Mind & Matter
Whether food, drugs or ideas, what you consume influences who you become. Learn directly from the best scientists & thinkers alive today about how your mind-body reacts to what you feed it.
The weekly M&M podcast features conversations with the most interesting scientists, thinkers, and technology entrepreneurs alive today.
Not medical advice.
At M&M, we are interested in trying to figure out how things work, not affirming our existing beliefs. We prefer consulting primary rather than secondary sources and independent rather than institutional voices. If we encounter uncomfortable truths or the evidence suggests unfashionable ideas may be valid, so be it.
As the host, my aim is to help you better understand how the body & mind work by curating & synthesizing information in a way that yields science-based insights that you can choose to use or disregard in your own life. Taking ownership of your health starts with taking ownership of your information diet.
I am motivated to connect the dots and distill general principles from what I learn, preferring to ask questions and play devil’s advocate to debating or incessantly pushing my own viewpoint.
My beliefs:
- Taking ownership of your health starts with taking ownership of your information diet.
- All knowledge is provisional and we must work hard to prevent ourselves from becoming attached to our favorite ideas & preferred conclusions.
- Wisdom comes from an iterative, trial-and-error process of learning and unlearning. Letting go of pre-conceived notions can be painful, but pain is information.
Sometimes modern discoveries teach us we must unlearn received wisdom. Other times, modern information overload & historical chauvinism cause us to forget ancient wisdom which stills applies. The framework for learning that I embody is inspired by three Ancient Greek maxims inscribed in the Temple of Apollo at Delphi:
- “Γνῶθι σεαυτόν” (Know thyself)
- “Μηδὲν ἄγαν” (Nothing in excess)
- “Ἐγγύα πάρα δ Ἄτα” (Certainty brings insanity)
Mind & Matter
Sleep, Brain Fat & Oxidative Stress | Amita Sehgal | 286
Use Left/Right to seek, Home/End to jump to start or end. Hold shift to jump forward or backward.
Is the fundamental purpose of sleep to remove oxidized fats from the brain?
Nick & Dr. Amita Sehgal talk about the latest science on why animals sleep. Using fruit flies, her lab shows that waking generates oxidized lipids in neurons that are shuttled to glia and then cleared by macrophage-like cells during sleep. This process protects mitochondria, supports memory, and links sleep to metabolic cleanup rather than just rest.
TOPICS DISCUSSED:
- Drosophila as a model: Fruit flies sleep with immobility, reduced responsiveness, and homeostatic rebound; their genetics reveal conserved mechanisms found in humans.
- Circadian vs homeostatic sleep: Circadian timing sets when we sleep; homeostatic drive builds need from prolonged wakefulness independent of time of day.
- Metabolic waste during wake: Neuronal activity oxidizes lipids in mitochondria; these damaged lipids transfer to glial support cells via apolipoproteins.
- Immune cells clear brain trash: Macrophage-like hemocytes dock at the brain during sleep, phagocytose oxidized lipids, and remove them; blocking this docking reduces sleep and impairs memory.
- Peroxisomes & oxidative stress: These organelles handle specific fats and rise with wakefulness; disrupting them increases brain oxidation that can be partially rescued by antioxidants like N-acetylcysteine.
- Sickness sleep differs from normal sleep: Infection-induced sleep redirects energy to immune defense and depletes rather than restores brain energy stores.
ABOUT THE GUEST: Amita Sehgal, PhD is the John Herr Musser Professor of Neuroscience at the University of Pennsylvania, an HHMI Investigator, and director of the Chronobiology and Sleep Institute. She uses Drosophila genetics to uncover basic mechanisms of circadian rhythms and sleep.
RELATED EPISODE:
- M&M 257: Sleep, Mitochondrial Metabolism & Oxidative Stress | Gero Miesenbock
Health Products by M&M Partners:
- SporesMD: Premium mushrooms products (gourmet mushrooms, nootropics, research). Use code 'nickjikomes' for 20% off.
- Lumen device: Optimize your metabolism for weight loss or athletic performance. MINDMATTER gets you 15% off.
- AquaTru: Water filtration devices that remove microplastics, metals, bacteria, and more from your drinking water. Through link, $100 off AquaTru Carafe, Classic & Under Sink Units; $300 off Freestanding models.
- Seed Oil Scout: Find restaurants with seed oil-free options, scan food products to see what they’re hiding, with this easy-to-use mobile app.
- KetoCitra—Ketone body BHB + electrolytes formulated for kidney health. Use code MIND20 for 20% off any subscription (cancel anytime)
For all the ways you can support my efforts
