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Updated: Jul 11, 2026
09:29
Skeletal Muscle Gender Dimorphism from Proteomics
Published on: December 14, 2011
Sexual dimorphism of body composition
1Pediatric Nutrition Childhood Nutrition Research Centre, Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK. j.wells@ich.ucl.ac.uk
Best Practice & Research. Clinical Endocrinology & Metabolism
|September 19, 2007
Summary
Human body composition shows significant sex differences, particularly after puberty, driven by sex hormones. Adult males generally have more lean mass and less fat than females, with distinct tissue distributions.
Area of Science:
- Human physiology
- Endocrinology
- Anthropometry
Background:
- Sexual dimorphism in human body composition is observable from fetal development and becomes prominent during puberty.
- While birth differences exist in length and lean mass, puberty significantly shapes adult body composition due to differing pubertal transition durations and hormonal influences.
Purpose of the Study:
- To delineate the key sex differences in human body composition.
- To explore the hormonal underpinnings of these dimorphisms.
- To understand the implications for age-related changes and disorders of sex development.
Main Methods:
- Comparative analysis of body composition metrics between males and females across different life stages.
- Examination of the role of sex steroid hormones, particularly estrogen, in mediating these differences.
- Review of body composition in individuals with disorders of sex development.
Main Results:
- Adult males exhibit greater lean mass, mineral mass, and arm muscle mass, with reduced limb fat compared to females, even after adjusting for height.
- Females show a more peripheral fat distribution in early adulthood, which shifts towards an android pattern with age, parity, and menopause.
- Estrogen plays a critical role in female fat distribution and bone development, influencing osteoporosis risk.
Conclusions:
- Sex differences in body composition are primarily driven by sex steroid hormones during pubertal development.
- Hormonal regulation significantly impacts tissue distribution, bone health, and age-related body composition changes.
- Disorders of sex development highlight the crucial role of hormonal mechanisms in maintaining normal body composition.
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