>>The better way to sleep, get well-rested, and wake up feeling youthful is to sleep on your back.

Just be aware that there have been rodent (not human but our glial systems are similar to theirs) studies indicating that the system that removes the days waste products and oxidized byproducts during NREM3/4 sleep is more effective in a lateral (side) sleeping position.

So you get a choice between aging your face and aging your brain.