Research paper
Andriessen C, Doligkeit D, Moonen-Kornips E, Mensink M, Hesselink MKC, Hoeks J, Schrauwen P. The impact of prolonged fasting on 24h energy metabolism and its 24h rhythmicity in healthy, lean males: A randomized cross-over trial. Clinical Nutrition. 2023 Dec;42(12):2353-2362. doi: 10.1016/j.clnu.2023.10.010. PMID: 37862821.
Why we cite it
Provides the key counterpoint to the short-term fasting metabolic rate data (caf01, caf02): while short fasts increase or maintain REE, this study shows that extended fasting reduces 24h energy expenditure — by 8% across the 60h fast, the paper’s own summary figure, with the day-2 and day-3 pairs running 10.9% and 5.5% (corrected 2026-09-19 from ~11%, which is the day-2 figure presented as the 60-hour one). It also shows that the day-night rhythm of energy expenditure persisted independent of food intake — in 12 healthy, lean male volunteers, while substrate oxidation rhythms are food-driven — important for understanding circadian metabolic effects.
DOI: 10.1016/j.clnu.2023.10.010 · PubMed 37862821 · Publisher