Blue Light, Depression & Anxiety

A Harvard study identified preliminary results that link blue light to diabetes and possibly obesity.

Blue Light At The Beach

The researchers put ten people on a schedule that gradually shifted the timing of their circadian rhythms similar to what occurs when you look at a screen or mobile phone. The test subject’s blood sugar levels increased, placing them into a pre-diabetic state. Their levels of leptin, a hormone that keeps people feeling full after a meal, went down.

Here’s a link to the Harvard Study: Link

Here is why. Nighttime exposure to blue light delays the nocturnal melatonin peak (shifting the circadian rhythm) which decreases the production of cortisol. A balanced consistency of cortisol is much needed to increase the body’s metabolism of glucose.

Studies showed that sleeping with a light or a television on in the bedroom is conclusively associated with gaining five kilograms or more. Also, the study showed the body mass index increase of at least 10% over five years among women. This study published in the medical journal JAMA Internal Medicine and concludes Blue Light puts us at a higher risk of being overweight or obese, compared with being exposed to no artificial light during sleep.

References:

Blue Light, Obesity & Diabetes

A Harvard study identified preliminary results that link blue light to diabetes and possibly obesity.

Blue Light At The Beach

The researchers put ten people on a schedule that gradually shifted the timing of their circadian rhythms similar to what occurs when you look at a screen or mobile phone. The test subject’s blood sugar levels increased, placing them into a pre-diabetic state. Their levels of leptin, a hormone that keeps people feeling full after a meal, went down.

Here’s a link to the Harvard Study: Link

Here is why. Nighttime exposure to blue light delays the nocturnal melatonin peak (shifting the circadian rhythm) which decreases the production of cortisol. A balanced consistency of cortisol is much needed to increase the body’s metabolism of glucose.

Studies showed that sleeping with a light or a television on in the bedroom is conclusively associated with gaining five kilograms or more. Also, the study showed the body mass index increase of at least 10% over five years among women. This study published in the medical journal JAMA Internal Medicine and concludes Blue Light puts us at a higher risk of being overweight or obese, compared with being exposed to no artificial light during sleep.

References:

Blue Light & The Immune System

While we sleep, our immune systems release sleep-promoting proteins/peptides called cytokines. The body requires specific types of cytokines to increase if you’re feeling stressed, have an infection or inflammation.

Blue Light At The Beach

Cytokines act through receptors and play an essential role in the immune system. They are moderating the balance between humoral immunity (release of antibodies that rapidly respond against toxins) and cell-based immunity (release of cytokines that permanently act against disease-causing virus/bacteria. Cytokines also regulate the maturation, growth, and responsiveness of other cell populations that respond to trauma, sepsis, cancer and reproduction.

The production of these infection-fighting antibodies and cells slow down during stages of sleep deprivation.

References:

Blue Light, The Outdoors & Sunlight

As you step outdoors into the sunlight, the human eye is exposed instantly to several visible and invisible light spectrum’s. Blue light and UV light is the most known of these spectrums; they enter our body through the eyes and skin. Initiating chemical reactions in our bodies both inside and outside. A well-known example from UV light is sunburn.Sunlight Outdoors On The Beach. Sunlight & Blue LightSunlight is part of the human race and has been for millions of years, like most animals on planet Earth. It plays an essential role in our survivability as well as being a major contributing factor in the global ecosystem. Sunlight synchronises human and animal sleep cycles known as the circadian rhythm. It’s linked to every part of us, our metabolism, alertness even our mood and mental state. Have you had a stressful day? A short walk in the park or spending time outdoors can completely change how you think and feel, and this is partly due to sunlight.

Blue Light, Sunlight & The Light Spectrum

Many of us do not realise the light emitted by our sun has all the colours of the rainbow. Each colour has a different amount of energy and capability to impact us as humans. Sunlight contains a range of colours, red, orange, yellow, green and blue light, each of these with their specific energy and wavelength (called electromagnetic radiation). When we combine all these colours, we get “sunlight” or “white light”.

Sunlight, The Outdoors, Visible and Invisible Light

Science has proven that the colour we see (or cannot see) links to the wavelength, and this is linked to the amount of energy each colour contains. Long wavelengths, such as those found in the colour Red, has less energy while Blue’s which have shorter wavelengths have more energy. So while we are all cautious about UV light and its damaging effects on our skin and eyes, it sits back to back with Blue Light.

We hope this article clears up where Blue Light sits on the light spectrum. If you want to read more about the damaging effects of blue light, please follow this link: Is Blue Light Dangerous.

Blue Light Blocking Glasses & Sleep

Before the invention of light bulbs, the human circadian rhythm was entirely in sync with the sun because night time light disruption was minimal. At night, exposure to devices emitting blue light is harmful to sleep and the circadian rhythm (the body’s biological clock). Research has proven that Blue Light prevents body temperature from dropping during the night. A slowly decreasing body temperature is a critical process to which the body progresses into the stage of sleep. Blue light keeps the body temperature elevated at day time levels.

Girl unable to sleep at 4am

Studies show that exposure to blue light, even when dim, can suppress the creation of melatonin. This hormone assists in controlling our circadian rhythms. A minuscule eight lux, the level of brightness well exceeded by desk and table lamps, and about twice that of a night light cause disruptions. Light from fluorescent bulbs and LED lights will also produce the same effect.

 

Blue Light, Sleep & Melatonin

The pineal gland in the brain is responsible for releasing melatonin, and it does so for a few hours before you start feeling tired. Melatonin level reaches its peak in the middle of the night.

Falling Asleep On The Lounge

Reading on a blue light-emitting device like a tablet instead of a printed book at night will take you longer to fall asleep due to the lack of melatonin produced. Essentially, blue light is a stimulant which sends a signal to your brain, tricking it into believing its day time, and you should be awake. Research has identified that people exposed to blue light at night tend to have less REM sleep; this is when when dreams occur. Less REM sleep results in tiredness in the morning, even after a full eight hours of shuteye.

 

Stephen Lockley, a Harvard sleep researcher, stated that light at night is part of the reason so many people don’t get enough sleep. The idea that blue light is so problematic is that it has a short wavelength that affects levels of melatonin more than any other wavelength does.

Dr Charles Czeisler of Harvard Medical School identified in 1981 that daylight is the mechanism that keeps a person awake. The outside world runs our sleep schedule, so it makes sense that less blue light at night, can help regulate your biological clock.

Wearing blue light blocking glasses at night will contribute to the elimination of sleep and circadian rhythm issues by preventing blue light from reaching your retinas.

References