Light + Health

  A recent dark sky project has had me thinking and researching light pollution, sky glow, and by extension an optical phenomenon that we can experience on most clear days or nights. Rayleigh scattering is an interaction of light with Earth’s atmosphere. It’s most notable characteristic is it scatters lower wavelength light colors (violet and [...]

  InSinkErator, one of the leading manufacturers of garbage disposals, has released its LEDefense line, with antimicrobial light technology added to garbage disposals to fight the odor-causing bacteria that builds up with food waste. Instead of waiting until a disposal smells bad and then using citrus peels or cleaning pods, the product uses always-on light [...]

  Smart homes are evolving from simple convenience systems into environments that react to human biological signals. One company, Ultrahuman, is working to fuse wearables, lab biomarkers, and home automation into a continuous health feedback loop. Ultrahuman, founded in 2019, began with an activity-tracking app and later added metabolic tracking via continuous glucose monitoring in [...]

  Researchers at the University of Edinburgh analyzed whether ultraviolet (UV) exposure in low-sunlight regions is associated with better or worse health outcomes, focusing on deaths from cardiovascular disease, cancer, and skin cancer. Using UK Biobank data from 395,000 white European participants across the UK, they linked individual health and genetic records with estimated UV [...]

  This study used ultra–high-field 7T fMRI to examine how temporal light modulation (TLM) (aka flicker) at different frequencies activates or deactivates brain regions in healthy adults, with a particular focus on whether non-perceptible flicker still drives visual cortex responses. Participants viewed LED stimuli modulated at 50 Hz (clearly perceived as flicker) and at ≥100 [...]

  The field of optogenetics is moving from a research tool toward a potential therapeutic strategy for neurological disease, especially chronic neuropathic pain. Optogenetics works by inserting genes for light-sensitive proteins (opsins) into specific neurons so their activity can be turned up or down with precisely delivered light, more like a targeted dimmer than a [...]

  For the legible version of the above image, click here. It’s worth it. This image was created by Stig Kristiansen, a consultant on light + health in Norway. He painstakingly mapped wavelengths of light to different biological functions. The resulting complexity is the most important takeaway. His LinkedIn post about this mapping can be [...]

By Alexander Willemsen, MSE Based on a paper authored by Eric Bretschneider, Ph.D. The Circadian Stimulus (CS) model is one of the most well-known models for quantifying the circadian impact of lighting. One striking feature that separates the model from other contemporary circadian lighting models is its discontinuous action spectrum. As a consequence, the predicted [...]

  Illuminate the Future of Light and Well-Being at Canada Light Expo 2025 in Toronto, ON, November 12 & 13, 2025. On November 13 at 8:15 AM, at the Canada Light Expo, All Things Lighting® Association will host an interactive workshop titled “Unplugged but Illuminated – Finding Balance in a Technological World.” This engaging session [...]