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Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Bone loss accompanying diet-induced or exercise-induced weight loss: a randomised controlled study
J E Pritchard1, C A Nowson, J D Wark
1Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia. Jan_Pritchard.Physiology@muwaye.unimelb.edu.au
Summary
Dieting caused bone mass loss, while exercise did not significantly impact bone mineral density or content in overweight men. Fat loss correlated with bone changes in both groups.
Area of Science:
- Human physiology
- Bone metabolism
- Weight management
Background:
- Weight loss interventions, such as diet and exercise, are common strategies for improving health in overweight individuals.
- Understanding the differential effects of these interventions on body composition, including bone tissue, is crucial for public health.
- Previous research has yielded mixed results regarding the impact of weight loss on bone mineral density (BMD) and bone mineral content (BMC).
Purpose of the Study:
- To compare the effects of a low-fat diet versus moderate aerobic exercise on changes in bone mineral content (BMC), bone mineral density (BMD), fat mass, and lean tissue in overweight men.
- To investigate the relationship between fat loss and changes in BMC in response to diet and exercise interventions.
Main Methods:
- A prospective, randomized, controlled, long-term worksite study.
- Involved 66 overweight men (mean age 43.4 years, BMI 29.0 kg/m2).
- Interventions included a low-fat diet or moderate aerobic exercise; body weight, lean mass, fat mass, BMC, and BMD were measured using dual-energy X-ray absorptiometry.
Main Results:
- Dieters experienced a 1.4% decrease in BMC and 1.5% decrease in BMD, with an average weight loss of 6.4 kg.
- Exercisers (2.6 kg weight loss) and control subjects (no weight change) showed no significant changes in BMC or BMD.
- Changes in BMC were positively correlated with fat loss in both dieters (11.7 g BMC/kg fat loss) and exercisers (11.4 g BMC change/kg fat loss).
Conclusions:
- Diet-induced weight loss leads to a loss of bone mineral content (BMC), primarily reflecting the loss of overall weight and body fat.
- Exercise interventions, in this study, did not result in significant changes in BMC or BMD despite some weight loss.
- Further research is needed to determine if equivalent weight loss achieved through exercise would result in similar BMC loss as observed with diet-induced weight loss.
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