New Scientist stops the clock with timely news about skin. Apparently, skin is pretty deep – it’s somehow tied to the brain as part of our internal clock:
“Knowing that skin clocks ‘tick’ in the same way as brain clocks provides a nice tool to address whether a person is likely to be an early or late riser,” says Russell Foster, a circadian rhythm specialist at the University of Oxford, UK.
“It’s remarkable that measures from the skin allow predictions of brain-driven behaviour,” he adds.