Studies as in vitro or vivo? Vitro I agree, a lot of the studies can be disregarded but vivo studies should be looked at more closely.
2 out of 3 5AR inhibitors you just named also have anti estrogenic properties (zinc and resveratrol) which is probably off sets any 5AR inhibition. I take both of those supplements everyday (sustain alpha and zinc picolinate) with no problems. I couldn't tell you my personal experience with rice as I eat keto but I doubt a food would have a similar effect in terms of potency compared to an herbal extract.
Regarding Tococaps, read this thread (post #126 and #127):
Eric Potratz.... new company, new product! - Page 13
5ARI properties with phytosterols occur with 300mg per day, tococaps contains under 10mg per serving so that is why it doesn't effect us much (I use tocotrienols too with no sides)
"The main ones I would avoid are: Finasteride/dutasteride (obviously), saw palmetto berry or extract/beta-sitosterol, pygeum, or high dose zinc. Those are all proven to cause people PFS-like problems."
I would also include fenugreek (read this:
Saw Palmetto and Fenugreek...im in trouble!), stinging nettle root (I had issues with it; so did others and I think CD nuts too did read this thread:
Super Man Herbs - Page 8)
Point is to just be careful regarding what you take. By taking in a bunch of natural 5ARI's could be just as detrimental especially to anyone who suffered/suffers from PFS as we are already sensitive enough. I think as time goes on though and you keep recovering your body can handle them normally again. I remember a year ago I couldn't handle one drop of caffeine and now I'm back to drinking a light cup of coffee again and some tea and feel fine.