[sova]

Although the findings in my previous comment are my own extrapolations from years of dabbling, I'm confident most people can become very healthy by having diet rich in helpful cultures (party in your tummy), all the essential amino acids (that will become good neurochem), and letting the body rest in an aware and balanced state without forcing anything (zen out and in) regularly.

There being no concise source on the matter of general health, diet, good neurochemistry, and mood, I can but offer a collection of disparate books:

Principles of Neuroscience (Kandel, Schwartz, Jessell) is a great textbook.

Emotional Intelligence (Bradberry)

Zen Mind, Beginner's Mind (Suzuki Roshi)

I also read a lot of personal experience vault essays on erowid.org (regarding "experimental medicine," for lack of better terminology)