A 2 day Water Fast every 2 weeks with a plantbased diet in between is not at all unsafe or dangerous: very beneficial in fact.
It only becomes unsafe in the manner I described earlier in the thread where an attempted 60 day fast (too long) without supervision, and the very real risk of an electrolyte deficiency as a result; AND from what has been described on the blog, makes this highly irresponsible.
Some people enter water-fasting as if it were just "going without food", but this simply isn't the case at all. http://www.soilandhealth.org/02/0201hyglibcat/020127shelton.III/020127.ch29.htm
If you don't wish to consume oily fish (wild caught) the best alternative is the oil-protein combination of flaxseed oil with a sulfurated protein (Budwig); this combo makes the oil water-soluble, which in turn allows the EFA's to enter the bodily cells far more easily and therefore therapeutically.