At St Ives 2016, we did two talks. One on gemstones and their meanings and one on The Humoural theory.
As part of the humoural theory talk, we recommended
“The fyrst boke of the introduction of knowledge made by Andrew Borde, of physycke doctor. A compendyous regyment; or, A dyetary of helth made in Mountpyllier” written by ah, Andrew Borde, who was Henry the 8th’s physcian after Sir William Butts passed. (They believed in clear titles then….)
For a very basic overview, there’s also the wikipedia page
Here’s a free copy of the Dyetary of helth available online at archive.org
And a version of the hard copy available on book depository, because we like physical copies of books. And also because I personally found the free version extremely hard to read.