title: Effect of weight loss and exercise therapy on bone metabolism and mass in obese older adults: a one-year randomized controlled trial.
abstract: BACKGROUND
  Although weight loss and exercise ameliorates frailty and improves cardiac risk factors in obese older adults, the long-term effect of lifestyle intervention on bone metabolism and mass is unknown.
  
  
  OBJECTIVE
  The objective was to evaluate the effects of diet-induced weight loss in conjunction with exercise on bone metabolism and mass in obese older adults.
  
  
  METHODS
  We conducted a one-year randomized, controlled clinical trial in a university-based research center.
  
  
  METHODS
  Twenty-seven frail, obese (body mass index = 39 +/- 5 kg/m(2)), older (age 70 +/- 5 yr) adults participated in the study.
  
  
  METHODS
  Participants were randomly assigned to diet and exercise (treatment group; n = 17) or no therapy (control group; n = 10).
  
  
  METHODS
  Body weight decreased in the treatment group but not in the control group (-10 +/- 2 vs. +1 +/- 1%, P < 0.001). Compared with the control group, the treatment group had greater changes in bone mass, bone markers, and hormones, including 1) bone mineral density (BMD) in total hip (0.1 +/- 2.1 vs. -2.4 +/- 2.5%), trochanter (0.2 +/- 3.3 vs. -3.3 +/- 3.1%), and intertrochanter (0.3 +/- 2.7 vs. -2.7 +/- .3.0%); 2) C-terminal telopeptide (12 +/- 35 vs. 101 +/- 79%) and osteocalcin (-5 +/- 15 vs. 66 +/- 61%); and 3) leptin (2 +/- 12 vs. -30 +/- 25%) and estradiol (0.1 +/- 14% vs. -14 +/- 21%) (all P < 0.05). Changes in weight (r = 0.55), bone markers (r = -0.54), and leptin (r = 0.61) correlated with changes in hip BMD (all P < 0.05).
  
  
  CONCLUSIONS
  Weight loss, even when combined with exercise, decreases hip BMD in obese older adults. It is not known whether the beneficial effects of weight loss and exercise on physical function lower the overall risk of falls and fractures, despite the decline in hip BMD.
authors: Division of Geriatrics and Nutritional Science, Center for Human Nutrition, Washington University School of Medicine, 4488 Forest Park Boulevard, St. Louis, MO 63108, USA. dvillare@im.wustl.edu
authors: Dennis T
authors: DT
authors: Villareal
authors: Krupa
authors: K
authors: Shah
authors: Marian R
authors: MR
authors: Banks
authors: David R
authors: DR
authors: Sinacore
authors: Samuel
authors: S
authors: Klein
mesh_terms: D000368:Aged; D001835:Body Weight / Q000502:physiology; D015519:Bone Density; D001862:Bone Resorption / Q000517:prevention & control; D001842:Bone and Bones / Q000378:metabolism* / Q000473:pathology*; D003131:Combined Modality Therapy; D004038:Diet, Reducing; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D009765:Obesity / Q000473:pathology / Q000628:therapy*; D009929:Organ Size / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology*