Summary
Dr. Roger Seheult, a board-certified physician in internal medicine, pulmonary diseases, critical care, and sleep medicine, discusses the powerful benefits of light therapy for immune function and overall health. The conversation covers infrared, red, and sunlight exposure for improving mitochondrial function across all organs, and explores evidence-based strategies for reducing the risk of influenza, colds, and other respiratory and gut infections.
They review a wide range of practical topics including the efficacy of the flu shot, whether handwashing truly prevents illness, treatments for long COVID and mold toxicity, the therapeutic potential of N-acetylcysteine (NAC), and hydrotherapy for combating infections. The episode also addresses air quality, melatonin's relationship with light exposure, the importance of avoiding bright light at night, and strategies for improving sleep and immune resilience.
Key Points
- Sunlight and infrared light exposure improve mitochondrial function and support immune health across all organs
- Near-infrared light (670nm) can improve blood glucose levels and color contrast sensitivity
- NAC (N-acetylcysteine) attenuates flu-like symptoms and boosts cell-mediated immunity
- Hydrotherapy and contrast water therapy have historical and emerging evidence for fighting infections
- Avoiding bright light at night and getting daytime sunlight are critical for melatonin production and immune function
- Forest bathing and phytoncides from trees enhance natural killer cell function
- Temperature elevation (fever) activates antiviral interferon pathways in the body
Key Moments
Sun and red light therapy have a medical history — it's not just biohacking
Dr. Seheult explains how sun and red light stimulate mitochondrial health across the brain and body. Phototherapy has well-established mechanisms of action beyond what most people realize.
"Sun and red light therapy have a long and well-established medical history and their mechanisms of action are known — it's not just biohacking."
After age 40, mitochondrial ATP output drops 70% — infrared light can help reverse it
Infrared light penetrates through clothes and skin to reach mitochondria, which produce on-site melatonin in concentrations far higher than the pineal gland. This mitochondrial melatonin acts as an antioxidant, not a sleep signal.
"After 40 years, the output of mitochondria, which is ATP, drops by about 70%. Can you imagine being in your house and the energy production drops by 70%?"
Why we never get blue light without red light in nature — and why LEDs are a problem
In nature, UV and blue light always come packaged with infrared light. Scientific reductionism led us to fear all sun exposure. Hospitals used to put patients on sun decks 100+ years ago for recovery.
"This is really the first time in human history that we've had this preponderance of short wavelength blue and green light in the absence of red light."
Just 100.4°F core temp dramatically boosts interferon signaling — you don't need a full fever
Research shows that raising core body temperature to just 38°C (100.4°F) dramatically increases interferon signaling through the STAT/JAK pathway. The temperature increase directly upregulates nuclear transcription. Sauna with a hat lets you stay longer by insulating the brain.
"At 38 degrees, which is only 100.4 Fahrenheit, there was a dramatic increase in the signaling in probably six or seven different areas of the STAT and the JAK system."
LED lights emit zero infrared — a candle is under 10 lux but a hotel thermostat is 100-400
LED lights are "efficient" because they cut out infrared and red wavelengths. A campfire or candle produces under 10 lux, while a dim LED nightlight puts out 100-400 lux — enough to disrupt glucose regulation.
"That wall nightlight or thermostat light messes up our glucose regulation as shown in really good peer-reviewed studies."
