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Updated: Jun 20, 2026
09:48
Differentiated Mouse Adipocytes in Primary Culture: A Model of Insulin Resistance
Published on: February 17, 2023
Evolution, body composition, insulin receptor competition, and insulin resistance
S Boyd Eaton1, Loren Cordain, Phillip B Sparling
1Department of Anthropology, Emory University, 2887 Howell Mill NW, Atlanta, GA 30327, USA. sboydeaton@comcast.net
Preventive Medicine
|August 19, 2009
Summary
Modern humans have abnormal body composition, leading to an imbalance in insulin receptors. This shift from evolutionary norms contributes to widespread insulin resistance and the type 2 diabetes epidemic.
Area of Science:
- Metabolic Health
- Evolutionary Medicine
- Human Physiology
Background:
- Modern lifestyles have led to unprecedented levels of human adiposity (excess body fat) and sarcopenia (age-related muscle loss).
- This abnormal body composition significantly disrupts the body's normal balance of insulin receptors.
Purpose of the Study:
- To investigate the relationship between altered body composition and the development of insulin resistance.
- To explore how changes in insulin receptor distribution contribute to metabolic dysfunction.
Main Methods:
- The study conceptually analyzes the balance of insulin receptors in adipose tissue, liver, and muscle.
- It compares current human insulin receptor distribution to evolutionary norms.
- The impact of receptor distribution on glucose clearance from the blood is examined.
Main Results:
- Current human body composition shows an excess of insulin receptors in adipocytes (fat cells) and the liver, and a deficit in myocytes (muscle cells), compared to evolutionary standards.
- This imbalance means fewer glucose molecules are cleared from the blood when insulin binds to fat cell receptors versus muscle cell receptors.
- This populational insulin receptor imbalance correlates with the rise in insulin resistance and type 2 diabetes.
Conclusions:
- An evolutionary perspective on body composition and insulin receptor imbalance offers a compelling explanation for carbohydrate metabolism issues.
- Understanding this imbalance can improve public acceptance of physical activity recommendations to combat insulin resistance.
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