<<<.........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