#154 - Sleep and Cortisol

Delving into the science of cortisol, Matt debunks its social media reputation as a toxic villain. He explains how this essential hormone actually regulates metabolism, immunity, and survival. He also unpacks the healthy "Cortisol Awakening Response" that prepares us for the day and dispels the popular internet myth that a 3:00 a.m. cortisol spike is what wakes you up at night.

Matt contrasts healthy, temporary cortisol spikes - like those from exercise - with the chronic stress that causes actual damage. Highlighting how sleep loss dangerously flattens our daily cortisol curve, he shares five tips for a healthier rhythm: get morning light, prioritize sleep, exercise regularly, skip useless single-sample hormone tests, and ignore normal nighttime awakenings. Ultimately, cortisol is innocent; timing is the true culprit.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

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As always, if you have thoughts or feedback you’d like to share, please reach out to Matt:

Matt: Instagram @drmattwalker, X @sleepdiplomat,

YouTube: https://www.youtube.com/@sleepdiplomat