UVB exposure to the eyes triggers the release of endogenous opioids, which act as natural painkillers and increase your tolerance for pain.

Wearing blue blockers during the day is likely a disservice as you are blocking the short-wavelength light needed for powerful biological effects on hormones and pain reduction.

In individuals 40 years or older, viewing 670nm red light for a few minutes daily can improve visual acuity by rejuvenating aging photoreceptor cells in the eye.

It is the exposure of your skin to UVB light, not your eyes, that triggers increases in the hormones testosterone and estrogen.

Most melatonin supplements contain doses that are far too high to be physiological and can have unintended effects beyond just sleep, such as suppressing gonad function.

UVB light exposure to the melanopsin cells in your eyes is critical for triggering the turnover of stem cells in your skin, hair, and nails.

Trying to get beneficial sunlight exposure through a car windshield or a window won't work because most windows are designed to filter out UVB light.

If you need to be awake late at night, red light is the best choice as it is less likely to inhibit melatonin or disrupt your cortisol rhythm compared to other light colors.

To protect your mood and dopamine levels, you should avoid exposure to bright artificial light between the hours of 10 pm and 4 am.

To minimize sleep disruption, place any artificial lights you use in the evening low in your physical environment, as the light-sensitive cells in your eyes primarily detect light from above.