I’ve heard that lavender oil can cause breast swelling in young boys? Should I not use this on my son?

Researchers have been very hotly contesting the data regarding lavender oil and gynecomastia (breast swelling) in young boys. This is evidenced by the significant number of response comments in New England Journal of Medicine. A response article entitled “Lack of Evidence that Essential Oils Affect Puberty” published in the Journal of Reproductive Toxicology also indicates this.

The Data

Three case reports claimed to link lavender and tea tree oil to gynecomastia. However, the authors of these case reports didn’t note the full list of ingredients in the products cited. Neither did they account for xenoestrogenic contaminants including plasticizers, pesticides, and herbicides. Then, in experiments they obtained lavandula officinalis from a chemical company not from an essential oil company. Additionally, to determine if the lavender oil was estrogenic and androgenic in cell culture, they diluted it in DMSO and cultured it in polystyrene plates. Both of these modulate both estrogens and androgens. They also selected to do a cell culture instead of a uterotropic assay (a test to determine if uterine lining grows in response to a chemical). Researchers also widely criticized this because uterotropic assays are considered the gold standard testing method. The authors themselves admit that they needed more research to determine causality.

My Conclusion

In my professional opinion, lavender oil and gynecomastia is a consideration, but would not preclude me from using it on a young male.


UPDATE: There is new evidence! Check out this post for what it is and my thoughts on it.

Want to put your lavender essential oil to use? Check out this blog post.

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