This episode I discuss the science and practice of fasting also called time-restricted feeding. I review the data on how limiting food intake to specific portions of every 24-hour cycle (or fasting longer) impacts weight loss, fat loss specifically, liver health, mental focus, muscle, longevity and more. I explain how "fasted" is contextual, and relates to blood glucose levels and their downstream effects, and how the depth of fasting can be adjusted with behaviors such as different types of exercise, or with glucose disposal agents. I also discuss the optimal fasting protocol: and both the absolute (non-negotiable) and variable (contextual) features of a fasting/time-restricted-feeding protocol that will allow you to get the most benefits. I also discuss what does and does not break a fast, the effects of fasting on hormones like testosterone and cortisol and on fertility. I also review how different feeding windows of 8 or 10 or 4 hours differentially impact the effects of fasting, and why the classic 8 hour feeding window came to be but also might be ideal. I discuss mechanisms and offer tools to discern the optimal fasting duration and timing for you. #HubermanLab #Fasting #FatLoss Thank you to our sponsors: ROKA - https://www.roka.com/huberman InsideTracker - https://www.insidetracker.com/huberman Helix Sleep - https://www.helixsleep.com/huberman RETHINK EDUCATION: The Biology of Learning Featuring Dr. Andrew Huberman https://youtu.be/Oo7hQapFe3M Supplements from Thorne: http://www.thorne.com/u/huberman Social: Instagram - https://www.instagram.com/hubermanlab Twitter - https://twitter.com/hubermanlab Facebook - https://www.facebook.com/hubermanlab Website - https://hubermanlab.com Newsletter - https://hubermanlab.com/neural-network Links: Comprehensive Review On Fasting In Humans: https://bit.ly/3BwIyd7 The Huberman Lab Podcast is for general informational purposes only and does not constitute the practice of medicine, nursing or other professional health care services, including the giving of medical advice, and no doctor/patient relationship is formed. The use of information on this podcast or materials linked from this podcast is at the user’s own risk. The content of this podcast is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should not disregard or delay in obtaining medical advice for any medical condition they may have and should seek the assistance of their health care professionals for any such conditions. Title Card Photo Credit: Mike Blabac - https://www.blabacphoto.com