Red Light and Health: The power of natural lighting for well-being

Light is the spectrum of electromagnetic radiation that our eyes detect. At one end is blue light, with a short wavelength. This is the light we see almost everywhere as white. At the opposite end is red light, with a longer wavelength.

Artificial lighting has a large component of blue light , a type of light that disrupts our hormonal processes . Let's see why.

For millions of years, the light humans used in the dark was primarily red, from fire. The only blue light that existed came from the Sun, so this spectrum was used to synchronize our circadian rhythms.

In nature, blue light is very strong during the day, becoming very faint at dawn and dusk. The dominant spectrum then is red and infrared light, which prepares us at dawn to safely receive sunlight during the day and at dusk to increase melatonin production, facilitating, among other things, restful sleep.

Modern life has blurred the difference between day and night . Traditionally, we were exposed to the unparalleled brilliance of the Sun during the day and to darkness (or the red light of fire) at night.

Today, we spend almost the entire day indoors, exposed to the same light intensity both day and night. The result is a profound disruption of our circadian rhythms.

As the following image shows, blue light is clearly the one that most inhibits melatonin production .

As we saw, sunlight acts as the main synchronizer of circadian rhythms, biological cycles that regulate our lives, from sleep patterns to hormone production.

Circadian rhythms and types of light

Exposure to natural light during the day helps maintain these rhythms, while excessive exposure to artificial (blue) light, especially at night, can disrupt them.

This circadian mismatch is linked to various health problems , such as sleep disorders ( study ), depression ( study ) and an increased risk of chronic diseases ( study ).

Beyond sight, we also possess light-responsive receptors throughout our skin. These cutaneous receptors contribute to the regulation of metabolic and repair processes.

Therefore, exposure to light affects our health in a more profound and direct way than simply through circadian regulation.

Another direct consequence of being under blue light is the decrease in melatonin production.

Melatonin not only influences rest, but is also the most important antioxidant we have, a hormone with a fundamental role in our health by improving our redox power to suffer less oxidative damage.

As we can see, light plays a crucial role in our lives beyond simply illuminating our surroundings.

This study conducted on children demonstrates how blue light suppresses melatonin, with implications for sleep , concentration , and performance :
Melatonin suppression and sleepiness in children exposed to blue-enriched white LED lighting at night (Lee et al., 2018).

This is not about creating alarm , but about being aware and choosing that if our little ones we love most are going to watch a movie or look at screens for several hours, and especially when the sun has gone down, a simple pair of quality protective glasses that filter blue light can correct these associated health problems and protect them.

Top image: Kids Protective Glasses - blue light blocking

The role of light in mitochondria

Recent research has revealed how light directly influences biological functions at the cellular level, particularly in mitochondria .

Mitochondria, known as the powerhouses of cells, are responsible for creating most of the energy needed for cellular activity.

Recent studies have shown that certain wavelengths of light (red and near-infrared) can enhance mitochondrial efficiency, thereby improving energy production and reducing the production of reactive oxygen species. This results in a lower incidence of cellular damage and aging.

This study demonstrates that longer wavelengths (660-900 nm) of red and infrared light increase ATP production , while blue light (420 nm) suppresses metabolism.

What does this mean?

Exposure to the red and infrared light of the sun at dawn or dusk, or from a red light bulb, increases mitochondrial activity. And blood glucose levels can be reduced by up to 50% .

On the other hand, exposure to the blue light from the white light bulbs that we have everywhere can raise systemic glucose levels by more than 50%.

This influence of light on metabolism is remarkably consistent across different species, from insects to humans.

This opens a new path towards modulating our metabolism in a way never before imagined.

Artificial light and modern diseases

The scientific literature on the harmful effects of exposure to blue light at sunset is extensive and even overwhelming. It grows daily, demonstrating a direct link to:

overweight ( study ), cancer ( study ), immune system suppression ( study ),
infertility ( study ), diabetes ( study ), bowel disorders ( study ),
mental illness ( study ).

To illustrate, this global study concludes: " Artificial light at night is significantly linked to multiple types of cancer. Immediate action should be taken to limit artificial light at night ."

This other study reveals the protection of the retina by filtering more than 94% of blue light, demonstrating how we can use certified blue light blocking glasses to protect ourselves effectively and easily:
Removal of the blue component of light significantly protects retina (Vicente-Tejedor et al., PLOS ONE, 2018).

In conclusion, light is not only fundamental to our visual perception, but it is a key factor in our biological health and well-being.

By better understanding how we interact with different types of light, we can consciously take steps to improve our health and quality of life by prioritizing light sources that harmonize with our biology.

The importance of flicker

In addition, modern lighting has another problem: flicker . This refers to variations in the brightness and intensity of the light due to voltage fluctuations.

Several studies show that it stresses our eyes and nervous system, potentially causing fatigue and headaches.

These problems have existed since the first incandescent light bulbs (tungsten filament), but the problem has increased exponentially with the use of new technologies: fluorescent and LED.

Fluorescent lights emit a large amount of blue light (with all the problems we've seen from exposure to blue light after sunset) and also have extreme flickering . You can even see the flicker with the naked eye.

Conventional LED technology typically uses very high color temperatures (up to 6000K) that have a large blue component and flicker at a much higher frequency than fluorescent lights. Therefore, we don't consciously perceive it, but our eyes, optic nerve, and nervous system do.

Incandescent bulbs , while preferable to conventional fluorescent and LED bulbs , are not the solution either .

Incandescent light bulbs, powered by 50Hz alternating current, exhibit flicker at 50Hz. While it's true that the filament doesn't allow for 100% flicker due to thermal inertia, it's still a significant variation.

To avoid flickering, all our BIO lighting and bulbs have been manufactured with a direct current power supply and an oversized 100% pure copper coil, which achieves 100% flicker elimination (Flicker Free).

The high-quality, oversized power supply allows the LED to be supplied with direct current without alteration, so it emits a constant light without fluctuations, just like natural light, taking care of our retina, eye and improving all biological and hormonal functions, aligning our daily comfort with our present and long-term health.