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Updated: Jul 14, 2026

Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice
Published on: November 27, 2019
FGF21: a missing link in the biology of fasting
1Department of Metabolic Disorders, Merck Research Laboratories, Rahway, NJ 07065, USA. marc_reitman@merck.com
Abstract:
A sufficient energy supply is essential for life; consequently, multiple mechanisms have evolved to ensure both energy availability and conservation during fasting and starvation. Two reports in this issue of Cell Metabolism (Badman et al., 2007; Inagaki et al., 2007) demonstrate that FGF21, a circulating protein produced in the liver in response to the PPARalpha transcription factor, is a "missing link" in the biology of fasting, inducing adipose tissue lipolysis, liver ketogenesis, and metabolic adaptation to the fasting state.
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