Summary
Overview
Dr. Glenn Jeffrey, a neuroscience professor from University College London, discusses how different wavelengths of light impact mitochondrial health, cellular function, and overall longevity. He explains that long-wavelength light (red and infrared) can improve mitochondrial function and cellular health, while excessive short-wavelength light from LEDs may damage mitochondria. The conversation covers practical applications including vision improvement, blood sugar regulation, and the serious public health implications of modern indoor lighting environments.
Understanding Light Wavelengths and Their Impact on Biology
Dr. Jeffrey introduces the concept that light extends far beyond what we can see, from ultraviolet (around 300nm) through the visible spectrum (400-700nm) to deep infrared (nearly 3,000nm). He explains that short-wavelength UV light carries a "kick" that causes sunburn and is blocked by our skin and eyes, while long-wavelength light penetrates deeply into tissues. The distinction between ionizing and non-ionizing radiation is critical—short wavelengths can alter DNA, while long wavelengths support healthy mitochondrial function.
- Sunlight extends from about 300nm (UV) to 3,000nm (infrared), far beyond the visible range of 400-700nm
- Short-wavelength UV light is blocked by skin and causes sunburn as an inflammatory response
- Our lens and cornea block short wavelengths, which is why we don't see them and why cataracts develop with age
- Long-wavelength light penetrates deeply through tissues and passes through bone, unlike short wavelengths
" This is an issue on the same level as asbestos. This is a public health issue and it's big. "
" Sunlight extends out almost to 3,000 nanometers. Just think about it. Big, big range. "
How Long-Wavelength Light Powers Mitochondria Through Water
Dr. Jeffrey explains the groundbreaking discovery that mitochondria don't directly absorb long-wavelength light—rather, the water surrounding them does. This absorption changes the viscosity of nano-water in mitochondria, allowing the ATP-producing motors to spin faster. Beyond immediate effects, long-wavelength light also triggers the synthesis of more mitochondrial proteins, creating more energy-producing chains. This represents a fundamental shift in understanding how light therapy works at the cellular level.
- Water in mitochondria absorbs long-wavelength light, changing its viscosity and allowing ATP motors to spin faster
- Long-wavelength light exposure causes synthesis of more mitochondrial proteins, creating more energy-producing chains
- The mitochondrial motor starts spinning faster immediately, then the body lays down more tracks for long-term benefit
- Mitochondria originated as independent bacteria that evolved in water, explaining their response to long-wavelength light
" When we give long wavelength light, we find the proteins in those chains, we find a lot more of them. So my analogy is that giving red light gets the train to run down the track faster. That's true. But then something detects the speed of that train and says, lay down more tracks. "
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