Biological Clock Circadian Rhythm

Three scientists have just received Nobel Prize in medicine for proving scientifically something we knew all along. The scientists share the 1.1 million dollar prize for proving that we really do have a biological clock. The fact that you are alert at certain times and sleepy at others is not just in your head.

In 1984 they sequenced the “period gene” which others had discovered in fruit flies in 1971. The gene controls the circadian rhythm which regulates the daily sleep and wake patterns of all creatures, including humans. Following up on that work, in 1998 they found that the gene encodes a protein called PER. The PER levels build up at night and drop during the day. This discovery enables scientists to understand the molecular makeup of the biological clock.

Learning more about our biological clock leads to some useful understandings, including when is the best time to take certain medications. It also relates to shift work, jet-lag, and school classroom times. The understanding of circadian rhythms can be incorporated into practical medicine and the body’s production of melatonin, a hormone that prepares us for sleep.

A group of sleep researchers a few years ago did some research on biological clocks. They sent a group of volunteers on a tent-camping trip to the Colorado Rockies. They found that people who work indoors where they are not exposed to outdoor light may need to have their biological clocks reset. When people are indoors during the day and exposed to electric lights at night, their clock can become out of sync. Exposure to strong artificial light at night can delay our master clock. That delays the production of melatonin at night, and then the melatonin level is still high in the morning when it’s time to get up.

The campers were only allowed to use campfires for light and no cellphones or flashlights. After spending a week away from artificial light and exposed to more daylight, the volunteers fell asleep earlier and woke up earlier. Their melatonin levels rose earlier in the evening and dropped earlier in the morning.

The recommendation of the researchers was to start your day with a morning walk and when you have to be inside open the shades to get exposure to some sunlight. You may find that you will sleep better and wake up more refreshed.

“And God said, ‘Let there be lights in the expanse of the sky to separate the day from the night’…God set them in the expanse of the sky to give light on the earth, to govern the day and the night, and to separate light from darkness. And God saw that it was good” (Genesis 1:14, 17).
–Roland Earnst © 2017