Light has been understood to be the dominant zeitgeber for a long time now, in humans and the vast majority of other organisms, and this has not changed. Entra

Light has been understood to be the dominant zeitgeber for a long time now, in humans and the vast majority of other organisms, and this has not changed. Entrainment is also affected by temperature, eating, etc., but that does not in any way diminish the importance of light. https://www.ncbi.nlm.nih.gov/pubmed/23604485 https://www.ncbi.nlm.nih.gov/pubmed/23604485 E.g. meal timing might help you deal with jet lag, but remember that the primary problem in jet lag is the phase-shift of light in the first place.