103. Photoimmunology, Circadian Biology & The Hidden Effects of Light | Dr Alexander Wunsch

Sunlight is not simply an immune stimulant or suppressant—it's a dynamic modulator of the immune system, with daytime exposure priming cellular defenses and nighttime allowing for humoral immune repair. Dr. Alexander Wunsch reveals that the body's response to light is deeply tied to circadian biology: the immune system operates in opposite modes across day and night, and artificial light at night disrupts this rhythm by overstimulating the pituitary gland via melanopsin-rich retinal cells. This chronic overstimulation, driven by blue-enriched LED lighting, contributes to metabolic dysfunction, insulin resistance, and inflammation—what Wunsch calls '21st-century scurvy' due to near-infrared deprivation. He argues that modern indoor lighting, stripped of natural spectral balance and rich in flicker, creates a biologically mismatched environment. The solution? Replicate ancestral light conditions: use low-voltage, flicker-free, near-infrared-enriched lighting (like his Heliolumen LEDs), avoid artificial light at night, and prioritize sunrise/sunset exposure. The gold standard? A 12V DC-powered halogen lamp with a PELV transformer to eliminate electrical fields and flicker—essentially recreating the safe, natural light of a fire or forest canopy. The episode dismantles myths about photobiomodulation, warning that many consumer devices deliver dangerous irradiance levels, often due to poor engineering and unregulated LED binning.