Strong Sleep, Again

The Circadian Rhythm Is A Weapon Against Disease

Health is greatly limited — or improved — by the quality of the circadian rhythm..

Upgrading the circadian rhythm could be the most important area to focus on to improve health — especially in chronic illness and aging.

MENU

1 — Melatonin, The Hormone Of Sleep
2 — The Melatonin Cycle
3 — Light Cycles Control Melatonin
4 — Darkness Raises Melatonin
5 — Modern Melatonin Cycles Are Broken
6 — The Brain’s “Clock”
7 — The SCN Knows Time Of Day
8 — Bright Light Lowers Melatonin
9 — Brightness & Color
10 — Good Light & Bad Light
11 — The Day/Night Light Cycle
12 — Color Temperature
13 — Sunlight’s Changing Color Temperature
14 — Meal Timing Affects Circadian Rhythm
15 — Other Factors

“One of the defining characteristics of life in the modern world is the altered patterns of light and dark in the built environment made possible by use of electric power.”

Environmental Health Perspectives, September 2007 issue

NETFLIX CEO Reed Hastings:

“You get a show or a movie you’re really dying to watch and you end up staying up late at night, so we actually compete with sleep,” Hastings said, adding triumphantly, “And we’re winning!” (Nov 3, 2017)

77% Of Brits Fail To Wake Up Rested & Refreshed.

China is the most sleep-medicated country in the world.

79% Of Americans Are Sleep Deprived

The average American only sleeps 6.8 hours per night.


1

Melatonin: The Hormone Of Sleep

The human body can’t sleep without melatonin rising at night.

When Melatonin Rises, The Body Feels Sleepy

These kids are able to fall asleep ANYWHERE! 💤

These kids are able to fall asleep ANYWHERE! 💤

Posted by Daily Mail Moms on Wednesday, October 3, 2018

Melatonin is the primary component that tells the body it’s time for sleep. When melatonin rises, it may not be possible to stay awake.

This can observed when children fall asleep — anytime, anywhere. This is robust melatonin in action.

When people struggle to fall asleep and stay asleep, this powerful release of melatonin is not occurring optimally.

Rising melatonin is essential for the body to sleep.

What Causes Melatonin To Rise?

Darkness is the main component that causes melatonin to rise.

2

Healthy Melatonin Cycles

High By Night, Low By Day

Melatonin must rise at night to facilitate sleep.

For this to happen, melatonin must be low throughout the day.

High Melatonin

Melatonin — Rises After Dark

Melatonin rises at nighttime, just before bed — to make you fall asleep (and want to fall asleep).

Low Melatonin

Melatonin — Drops In The Morning

Melatonin falls just before you wake up. If melatonin stayed high, you’d keep sleeping. The bright light of the morning tells the brain to lower melatonin levels.

This cycle should align perfectly with natural sunlight cycles: when the sun is up –> melatonin is down.

What keeps melatonin low during the day?

3

Light Controls Melatonin

Light Lowers Melatonin

When light enters the eyes and hits the photoreceptors on the skin, melatonin levels drop instantly.

When melatonin falls, humans feel alert and awake.

4

Darkness Raises Melatonin

Less Light Means More Melatonin

Every time the body perceives darkness, melatonin begins to rise.

Over time, the repeated daily and nightly cycles of light and dark “entrain” the brain to know the time of day — and, therefore, the level that melatonin should be produced.

5

The Broken Melatonin Cycle

Melatonin Cycles Are Weakening

Modern lifestyles undermine the melatonin cycle at every turn, and from every angle.

Things have gotten much, much worse since 2005.

Low Melatonin, Poor Sleep Quality

When evening melatonin production is harmed, sleep quality suffers.

Even if a person falls asleep quickly and sleeps through the night, that sleep is less restorative and healing.

In a 2010 study, normal room light in the evening harmed the melatonin response all night.

Translation: “Normal” light before bed lowers your melatonin ALL night.

“Compared with dim light, exposure to room light before bedtime suppressed melatonin, resulting in a later melatonin onset in 99.0% of individuals and shortening melatonin duration by about 90 min.”

https://www.ncbi.nlm.nih.gov/pubmed/21193540

These findings indicate that room light exerts a profound suppressive effect on melatonin levels and shortens the body’s internal representation of night duration. Hence, chronically exposing oneself to electrical lighting in the late evening disrupts melatonin signaling and could therefore potentially impact sleep, thermoregulation, blood pressure, and glucose homeostasis.

https://www.ncbi.nlm.nih.gov/pubmed/21193540
6

The Brain’s Clock

The Suprachiasmatic Nucleus (SCN).

The “SCN” Controls Melatonin

The SCN is the brain’s clock.

It tells the brain what time of day it is. 24/7 — it works to keep the entire body functioning on schedule and on time.

When the time is right, the SCN tells the pineal gland when to start producing melatonin — and when to stop producing melatonin.

The SCN interpets the intensity and wavelengths of light that enter the eye and uses them to determine the time of day or night. 

The light that hits the eyes is highly responsible for the SCN’s ability to know when it’s daytime and nighttime.

The SCN then tells the pineal gland how much melatonin to produce. The effect is rapid, with melatonin levels rising and falling quickly in response to light stimuli — or the lack thereof.

8

Bright Light Before Bed

STUDY: “Room Light” Before Bed Lowered Melatonin In 99% Of Individuals

Researchers studied 116 test subjects, exposing them to either “normal” room light or dim light in the hours prior to bedtime.

The results were clear: 99% of test subjects experienced a “profound suppressive effect on melatonin.”

This melatonin reduction delayed the body’s perceived window for sleep.

What’s more, when room light was present during sleeping hours, melatonin production was reduced by greater than 50% (in 85% of subjects).

“These findings indicate that room light exerts a profound suppressive effect on melatonin levels and shortens the body’s internal representation of night duration.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3047226/

9

Brightness & Color

Blue Is Bad At Night

Blue light lowers melatonin much more than red light — even 100 times more than red light.

By contrast, red light — even when extremely bright — will only lower melatonin a small amount. Weak, dim red light will have almost no impact on melatonin levels.

Even an incredibly tiny amount of blue light can significantly lower melatonin levels in the brain.



Blue wavelengths… seem to be the most disruptive at night. And the proliferation of electronics with screens, as well as energy-efficient lighting, is increasing our exposure to blue wavelengths, especially after sundown.

https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side

Green Light Does Have A Moderate Effect On Melatonin

Green light lowers melatonin at about half the rate of blue light — which is way more than red light.

“Our results suggest that we have to consider not only blue light when predicting the effects of light on our circadian rhythms, hormones and alertness, but also other visible wavelengths such as green light.” 

Steven Lockley, PhD

Virtually zero effect
on melatonin.

Moderate effect
on melatonin.

Powerful effect
on melatonin.

10

Good Light & Bad Light

Light that affects the melatonin cycle.

Good Light

Good light reinforces your melatonin cycle –making it stronger.

1) Sunlight

  • Sunlight is the best form of “good” light.  It is bright, its color temperature changes perfectly to guide the brain’s melatonin levels throughout the day.

2) Incandescent Bulbs

  • Bright incandescent lamps are the best source of healthy light during the day. Halogens are just as good. These bulbs can provide moderate amounts of visible light in balanced ratios, helping the circadian rhythm. They are also safer than LEDs and fluorescents.

Bad Light

Bad light disrupts your melatonin cycle — making it weaker.

1) Dark Rooms During The Day

  • A dark room — in daytime –mimics nighttime and tells your brain to immediately make more melatonin.

2) Bright Rooms At Night

  • Being close to fluorescent and LED lighting after sundown, or looking at bright screens at night tells your brain to “wake up” — and reduce its production of melatonin.

*Technically, fluorescent and LED lighting is unhealthy during the day, as well, but for reasons other than the circadian rhythm.


11

The Day/Night Light Cycle

(1) Bright Daytime Light

Low daytime melatonin means more evening melatonin.

It’s unwise to spend all day in a dimly-lit room. This teaches melatonin levels to rise during the day — even if it’s sunny outside.

Bright daytime light not only immediately suppresses melatonin — it actually causes melatonin to rise at the proper time in the evening. Sunlight tells the brain exactly what time it is, boosting morning serotonin so that it can be later converted to melatonin. When night comes, the brain is ready to convert serotonin to melatonin for sleep.

The brighter the daytime light — the better the sleep that night.

Morning sunlight is the premier source and timing of light. The more morning sunlight one gets, the better — though even a 2-3 minute does is powerful and effective.

When people are exposed to sunlight or very bright artificial light in the morning, their nocturnal melatonin production occurs sooner, and they enter into sleep more easily at night…

The melatonin rhythm phase advancement caused by exposure to bright morning light has been effective against insomnia, premenstrual syndrome, and seasonal affective disorder (SAD).

www.ncbi.nlm.nih.gov/pmc/articles/PMC2290997/

Morning light has profound benefits for the circadian rhythm, and then receiving a bright-light stimulus throughout the day continuously informs the brain that it’s daytime.

In fact, sunlight’s color temperature constantly shifts throughout the day, getting white/bluer (with more UV) all morning. In the afternoon, the UV and blue continuously drop, leaving a warmer, redder light.

This continually — and perfectly — informs the SCN about the time of day.

(2) Darkness At Night

Complete darkness at night allows melatonin levels to rise optimally.

Optimally, we reduce exposure to bright and blue light several hours prior to bedtime.

For extreme circadian retraining, it can even be helpful to spend an hour in complete darkness prior to bedtime.

The further the effort toward evening darkness, the deeper the benefits, and the more likely the circadian rhythm will be properly restored and maintained.

The darker the dark? Higher melatonin levels.

After years of undermining it, a strong circadian rhythm often takes weeks and months to develop. Once strong, it can become robust and bounce back more and more quickly.

The benefits of circadian rhythm work can begin to be noticed in as little as a few days to a few weeks.
12

Color Temperature

Every light source has a “color temperature” — rated in Kelvins.

High In K(elvin)

Color temperature describes the ratio of blue to red.

The higher the Kelvin, the more blue. The lower the Kelvin, the more red.

Source: https://www.westinghouselighting.com/color-temperature.aspx

Above 4000K is very high color temperature — for the health of the eyes and for evening lighting.

Various Light Sources — Kelvin Rating

Candle Flame

1850K

Sunset / Sunrise

1850K

Incandescent Bulb

2400K

Fluorescent Bulb

5000K

Screens

Screens are 6500-9500 Kelvin.

This means they are terrible for eye health as well as sleep.

WARM LIGHT
(Low Kelvin number)

Red wavelengths are dominant. Light looks more red, orange, or yellow. 

“COLD LIGHT”
(High Kelvin number)

Blue wavelengths are dominant. Light looks more white, or even blue. 

White light is extremely high in blue wavelengths.

White light is rich in blue light, and deficient in red light.
13

Sunlight’s Changing Color Temperature

Sunlight’s Colors

With exception of solar flares and subtle fluctuates that don’t affect humans day-to-day, the sun actually produces the same light non-stop.

However, the light that reaches the ground is very different as the day, season, latitude, and altitude change.

In the morning, nearly all blue light is filtered out by particles in the atmosphere, leaving the rich reds and oranges to reach the ground.

The atmosphere absorbs shorter wavelengths (like blue and UV). When the sun is low in the sky, those short frequencies are filtered out.

The Day Begins & Ends In Red Light

Sunrise and sunset both lack blue light.

The first and last few hours of each day have a unique, warm light signature. This warm light signals for your brain to transition to the next phase of your circadian rhythm.

Sunlight’s naturally changing color temperature (controlled by the angle of the sun) perfectly sets the brain up for powerful sleep cycles.

Morning sunlight has virtually zero blue wavelengths — hence it is warm and red.

By contrast, solar noon is rich in blue light — signalling the brain: “It is mid-day!”

As daytime sunlight retreats, the brain knows nighttime is approaching. Melatonin in preparation for deep, restorative sleep.


14

Movement & Meal Timing

Movement

Movement seems to clearly signal “daytime” to the brain.

Therefore, to further synchronize the circadian rhythm, daily movement is an important variable.

Gentle, “Zone 2” exercise is perfect for sleep: Not too intense, just enough to get the blood pumping, burn glutamate, and lower melatonin.

Exercise and movement suppress melatonin secretion. Therefore, it’s best to exercise during the day — while the sun is up — rather than later in the evening.

Morning is the optimal time to exercise, but midafternoon is fine as well.

For many, if late in the evening is the only viable option, it may be best to go ahead and exercise in the evening. In these (hopefully rare) situations, late evening exercise that is very intense may be best for melatonin levels.

Along with strengthening the circadian rhythm, movement also improves gut health, the lymph system, and burns up glutamate in the brain & body — allowing you to relax when you lay down at night.

Meal Timing

When you eat really, really matters for quality sleep.

It’s not necessary to be perfect with meal timing, but the earlier you eat your meals, the better for sleep and the circadian rhythm.

Getting these steps wrong can seriously impact the quality of your sleep — and your health.

Light tells the brain it’s daytime — and so do eating and movement. Darkness tells the body it’s nighttime.

It’s important to get the right amount of exercise — and then eat enough calories to support that movement. Whenever possible, great care should be taken to ensure meals are eaten a little early rather than a little late.

Coming up in the Sleep section… This page is for members.  We’d love for you to be one!
 

Eating Early Helps The Circadian Rhythm

Eat a real breakfast within a half hour of waking.

Be finished eating for the day — fully supplied with sufficient calories to last the night — by a reasonable time in the evening.


15

Other Factors

There are certainly other factors that are important for the circadian rhythm. Those other factors will be discussed in the following sections.

If one’s light exposure is poor, every other step taken toward health will be less effective.

16

The Perfect Sleep Rhythm

There’s An Optimal Sleep/Wake Rhythm

It doesn’t take long — once after A) trying things for oneself, B) digging into the evidence, and C) working with people — to realize that there’s an optimal time to sleep and rise.

Perhaps for some, an 11:30 PM bedtime would be a major improvement. If that’s the next step to make, it will be a beneficial one. Moving a bedtime from 2:00 AM to 11:30 PM is an incredibly powerful shift.

A similar improvement is possible when moving the bedtime from 11:30 PM to 9:30 PM.

Imagine how great life can be, consistenly fast asleep before 10:00 PM most nights.

The key to an early bedtime will always be an early morning.

Don’t Think You Can Get There?

Perhaps you’re worried about mid-night wakings, or that you’ll lie in bed for hours. I know, I’ve been there, too. My sleep was spectacularly atrocious for the first 15 years of my adult life. Then, I figured it out, and these are steps that made the difference.

I never “take” anything to sleep now. I have confidence — every single night — that I can and will fall asleep, and wake up refreshed.

I changed my life, and it all started with my circadian rhythm.

…You can, too.

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