Although I am unaware of any studies on the use of coconut oil for sore nipples, and I didn't look in my texts because I assumed you already had,  I was able to find references for the use of lauric acid as an antibacterial agent  Lauric acid is found in very few compounds, the most important of which is human milk :)  I think it's one of those things where we are learning as we go, and it makes sense because we also tell moms to express their own milk onto their sore nipples.  The coconut oil would just be adding additional lauric acid which should logically increase the antimicrobial activity, unless for some reason I'm not imagining it would be too much of a good thing.

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