About Circadian Rhythms

Circadian Rhythms are natural cycles that help our bodies control energy, mood, appetite and sleep. When our Circadian Rhythms get our of sync with nature our bodies suffer. Often times this may result in one or more Circadian Rhythm Sleep Disorders (CRSDs). Almost every person, at some time during the year, falls out of circadian balance and suffers from an anxiety, mood or sleep disorder. Fortunately, after years of research, scientists hae found the way to re-establish the body’s circadian balance.

The Rhythm of Nature

Much of nature is made up of rhythms and cycles. Common rhythms include the the twenty-four hour rotation of the earth, the twenty-eight day cycle of the moon’s orbit and the four seasons throughout the year. Like nature, our bodies also function in various rhythms. Some rhythms of the mind and body are tied to natural cycles. When functioning correctly, our bodies respond to these natural rhythms and cues to create an ideal balance. A great example is how the human circadian rhytm responds to morning light from the rising sun. Sunlight provides signals the body to produce serotonin, cortisol and various other hormones while also triggering neurotransmitters that it’s time to awaken. Blood pressure to increases and body temperature begins to rise, preparing you for a day of activity.

At dusk, the body receives another of nature’s cues and responds to the fading light at sunset and ultimately the darkness of the night sky. As the sun goes down the body produces and secretes the melatonin, blood pressure drops and the body prepares for and eventually falls asleep.

The Master Clock

The formal name for the medical science that studies circadian rhythms is chronobiology. Researchers have discovered that the human body is regulated by internal biological clocks synced to several internal rhythms that pace themselves hourly, daily, monthly, seasonally and even yearly.

Central to these timekeeping mechanisms of the body and mind is the Suprachaismatic Nucleus (SCN). The SCN is the body’s master clock and interacts with many regions of the brain to control circadian rhythms. The SCN is located inside the hypothalamus region of the brain and works with several time regulating genes. Together, the SCN and the timekeeping genes make up the master clock which governs many aspects of physiology and behavior by orchestrating the daily rhythms and cycles that control the ebb and flow of chemicals, hormones and neurotransmitters that determine sleep, wake, appetite, sex and other key functions of the body. Understanding this process is vital to learning how to regulate your circadian rhythms for a healthy mind and body.

Circadian Science

Circadian Rhythm studies can be dated as far back as the 19th century. However, the 1960’s ushered in a more focused studies and observations. Curt Paul Richter was an early pioneer in chronobiology, studying the hypothalamus. During his time as professor psychobiology at Johns Hopkins Medical School, Richter’s innovative concepts and methods were established for studying circadian rhythms in humans.

The word circadian is Latin and orgininates word circa meaning “approximately” and dian meaning “day”. The term was coined by Franz Halberg, a scientist at the University of Minnesota, when he published a paper in 1959 showing blood count varied according to a strict rhythm that was approximately one day. Additionally, Halberg discovered that circadian rhythms extended somewhat longer than a twenty-four hour period.

Chronobiology has since revealed that the body undergoes more than just blood count variations. In fact, the body makes numerous significant changes throughout the course of a single day.

Zeitgebers: The Body’s Way of Keeping Time

In order for us to reconcile the difference between natures exact twenty-four hour cycle and body’s longer than twenty-four hour internal circadian rhythm, nature has given us Zeitgebers (a German word that means “time givers”). Modern life and work schedules demand more flexibility with time. This has resulted in humans losing touch with the most valuable Zeitberger – the Sun. Busy lifestyles, ever increasing and varied work schedules, and artificial indoor lighting have altered the amount of sunlight our bodies receive, resulting in the regular disruption of our Circadian Rhythms.

Historically, people woke up at dawn, spent much of their day working outside or near a window, and retiring early in the evening or at the very least experiencing very low levels of candlelight before bed. The Feel Bright Light was developed to counteract the circadian disruptions created by this change in lifestyle life and help to reset and regulate the body’s natural rhythms for optimal health and well-being.