A time to fast, a time to feast: the crosstalk between metabolism and the circadian clock

Mol Cells. 2009 Aug 31;28(2):75-80. doi: 10.1007/s10059-009-0113-0. Epub 2009 Aug 20.


The cyclic environmental conditions brought about by the 24 h rotation of the earth have allowed the evolution of endogenous circadian clocks that control the temporal alignment of behaviour and physiology, including the uptake and processing of nutrients. Both metabolic and circadian regulatory systems are built upon a complex feedback network connecting centres of the central nervous system and different peripheral tissues. Emerging evidence suggests that circadian clock function is closely linked to metabolic homeostasis and that rhythm disruption can contribute to the development of metabolic disease. At the same time, metabolic processes feed back into the circadian clock, affecting clock gene expression and timing of behaviour. In this review, we summarize the experimental evidence for this bimodal interaction, with a focus on the molecular mechanisms mediating this exchange, and outline the implications for clock-based and metabolic diseases.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Biological Clocks / physiology*
  • CLOCK Proteins / genetics
  • CLOCK Proteins / metabolism
  • Circadian Rhythm / physiology*
  • Energy Metabolism / physiology*
  • Gene Expression Regulation
  • Homeostasis
  • Humans
  • Period Circadian Proteins / genetics
  • Period Circadian Proteins / metabolism
  • Time Factors


  • PER2 protein, human
  • Period Circadian Proteins
  • CLOCK Proteins
  • CLOCK protein, human