) maintained their body weight. Total body and lumbar bone mineral density (LBMD) and content were measured by dual-energy X-ray absorptiometry (DXA) at baseline and after weight loss. Throughout the study, blood and urine samples were collected to measure bone turnover markers and hormones. During moderate energy restriction, dietary calcium intake decreased (p < 0.05) and the bone resorption marker deoxypyridinoline (DPD) increased slightly (p < or = 0.05) without evidence of bone loss. Calcium supplementation during weight loss tended to increase lumbar BMD by 1.7% (p = 0.05) compared with the placebo or weight maintenance groups. In contrast to our previous findings in postmenopausal women, premenopausal obese women who consume a low calcium diet do not lose bone over a 6-month period, whether their weight is stable or decreasing moderately.
authors.affiliation: Department of Nutritional Sciences, Rutgers University, New Brunswick, New Jersey 08901-8525, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Shapses
authors.forename: N L
authors.initials: NL
authors.lastname: Von Thun
authors.forename: S B
authors.initials: SB
authors.lastname: Heymsfield
authors.forename: T A
authors.initials: TA
authors.lastname: Ricci
authors.forename: M
authors.initials: M
authors.lastname: Ospina
authors.forename: R N
authors.initials: RN
authors.lastname: Pierson
authors.forename: T
authors.initials: T
authors.lastname: Stahl
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000596:Amino Acids / Q000032:analysis / Q000652:urine; D015992:Body Mass Index; D015519:Bone Density / Q000187:drug effects* / Q000502:physiology*; D001862:Bone Resorption / Q000188:drug therapy / Q000503:physiopathology*; D002136:Calcium, Dietary / Q000494:pharmacology* / Q000627:therapeutic use; D003094:Collagen / Q000378:metabolism; D024042:Collagen Type I; D019587:Dietary Supplements; D004311:Double-Blind Method; D002149:Energy Intake; D004970:Estrone / Q000378:metabolism; D005260:Female; D005508:Food Deprivation; D006801:Humans; D008159:Lumbar Vertebrae / Q000187:drug effects / Q000502:physiology; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*; D015675:Osteocalcin / Q000097:blood / Q000378:metabolism; D010281:Parathyroid Hormone / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D017697:Premenopause / Q000502:physiology*; D011726:Pyridinium Compounds / Q000378:metabolism / Q000652:urine; D014807:Vitamin D / Q000378:metabolism; D015431:Weight Loss / Q000502:physiology*
chemical_list: D000596:Amino Acids; D002136:Calcium, Dietary; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; D011726:Pyridinium Compounds; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D014807:Vitamin D; D004970:Estrone; C036020:deoxypyridinoline; D003094:Collagen