Lifestyle & Belief

Gluttonous holiday eating can reset body's natural "food clock"


Traditional, home-made Christmas cookies lie on plates in a household on December 21, 2010 in Berlin, Germany. Christmas cookies are an intrinsic part of Central European Christmas tradition and are usually baked at home according to recipes passed down through generations.


Sean Gallup

We already know that the human brain can keep track of time with an internal clock, as new evidence showed in October— a elegant system that incorporates individual brain circuits.

But the brain also regulates when we feel hungry and begin to seek out food, a natural, useful rhythm that can be thrown off by all those bountiful holiday calories, University of California San Francisco researchers claim, in an article recently published in the Proceedings of the National Academy of Sciences journal.

Read more from GlobalPost: Brain keeps its own internal clock, says new study

How does this work? UCSF researchers pinpointed a special protein called PKCγ, which binds to a molecule called BMAL, "setting" our internal food clock, or causing us to engage in "food entrainment," or anticipation.

Translation: if you generally wake up early in the morning because you're hungry and eagerly anticipating pouring out your a.m. Lucky Charms and soy milk, you're engaging in food entrainment, just like the aforementioned laboratory mice.

However, this setting of circadian rhythms can be thrown off by excess eating or eating at odd times, said the researchers—and mice that lacked the PKCy gene appeared to be unable to regulate their meal times at all.

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This could theoretically help explain the unhealthy eating habits of the obese, diabetics, and humans suffering from metabolic issues, speculates the UCSF report on the new findings.

“Understanding the molecular mechanism of how eating at the “wrong” time of the day de-synchronizes the clocks in our body can facilitate the development of better treatments for disorders associated with night-eating syndrome, shift work and jet lag,” said Louis Ptacek, a professor of neurology at UCSF of the research.

As for the rest of us? Beware messing up your internal "food" clock over the holidays. And maybe lay off the cookies.