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Huberman Lab

Using Red Light to Improve Metabolism & the Harmful Effects of LEDs | Dr. Glen Jeffery

134 min episode · 2 min read
·
Glen Jeffery

Episode

134 min

Read time

2 min

Topics

Health & Wellness, Science & Discovery, Economics & Policy

AI-Generated Summary

Key Takeaways

  • Long wavelength light penetration: Red and near-infrared light passes completely through the human body, including bone and skull, scattering internally to reach mitochondria in all organs. A small four-by-six inch patch of light on the back creates systemic effects throughout the body within one to two hours.
  • Vision improvement protocol: Exposing eyes to 670+ nanometer light for three minutes in the morning (before 11 AM) improves color vision by 20% in people over 40. Effects last exactly five days across all species tested. Low energy levels (one milliwatt per centimeter squared) prove effective, making dim red light sufficient.
  • Blood glucose regulation: Shining long wavelength light on a small area of the back before consuming glucose reduces blood sugar spikes by over 20%. The effect occurs because stimulated mitochondria consume more glucose systemically, not just locally. Morning exposure produces strongest results due to circadian mitochondrial activity patterns.
  • LED lighting damage: Standard LED bulbs contain high levels of short wavelength light (420-440 nanometers) without balancing long wavelengths. Mice under LED lighting develop fatty livers, smaller organs, abnormal sperm morphology, and impaired glucose metabolism. Researchers compare this public health risk to asbestos exposure based on population-level lifespan data showing flattening after 2010.
  • Incandescent light restoration: Replacing LED lighting with 40-watt incandescent desk lamps for two weeks improved color perception significantly, with effects lasting over one month after removal. Incandescent and halogen bulbs provide smooth spectrum light similar to sunlight and firelight, which humans evolved under for millions of years.

What It Covers

Dr. Glen Jeffery explains how red and near-infrared light (650-900 nanometers) improves mitochondrial function by affecting water viscosity, enhances vision by 20% in people over 40, reduces blood glucose spikes by 20%, and how LED lighting may damage cellular health.

Key Questions Answered

  • Long wavelength light penetration: Red and near-infrared light passes completely through the human body, including bone and skull, scattering internally to reach mitochondria in all organs. A small four-by-six inch patch of light on the back creates systemic effects throughout the body within one to two hours.
  • Vision improvement protocol: Exposing eyes to 670+ nanometer light for three minutes in the morning (before 11 AM) improves color vision by 20% in people over 40. Effects last exactly five days across all species tested. Low energy levels (one milliwatt per centimeter squared) prove effective, making dim red light sufficient.
  • Blood glucose regulation: Shining long wavelength light on a small area of the back before consuming glucose reduces blood sugar spikes by over 20%. The effect occurs because stimulated mitochondria consume more glucose systemically, not just locally. Morning exposure produces strongest results due to circadian mitochondrial activity patterns.
  • LED lighting damage: Standard LED bulbs contain high levels of short wavelength light (420-440 nanometers) without balancing long wavelengths. Mice under LED lighting develop fatty livers, smaller organs, abnormal sperm morphology, and impaired glucose metabolism. Researchers compare this public health risk to asbestos exposure based on population-level lifespan data showing flattening after 2010.
  • Incandescent light restoration: Replacing LED lighting with 40-watt incandescent desk lamps for two weeks improved color perception significantly, with effects lasting over one month after removal. Incandescent and halogen bulbs provide smooth spectrum light similar to sunlight and firelight, which humans evolved under for millions of years.

Notable Moment

Jeffery reveals that passing long wavelength light through one side of a newborn's head and measuring it on the other side provides a metric of mitochondrial function that predicts survival after stroke. This non-invasive diagnostic technique has been approved by multiple ethics committees and implemented in major London hospitals.

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Episode Transcript

Let's talk about indoor lighting Mhmm. Because I am very concerned about the amount of short wavelength light that people are exposed to nowadays, especially kids. This is an issue on the same level as as asbestos. This is a public health issue, and it's big. And I think it's one of the reasons why I'm really happy to come here and talk because it's time to talk. When we use LEDs, the light found in LEDs, when we use them, certainly, we'll be using them on on the retina looking at mice. We can watch the mitochondria gently go downhill. They're far less responsive. They their membrane potentials are coming down. The mitochondria are not breathing very well. Watch that in real time. Welcome to the Huberman Lab Podcast where we discuss science and science based tools for everyday life. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. My guest today is doctor Glenn Jeffrey, a professor of neuroscience at University College London. In today's episode, we discuss how you can use light, in particular red near infrared and infrared light to improve your health. And no, not just by getting sunlight. Although we do talk about sunlight, doctor Jeffrey's lab has discovered that certain wavelengths or colors of light can be used to improve your skin, your eyesight, even your blood sugar regulation and metabolism. Doctor Jeffrey explains how light is absorbed by the water in your mitochondria, the energy producing organelles within your cells, to allow them to function better by producing more ATP. He also explains how long wavelength light, things like red light, can be protective against mitochondrial damage caused by excessive exposure to things like LED bulbs and screens, which of course we are all exposed to pretty much all day long nowadays, and simple, inexpensive, and even zero cost ways that you can get long wavelength light exposure, and again, not just by getting more sunlight. He explains that long wavelength light can actually pass into and through your entire body, and that it scatters when inside you. Now that might sound scary, but it's actually a great thing for your health because that's how long wavelength light can improve the health of all your organs by entering your body and supporting your mitochondria. Believe it or not, certain wavelengths of light can actually pass through your skull into your brain and help promote brain health. During today's episode, we also discuss new findings that correlate the amount of sunlight you're exposed to with longevity. Those are very surprising findings, but they're important. Also, why everyone needs some UV light exposure. And we discuss whether it's important to close your eyes when using red light devices or in red light saunas. And how best to apply red light and things like infrared light in order to drive maximum health benefits. Today, you're going to learn from one of the greats in neuroscience as to how …

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