Effects of Fasting & Time Restricted Eating on Fat Loss & Health | Huberman Lab Essentials

Andrew Huberman

Aug 28, 2025

Episode description

In this Huberman Lab Essentials episode, I explore intermittent fasting and time-restricted eating, highlighting the positive benefits for weight loss, metabolism, organ health, circadian rhythms and cellular repair.

I explain a practical framework for designing a time-restricted eating window that aligns with your lifestyle, exercise schedule and social schedule. I also cover what breaks a fast, how to support fasting with tools like salt intake and post-meal walks, and the use of fasting-related supplements, including berberine and metformin.

Episode show notes: https://go.hubermanlab.com/CcvKrMh

Huberman Lab Essentials are short episodes focused on essential science and protocol takeaways from past full-length Huberman Lab episodes. Watch the full-length episode: https://youtu.be/9tRohh0gErM

Watch more Huberman Lab Essentials episodes: https://youtube.com/playlist?list=PLPNW_gerXa4OGNy1yE-W9IX-tPu-tJa7S

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*Timestamps*
00:00:00 Intermittent Fasting, Time-Restricted Eating (TRE)
00:00:50 Diet, Weight Loss, Calories & Hormones
00:05:52 Body’s Response to Eating vs Fasting, Fasting Duration
00:09:04 Time-Restricted Feeding & Metabolic Benefits, Circadian Gene Rhythm
00:14:32 Optimal Meal Timing, Tool: Extend Sleep-Related Fasts
00:19:42 Eating Window Length, Tools: Adjusting TRE for Building Muscle, Regularity
00:22:34 Accelerate Transition to Fasting, Glucose Clearing, Tool: After-Meal Walk
00:24:16 Metformin, Berberine, Continuous Glucose Monitors; Cell Growth vs Repair, mTOR
00:27:25 Gut Microbiome; Transitioning to Intermittent Fasting & Individualization
00:29:43 Tool: 8-Hour Feeding Window & Weight Loss
00:31:05 What Breaks a Fast?, Sugar; Tool: Using Salt to Support Fasting
00:34:08 Tool: Ideal Feeding Window Guidelines; Exercise & Social Considerations

Disclaimer & Disclosures: https://www.hubermanlab.com/disclaimer

Episode description

Mindsip insights from this episode:

Use salt in water to stabilize blood volume during fasting

Consuming a small amount of salt in water can alleviate the lightheadedness and shakiness of fasting by stabilizing blood volume, not by providing energy.

#fasting

#salt

Establish consistent feeding window for optimal health benefits

Having a regular, consistent feeding window each day is more important for health benefits than having a very short window that drifts around from day to day.

#fasting

#routine

Balance fed and fasted states for optimal metabolism

A simple way to think about metabolism is that being in a fed state promotes cellular growth, while being in a fasted state promotes cellular repair and clearance.