my mom uses a food-grade mineral oil you can buy at cooking supply stores or places that sell butcher blocks. not sure if you can find it at discount stores, though. some cooking sprays (pan coatings) have this oil as an ingredient and supposedly it's not absorbed into your system when using such small amounts?? i'm not sure i'd risk it, though. maybe canola or olive oil would work, too, although if you use the cutting board daily you may not have a problem with it drying out to much.