I like the idea of feeding the body (via skin) with olive oil, and coconut oil too, (edit.I mean, normally speaking, to soften and nourish the skin, that is. Not something I'd be thinking of as a necessary adjunct to a WFAST)
So, I don't think I'd do it on the longer WF, where I want the full-on water experience. I did however, use some pink Himalayan salt in the bath, at one point, on the 29 day WF. Technically, that might be a form of "feeding" the body with minerals. It was a one-time thing, and felt great.
I also floated rose geranium leaves in the bath--wow! and actually, I started to feel as if I was eating by scent.
I mean, really feeling like smelling a flower's nectar was feeding me.
Summer is so much easier than winter!
Spring is good too.
Might do a little oil massage *in the first three days*, WY, just to get over the hump, IF it relaxed me, and helped with any first-three-days trepidation/jitters. Those first three days were a bit anxious for me, in moments. I didn't want to quit, but there is a little (mental-emotional) fence you have to sort of stop seeing as a scary fence, and just hop over it, in my experience. Turns out it's not so high after all. :-) I had a lot of help from EFT. As I am ALWAYS saying.
Yhe longer the fast went, the less I was troubled by anything, that is, until the sheer boredom of my 'spitting crisis' the last few days of the first WFast :-) let's not revisit that. It wasn't really bad, just terribly wearisome.
C