<<<.........recommends mom use olive oil on their nipples. It has been around for thousands of years and is safe. Later I also read that olive oil contains vitamin E which helps condition skin.>>> My pharmacopoeia does not mention Vitamin E in olive oil, just glycerides, mainly with oleic acid, with smaller amounts of palmitic, linoleic, stearic and myristic acids. There are various refinements, rarely pharmaceutical grade. Information on pesticide residues is not available, but one would have to assume they are present - unless they have been specifically removed. When deciding between topicals for nipple use, it is worth having a basic understanding about how they work in relation to skin. LCs seem to be either in the topical or no-topical camp, but their position is usually based on prejudice or preference, rather than knowledge. Olive oil is a common emollient used to soften ear wax, crusts, or the dry outer layer of skin. It forms an occulsive (not oxygen permeable) barrier on the skin, and I would expect it to be comedogenic (clog pores). Olive oil, like most oils, is water repellent and remains on or close to the surface of the skin. It therefore tends to be rubbed off by clothing, with residues remaining slippery on the surface. It moisturises mainly by softening the dry outermost layer of skin cells and by preventing water evaporation. Skin maceration can occur. In contrast, anhydrous lanolin can spontaneously absorb 2 to 3 times its own weight in water. Lanolin moisturises by penetrating the full depth of the stratum corneum where it occupies intercellular spaces and emulsifies local water to form reservoirs of internal moisture, available to the surrounding cells as required. Some remains on or near the surface of the skin, forming a semiocclusive moisture barrier that permits gaseous exchange and evaporation of excess moisture, so maceration does not occur. Simply put, this means that oils and lanolin have quite different moisturing methods. In situ studies suggest that the deep moisturising effect of lanolin appears to be the more effective. Ingestion is more of an issue for a baby (while the gut is more permeable) than a toddler, but should be considered with any topical used on nipples. Vitamin E Oil should be avoided for reasons of allergy and toxicity. Ros Escott BAppSc IBCLC Tasmania, Australia