I'm not sure whether or not heavy mineral oil which I found in the constipation section of my local pharmacy is food safe or not. I presume it is ingested as it's a laxative but am not certain if it's adequate for the cutting board. If not can someone please tell me where to find the food safe stuff? Thanks in advance!
If it is plain mineral oil with nothing added to it, I would imagine it is safe to use on your cutting board. I don't think I have ever seen mineral oil specifically for constipation.
You want to make sure there isn't anything besides mineral oil in it, or it will go rancid on the wood of your board. Also, vegetable oil, canola oil, and olive oil will all go rancid on your board.