Well... This "oil my fret/finger board" thing comes up all the time. So, here - once again - are my thoughts...
1. Are you
sure your fingerboard is unfinished? A number of luthiers here have said that very few of them actually are unfinished; that even though they look that way, they've been " sealed at the factory"... So, maybe yes, maybe no, But, if it
is actually sealed, you're wasting your time - and money...
2. The people who say you don't need to put anything on the fret/fingerboard, IMO, are right... sorta. If you live in a place where there's actual humidity - or you keep your instruments in a climate-controlled music room? No, you probably don't need to do anything to it but wipe them off once in a while, and keep them clean. However.. if you live someplace where humidity is in very short supply - like, say Las Vegas, where the yearly average relative humidity is a whopping 26% (yes, it really
is a dry heat

)? Yeah, unless you want it to look like a 150-yo abandoned miner's shack, you better put something on there once in a while. However, IIRC, St. Louis is pretty humid most of the time, so... just keep it clean, maybe?
3. If you want to put something on it anyway? Personally, since I don't want my fretboards looking/feeling like an abandoned miner's shack, I use linseed oil on any fretboard that isn't sealed; lacquered; synthetic; or ebony. For ebony, I follow Alembic's instructions; real, genuine 100% lemon oil - the kind you get from a health food store. No, unlike most furniture polish "lemon oil", it
is not "just lemon-scented mineral oil". It's real, actual lemon oil (pressed from the peel); and yes, it's expensive. I figure that, for a bass that cost $8,000 (last time I looked), I'll for damn sure do what the folks who made the thing say to do... I have several other instruments with ebony fretboards; the stuff really does works great on ebony. But, yeah, bore oil, Dunlop 65 lemon oil, or mineral oil will work, too... For the ones that are sealed, lacquered, or synthetic? I just wipe them off with a damp cloth, and keep them clean...
4. Yes, food oils are a bad idea. They
will go rancid, and/or get moldy. When they do... good luck getting them off (or, more importantly,
out) of your fingerboard. They're a definite no-no...
However... in the end, it's your instrument. Do what you think is best...