we don't. until more studies are found there is some guessing here. just that one study said it acts kind of like estrogen. That should make it shrink body hair. But it grew a lot. So maybe it is a growth stimulant, with stimulating abilities that far outweigh the estrogen effects. I'd like to test it on my toe too. I'm glad MB found the good stuff for us, but we should confirm it on our toes before putting it on our heads.
