Get Enough Light? Probably Not & Why You Should


All of us were born with a unique internal rhythm called the circadian clock. Chronobiology, a new area of scientific research, studies these internal rhythms.

Chronobiology has already revealed that our biological rhythms are more complex than most of us realize.

Fighting the Clock

Your circadian (biological) clock, which takes up only a bit of your brain, has connections to your internal and external environments. It influences your interaction with the world such as your waking time, mental alertness, and mood. Simultaneously, the earth’s daily cycle of light and dark influences your biological patterns.

Information exchanged between your inner clock and the outer world creates a feedback loop. The loop keeps your internal rhythms in sync with nature’s cycles. Problems occur when the feedback loop is disrupted and inner rhythms are no longer working in cooperation with the outer ones.

The Role of Light

It is possible that not getting enough light each day is responsible not just for seasonal affective disorder (SAD) but for other illnesses as well. Like many people, you might spend most of your time indoors and not get a healthy dose of light each day, even during summer months. If so, you may be interested in chronotherapy.

Re-Syncing Your Inner Clock

Chronotherapy is about helping people re-sync their inner clocks with the cycle of day and night, and many of us may need re-syncing. Our modern urban and suburban lifestyles can easily slow down or speed up our inner timer, causing problems.

Aside from being indoors too much, daylight savings time skews people's biological rhythms, as does looking at bright computer screens into the evening. Having a TV on in the bedroom, or even a streetlamp that brightens the room, will affect the timing of our body’s cycles.

For instance, your inner clock is responsible for telling your pineal gland when it should manufacture the sleepy-time hormone melatonin. This is the hormone that allows you to nod off at night. However, if your circadian clock is out of step with nature’s clock, you may become sleepy when you need to be alert, or awake when you need to sleep.

Fortunately, there are steps anyone can take to add more light to their day.

Keeping the Inner and Outer Clocks in Sync

  1. Taper off the level of light you get as bedtime approaches. If you use a computer late at night consider using some type of filter that dims the computer.
  2. Eliminate rogue light when you are sleeping. If necessary, use thick curtains or light-blocking shades.
  3. Consider using a dawn simulator that slowly increases the bedroom’s light when it’s time to awaken.
  4. If you use night lights, make sure they are amber. Amber will not throw off your circadian clock.
  5. Get as much natural sunlight as you can during the day.
  6. Keep your home or work area brightly lit during daylight hours.

The information presented here barely scratches the surface of chronobiology, but if you have problems with falling asleep, low energy, grogginess in the morning, or feel depressed, this is an area of science and therapy you may want to learn more about.

Source: Terman, Michael, PhD., and McMahan, Ian, PhD., Chronotherapy, Resetting Your Inner Clock to Boost Mood, Alertness, and Quality Sleep, The Penguin Group, 2012.

Photo by John Nyboer


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