bestreviews.com › food-drink › oils5 Best Food-Grade Mineral Oils - Nov. 2022 - BestReviews Body: Mineral oil has long been used as a natural laxative to help soften stool. Counters and sinks. Use food-grade mineral oil to develop a rich patina and enhance the beauty of soapstone sinks and countertops. The oil will also help granite countertops darken evenly, while other types of oil like citrus or linseed can cause granite to discolor.