> How often is the Epsom Salts ,olive oil/grapefruit juice flush safe to do?
It is safe to do it every 2 weeks for most people - even for seriously sick people.
Seriously sick people should (read must) do parasites cleanse.
If you are healthy, you can do one cleanse every 7 - 10 days.
It is also safe to do 3 flushes in a raw, day after day, in case you have an acute problem - stone stuck in the common bile duct or a serious health problem related to liver full of huge stones.
Every person is different and you must find what is safe for you, by try (and error) ...