i ate a lox bagel...then i played some guitar, yeah i washed my hands but now my strings smell like lox. anyway is fish oil bad for the fretboard?
i would imagine that it would just feel gross for a little while

(i hate the feel of oily/greasy things)

but besides that, no harm done
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Yeah in all seriousness... I think fish oil is kinda greasy, so I would recommend giving your fretboard a wipe with a dry cloth or something...
...I can't imagine it doing any serious damage, but it won't be good for it either.

The next time you restring, give it a good clean just to be sure.

Also, if it smells like fish, then it's food. And food goes bad.
You do not want rotting fishy goo on your strings.

Not at all.
mmm lox.

I would just wipe the strings and deep clean soon. =/
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