Normal acquisition and loss of bone mass
1US Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, Tex. 77030, USA. sabrams@bcm.tmc.edu
Hormone Research
|December 13, 2003
Summary
Bone mass changes throughout life, from fetal development and infancy to puberty and adulthood. Hormonal shifts during puberty and perimenopause significantly impact bone density and calcium absorption.
Area of Science:
- Bone biology and physiology
- Human development
- Endocrinology
Background:
- Bone mass accumulation and loss follow predictable patterns throughout the human lifespan.
- These changes are influenced by physiological and genetic factors, marking distinct life stages.
Purpose of the Study:
- To outline the natural trajectory of bone mass changes across different life periods.
- To highlight key physiological events influencing bone mass accumulation and loss.
Main Methods:
- Review of established knowledge on bone metabolism and calcium dynamics.
- Analysis of physiological changes during pregnancy, infancy, puberty, adulthood, and perimenopause.
Main Results:
- Fetal bone mass accrual is rapid during the third trimester.
- Infancy involves maternal calcium transfer and subsequent bone replenishment.
- Puberty sees a significant bone mass increase, with peak deposition rates in females before menarche.
- Peak bone mass is typically reached by age 25-30.
- Estrogen decline during perimenopause leads to increased bone resorption and loss.
Conclusions:
- Bone mass is dynamically regulated throughout life, with critical periods of accumulation and loss.
- Understanding these patterns is essential for maintaining skeletal health across the lifespan.
- Hormonal changes, particularly estrogen levels, play a crucial role in adult bone maintenance.
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