![127 - AMA #3 with sleep expert, Matthew Walker, Ph.D.: Fasting, gut health, blue light, caffeine, REM sleep, and more - Peter Attia 127 - AMA #3 with sleep expert, Matthew Walker, Ph.D.: Fasting, gut health, blue light, caffeine, REM sleep, and more - Peter Attia](https://peterattiamd.com/wp-content/uploads/2020/09/hero-image-matthewwalkerama3-1440x500.jpg)
127 - AMA #3 with sleep expert, Matthew Walker, Ph.D.: Fasting, gut health, blue light, caffeine, REM sleep, and more - Peter Attia
![Matt Walker on Twitter: "Associational study showing that nearly 25% of a student's grade is predicted by sleep in the weeks before the exam. Suggests sleep hysteresis: it's not simply sleep the Matt Walker on Twitter: "Associational study showing that nearly 25% of a student's grade is predicted by sleep in the weeks before the exam. Suggests sleep hysteresis: it's not simply sleep the](https://pbs.twimg.com/media/EPT3xxzVUAEM7yT.jpg)
Matt Walker on Twitter: "Associational study showing that nearly 25% of a student's grade is predicted by sleep in the weeks before the exam. Suggests sleep hysteresis: it's not simply sleep the
![127 - AMA #3 with sleep expert, Matthew Walker, Ph.D.: Fasting, gut health, blue light, caffeine, REM sleep, and more - Peter Attia 127 - AMA #3 with sleep expert, Matthew Walker, Ph.D.: Fasting, gut health, blue light, caffeine, REM sleep, and more - Peter Attia](https://peterattiamd.com/wp-content/uploads/2020/09/127-Matthew-Walker-AMA@1.5x-80-v3.jpg)