Ken Ceder discusses mal-illumination, full spectrum light, UV light needs, problems with SAD lights, fluorescent lighting, photo nutrition & metabolism, and eye health. The conversation explores the impact of different light spectrums on health, benefits of UV light, balance in sun exposure, importance of near infrared light, and harnessing light for health and energy. It also covers optimizing circadian rhythms with morning light, benefits of light therapy, and the power of full spectrum light devices in biohacking.