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Updated: Mar 22, 2026

A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood
Published on: April 28, 2016
Changes in hunger and fullness in relation to gut peptides before and after 8 weeks of alternate day fasting
Kristin K Hoddy1, Catherine Gibbons2, Cynthia M Kroeger1
1Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL, USA.
Background & Aims:
Alternate day fasting (ADF; 25% energy intake "fast day", alternated with an ad libitum intake "feed day") is effective for weight loss. Whether or not ADF modulates hunger, fullness and gut peptides in a way that enhances dietary compliance and weight loss, remains unknown. Accordingly, this study examined the effect of ADF on postprandial appetite ratings and gut peptides.
Methods:
Obese subjects (n = 59) participated in an 8-week ADF protocol where food was provided on the fast day.
Results:
Body weight decreased (P < 0.0001) by 3.9 ± 0.6 kg after 8 weeks of diet. Reductions (P < 0.05) in fat mass (-2.2 ± 0.2 kg), fat free mass (-1.4 ± 0.2 kg), visceral fat mass (-0.1 ± 0.1 kg), and resting metabolic rate (RMR; -104 ± 28 kcal/day) were also observed. Fasting leptin and insulin decreased (P < 0.05), while AUC ghrelin levels increased (P < 0.05). Despite these metabolic changes, there was no increase in subjective hunger by the end of the study. Furthermore, fullness and PYY increased (P < 0.05). Fat free mass and RMR were not related to hunger or ghrelin at any time point.
Conclusion:
These findings suggest that the absence of a compensatory increase in hunger in conjunction with an increase in sensations of fullness may contribute to the weight loss efficacy of an 8-week ADF regimen.
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