As well as this singing work, Dao has also been running Detox Retreats for 20 years, which take groups of health seekers through fasts. During the retreat, Dao gives daily talks on the physiology of the body and the effects of diet upon both physical and emotional health.
What on Earth is Food, is a written form of these talks - 300 odd pages to help you understand why foods do or don’t work for your mind/body equilibrium.
This is the physical book. You can also find it on Amazon as an Ebook