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Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice
Published on: November 27, 2019
An isocaloric increase of eating episodes in the morning contributes to decrease energy intake at lunch in lean men.
Xavier Allirot1, Laure Saulais, Kevin Seyssel
1Centre de Recherche de l'Institut Paul Bocuse, Château du Vivier, 69130 Ecully, France. xavier.allirot@institutpaulbocuse.com
Physiology & Behavior
|January 22, 2013
Summary
Increasing eating frequency improved appetite and reduced hunger in lean men by increasing glucagon-like peptide-1 (GLP-1) and decreasing ghrelin. However, it also reduced diet-induced thermogenesis and inhibited lipolysis.
Area of Science:
- Metabolism and Nutrition
- Human Physiology
- Appetite Regulation
Background:
- The impact of varying eating frequencies on human health remains incompletely understood.
- Previous research offers limited insight into the short-term metabolic and appetite responses to altered meal timing.
Purpose of the Study:
- To investigate the short-term effects of increasing eating frequency on appetite and metabolism in normal-weight men.
- To assess hormonal, metabolic, and behavioral responses to different breakfast consumption patterns.
Main Methods:
- A controlled study involving 20 normal-weight men comparing single (F1) versus four (F4) isocaloric breakfast episodes.
- Measurement of appetite ratings, ad libitum buffet meal intake, and hormonal profiles (ghrelin, GLP-1, insulin, NEFA).
- Analysis of substrate oxidation via indirect calorimetry and assessment of diet-induced thermogenesis.
Main Results:
- Increased eating frequency (F4) led to higher GLP-1 and lower ghrelin concentrations, with reduced hunger ratings.
- A trend towards lower energy intake at a subsequent buffet meal was observed after F4, primarily due to reduced lipid consumption.
- Differences in glucose, insulin, and NEFA kinetics were noted, with lower insulin and NEFA area under the curve in F4. Diet-induced thermogenesis was reduced.
Conclusions:
- Increasing eating frequency demonstrates short-term benefits for appetite regulation in lean men, supported by subjective, physiological, and behavioral data.
- The absence of an inter-prandial fast with increased eating frequency was associated with inhibited lipolysis and decreased energy expenditure.
- Further research is needed to fully elucidate the long-term metabolic consequences of altered eating frequencies.
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