The sun provides a wide spectrum of light including UVB from which our body produces vitamin D from cholesterol by the resonating of hydrogen bonds. The sun also provides natural infrared light to decrease interfacial water viscosity in mitochondria that is actually around 40% of the entire spectrum.
Chronobiology has shown us that the different compositions of light throughout the day are essential for us.
The energy that the sun communicates to mitochondria in the form of photons that carry visible light is the key as it makes the metabolic water less viscous and therefore more efficient at proton moving via tunneling, delocalization and destabilization; atomic processes that are severely compromised by deuterium.
Avoidance of excess blue light from screens and indoor lighting especially at night is also key.