You need to treat it with mineral oil (aka paraffin oil) a few times a year. This prevents the wood from drying out. I've also tried mixing in bees wax with the mineral oil as this adds a degree of protection from spills. Other than that just make sure you wipe up any spills before they soak in.
Liberon finishing oil is what you need for worktops. Food safe, heat and water resistant, and lasts for a year or so before needing to reapply. Not that cheap but well worth it.