Abstract: Natural intestine-functional and preservative additive with antioxidative characteristics used as addition in feed for animals and a natural additive with antioxidative characteristics for use as addition in oxygen sensitive products including food products, feed products, cosmetics, pharmaceutics and other oxidation sensitive products for human or animal use. The additive is cost-efficient and can be derived from a plant material originating from olive (Olea europaea L.). The additive is effective as addition to feed, when breeding and producing livestock, as a substitute for traditional growth promoters, which are now being phased out, and as a substitute for synthetic antioxidants, which have shown carcinogenic characteristics.