How you can use blue light to regulate circadian rhythm.
Controlling your blue light exposure can be a powerful tool to improve your sleep, balance hormones and improve your energy and alertness. This means getting sufficient blue light exposure at times and limiting or eliminating blue light at others based on your natural circadian rhythm.
How to do it
I typically try to get most of my blue light exposure in the morning, including as much natural sunlight as possible. I try to limit my blue light exposure during the day to protect my eyes and slow cellular damage. During the day I try to stay out of fluorescent lights, adjust my screens to lower the blue light settings, and wear partial blue light blocking glasses (like pictured) while in the office. At night (2 hrs before bed) I try to eliminate blue light to support my sleep by using halogen and incandescent light bulbs, not using screens, or, if I have to, using my “stronger” orange lens blue light blocking glasses, and using blackout curtains in my bedroom.
How it works
Blue light is everywhere and it influences our hormone secretion, heart rate, alertness, sleep, body temperature, and gene expression. Sources of blue light include the sun, digital screens, TVs, computers, fluorescent lights and LEDs.
In the morning, blue light can wake you up and help you feel alert and energized through your day, but too much of it at night can impact your sleep. Too much blue light at night messes with your circadian rhythm by suppressing melatonin hormone which usually signals to your brain that it’s time to sleep. It tricks your body into thinking it’s daytime and keeps you in an awake state.
Blue light can also cause cellular damage and speed the aging process by inducing oxidative stress lipid peroxidation and retinal degeneration. Overexposure to blue light also increases your risk of chronic illnesses like heart disease, cancer, obesity, and diabetes.