Our ‘Food Clock’
By Dr Zafar M. Iqbal
TCCI, Chicago, IL
Holidays are over, and a New Year is now here.
We survived the holiday sale come-ons and another nerve-racking shopping for those already on the list as well as the last minute add-ons. And we survived the festive dinners, family get-togethers and office parties. Little heavier perhaps, which is what the resolutions are for the New Year, or at least for the first couple of weeks.
An old battle that demands an ever-increasing will power as we age! If not careful moderation in the Holiday intake, it is the determination later to stick to the resolutions we religiously make, over our excesses in the recent past, to start the next year on a better, at least a saner foot.
To the graveyard shifts, an irrepressible sweet-tooth and late-night ‘fridge raids that we wouldn’t want to admit, you may want to add the Holidays as another culprit in upsetting what is called our ‘food clock’. This charge is not made without some scientific evidence from research at University of California, San Francisco (UCSF), published in the Proceedings of National Academy of Sciences, December, 2012.
Food Clock is actually a group of molecules and genes, known as the ‘food-entrainable oscillator’, which helps keep our metabolism functioning without problems. UCSF researchers found that this ‘food clock’, if and when disturbed or desynchronized, needs to be re-set. In re-setting this clock, a critical factor they find is a protein called PCKy.
This research in laboratory mice showed that when animals are given food during their normal sleeping hours, they will not only consume that, despite the hour, but if this unusual schedule is kept up over a period, the animals will wake up at a time when they should be sleeping, and look for food. Eating at the ‘wrong’ time disturbs the subtle molecular interactions among the participants, which will then desynchronize the food clock. At a mechanistic level, the researchers found that the PCKy protein binds to another molecule, BMAL1 to stabilize it and help appropriate shift time in the food clock. Mice that lack the PCKy gene do not respond to the new eating time and would even sleep through it.
Food clock, like other biological clocks, is based on complex interactions among multiple genes that are turned ‘on’ or ‘off’ in a synchronized, time-dependent manner. Biological clocks in different organisms are in control of ‘Circadian oscillator’ which helps orchestrate their various biological processes over a 24-hour cycle. A tiny center in the brain, ‘superchiasmatic nucleus’, normally controls various clocks and their individual components, but the food clock, on the other hand, is controlled by multiple sites, including genes involved in absorption of nutrients, spread via bloodstream to various organs. Though little is known for certain how exactly this clock works genetically, the scientists believe that it is even trained to anticipate the meal times.
The lead scientist of this team, Dr. Louis Ptacek, believes that the molecular pathology of diabetes, obesity and other metabolic syndromes may be traced back to some type of desynchronization of the food clock.