Longevity & Aging · Metabolic & Cardiometabolic
peripheral organ circadian clocks liver gut muscle are-entrained-primarily-by food timing rather than light
In plain terms: For organs like the liver, is meal timing a stronger clock-setter than light?
True under imposed time-restricted feeding, but a key independent study shows normal non-restricted eating patterns barely shift peripheral clocks — so food-is-dominant-zeitgeber holds mainly under artificial fasting regimens.
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Animal studies (Animal)
How the studies fall
The evidence (2)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Xie 2020 · BMC Biol | animal | contradicts | high | Independent (Butler/OHSU) counter-study: under naturalistic feeding, normal food-intake patterns have LITTLE synchronizing effect on liver/kidney/gland clocks — only non-physiologic long-fast TRF entrains them. |
| Sheward 2007 · J Neurosci | animal | supports | moderate | Independent (Edinburgh): restricted feeding synchronizes hepatic clock-gene rhythms even in SCN-clock-deficient mice, showing food can act as an effective peripheral zeitgeber. |
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