Hi, I apologize for the inconvenience, I heard Andrew saying something in an episode of the podcast that is contrary to what is found on the internet, the topic is the glymphatic system, Andrew says in the episode that raising the bottom of the bed improves the activity of the glymphatic system, while online I only find the opposite said, to raise the top of the bed, what is the right thing? Thank you a lot 🙏

Based on Andrew Huberman’s description, raise the foot end—not the head end—if you’re trying the bed-positioning method he discussed for glymphatic activity. He described elevating the heels or feet so the head is lower than the legs; in another explanation, he specified raising the foot end of the bed by about 3–5 degrees. 1 2

• Elevating the feet or side-sleeping: Huberman said slightly elevating the feet may improve glymphatic clearance, and also described side-sleeping as a position that may increase clearance. 3
• Fluid dynamics and slow-wave sleep: He explained that the effect of position relates to fluid pressure and flow, and that much glymphatic washout occurs during slow-wave sleep. 4 5

One qualification: Huberman noted that foot elevation can worsen acid reflux; for people with reflux, he said to do the opposite and elevate the head side of the bed. 2