Ever wonder why you feel more awake and alert after that 10-minute walk outside? Turns out it’s not all in your head – there’s actually a biological reason why getting outside and being exposed to natural light can help you feel more alert and productive. For centuries, light has dictated our daily lives; humans are programmed to respond to light, although different light wavelengths, or colors, can have different effects on our bodies and our energy.
Green light, in the middle of the spectrum, is one of the most balanced of all the colors. We tend to think of green as calming – like taking a walk in a nice, relaxing forest, and it has stimulating properties like blue light does.
It’s so stimulating that studies have shown it’s the most effective color for promoting wakefulness throughout the night for shift and overnight workers. If you’re working a job that tends to fight with your natural circadian rhythms, getting some green light exposure can help your body adjust. It’s one of the most effective colors in the light spectrum for inducing alertness and promoting wakefulness.
One of the downsides of promoting wakefulness at night is that it can damage a natural circadian rhythm. Like green light, blue and white light also promote the same type of wakefulness, but have a stronger impact on the circadian rhythm and do longer-term damage than comparatively balanced green light does. Blue light, for example, has been shown to shift circadian rhythms twice as much as green light does, so try to stay away from blue light at night. Main sources: your computer, your trusty phone, and the TV, but there are free programs like f.lux available that limit blue light production – and help protect you from those late-night Netflix binges!
If you do need some overnight stimulation – for finishing that Walking Dead marathon or something else – basking in green light can be both an effective and relatively gentle option.
In addition to its effects on energy, green light has been used to improve skin quality and promote anti-aging by affecting melanin-producing cells and inhibiting their production of melanin. Inhibiting the production of melanin can help correct hyperpigmentation, reduce freckling, and eliminate sun spots.
Red light, at the far end of the spectrum, is the most commonly used color of light today for light therapy.
It is increasingly evident that red light is a powerful facilitator of sleep, in direct contrast to green light. Evidence shows that this form of light, in wavelengths from 600-900 nanometers, induce melatonin production in the body. Melatonin is important at bedtime because it is a hormone that induces sleep. It’s the original sleep aid, and basking in red light can increase your production of it.
Using red light to fall asleep at night has an added benefit: infrared light, at the far end of the red light spectrum, has been shown to induce healing and promote mitochondrial (energy-producing cells) regeneration, resulting in improved energy with long-term use. If you’re feeling a bit low in the energy department, consistently getting under a red light can help recharge the batteries. If you’re going to give it a whirl at home, bulbs like this on Amazon fall in the right light spectrum of 700-900nm.
Other than its effects on sleep and energy, red light can also improve skin quality. Unlike green light’s ability to improve skin discoloration and freckling, red light has been shown to heal other skin problems such as wrinkles, rosacea, scarring and eczema. The light triggers production of cytokines in cells, which cause fibroblasts, or collagen producing areas, to become more active. Increased activity of these areas helps improve skin quality.
It’s easy to incorporate light therapy into your daily life; multicolored lights can be purchased everywhere from Ikea to Amazon, but make sure to buy one that provides both red and green light. Just set up the lights up in your preferred location: turn on the green light upon waking and flip the red light on while preparing for bedtime. 15-20 minutes of exposure of each kind of light will help support your natural circadian rhythms and make your mornings and evening more productive!
If that’s not an option, at least do yourself a favor and hop outside for a few minutes every day. Sunlight has all these spectrums and more… Getting some sunlight is good for your vitamin D levels, your circadian rhythms, and your soul.
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