"Specifically, cancer, depression, anxiety, joint pain? "
There isn’t a specific dosing guideline for different ailments. Dosing varies greatly from one individual to the next even with the same conditions. Here is a guide that suggests starting dosages and gives tips how to find your optimal dosage.
https://www.projectcbd.org/sites/projectcbd/files/downloads/pcbd_dosingguide_2-12-2015_2.pdf
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