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Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice
Published on: November 27, 2019
Energy intake in weight-reduced humans.
Michael Rosenbaum1, Harry R Kissileff, Laurel E S Mayer
1Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, NY, USA. mr475@columbia.edu
Brain Research
|July 3, 2010
Summary
Sustaining weight loss is challenging due to decreased energy expenditure and increased hunger. Biological factors, including the hormone leptin, actively oppose reduced body weight maintenance.
Area of Science:
- Metabolism and Endocrinology
- Obesity Research
- Neuroscience of Appetite Regulation
Background:
- Weight loss maintenance is significantly harder than initial weight loss.
- Reduced body weight is accompanied by energy expenditure lower than predicted by body composition.
- High recidivism rates suggest biological factors oppose sustained weight loss.
Purpose of the Study:
- To explain the biological mechanisms hindering long-term weight loss maintenance.
- To investigate the interplay between energy expenditure, intake, and hormonal regulation.
- To identify key factors contributing to the high rate of weight regain.
Main Methods:
- Analysis of energy expenditure changes post-weight loss.
- Evaluation of energy intake regulation and perception of satiety.
- Examination of neuronal signaling pathways involved in appetite control.
- Investigation of the role of adipocyte-derived hormones, particularly leptin.
Main Results:
- Energy expenditure decreases disproportionately after weight loss.
- Energy intake increases during weight maintenance, not decreasing as expected.
- Reduced satiation and altered neuronal responses to food contribute to weight regain.
- The hormone leptin plays a significant role in mediating biological opposition to sustained weight loss.
Conclusions:
- Biological opposition, mediated by leptin and altered appetite signaling, makes sustained weight loss difficult.
- The body actively defends a higher body fat threshold.
- Understanding these mechanisms is crucial for developing effective weight management strategies.
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