For the Love of Science, Can We Stop the Chit-Chat on Lavender, Tea Tree, and Man Boobs?!
I received a few emails asking my take on this latest media scare story featuring essential oils’ questionable safety. Since this subject of essential oils acting as endocrine disruption seems to keep surfacing, I decided to edit and expand on my response for all my subscribers. First, I will give you the bare-bones, easily-understandable explanation. Following this, I will go into more details for the more scientifically inclined and/or curious.
Q: Did you see the study that tea tree and lavender oil are estrogenic? Should I be concerned?
I read the summary of findings as presented by the Endocrine Society at their annual meeting and reported by Science Daily. I do not have the full details since the published paper was not released yet, but its results appear to be very poorly reported on and not fully based on the actual findings. The conclusions of the study are extrapolated from an in vitro experiment assessing isolated constituents from lavender and tea tree essential oils.
In the study, researchers extracted components deemed to be important in these essential oils and analyzed the hormonal changes. These endocrine effects were inferred by measuring the resulting estrogen receptor- and androgen receptor-target genes and transcriptional activity. This was done on human cancer cells, not in animals or humans.
In an article reviewing the safety of lavender oil in pregnancy, Robert Tisserand states how in vitro effects can be inconclusive:
One in vitro study found that lavender oil had a very weak estrogenic action in MCF-7 breast cancer cells (Henley et al 2007). However, there is no evidence that lavender oil has any adverse effects on human hormonal activity. In another in vitro study, lavender oil inhibited the growth of MCF-7 cells (Zu et al 2010) suggesting that, while it may bind to estrogen receptor sites in the body, it is not an estrogen mimic, and so does not promote estrogen.
Furthermore, the effects in a living system cannot be assumed to be the same as in a petri dish.
For example, in a 2008 study, Evaluation of the developmental toxicity of linalool in rats, the authors stated, “It is concluded that linalool is not a developmental toxicant in rats at maternal doses of up to 1000 mg/kg/day.” (Int J Toxicol. 2008 Mar-Apr;27(2):183-8.)
Here is more on this subject from a previous fear-promoting, misleading headline from a recent blog.
But I don’t Want to Have “Man Breasts”
Guys may be wary of using certain essential oils because they have heard the rumors that lavender and tea tree cause gynecomastia, breast growth in males.
Let me put your mind at ease.
That’s actually not true for many reasons.
The “lavender” and “tea tree” that were blamed in these cases were not validated as therapeutic quality essential oils. Furthermore, a few of the studies combined the oils with endocrine disruptors, chemicals associated with estrogenic effects, in personal care products! You can get the details in this short blog I wrote here.
Pure essential oils are modulators that bring the body’s hormones into balance, rather than specifically acting to increase estrogen (“estrogenic”). Certain oils may promote more estrogen balance, but the “estrogen environment” is the determinant of their effect. I will go back to this topic at a later date.
I hope you will apply this information to empower you with your use of essential oils for relationship health, emotions, hormones, and libido.
In Part II, I will explore factors in male infertility and highlight studies with essential oils that may be usual to those couples struggling with this condition. (This blog shows how essential oils help balance and promote male reproductive health!)
The Bottom Line and a Few More Considerations
The bottom line is that isolating constituents and measuring their effect in cells is a completely different study than assessing an essential oil in human beings.
Another issue is that essential oils in their whole form were not tested, nor were they used as a comparison. The authors’ conclusion would have been more accurately reported to be based on the substances assessed, not generalizing to essential oils. This is due to the fact that essential oils have synergy, there is a balancing effect.
For example, one compound that may act on estrogen receptors may be balanced by another one that is present. Also, natural compounds act different than synthetic compounds on hormonal receptors. Furthermore, the environment of the essential oil and metabolomics of the individual impact its effect. I explain more of these details and the nitty gritty on my homepage.
Click here to read, “The Continuation of the Controversy: In Defense of Essential Oils Synergy and Intelligent Design”
Many blessings from my heart to yours!
This material is for information purposes only and is not intended to diagnose, treat, or prescribe for any illness. You should check with your doctor regarding implementing any new strategies into your wellness regime. These statements have not been evaluated by the FDA. (Affiliation link.)
Disclaimer: This information is applicable ONLY for therapeutic quality essential oils. This information DOES NOT apply to essential oils that have not been tested for purity and standardized constituents. There is no quality control in the United States, and oils labeled as “100% pure” need only to contain 5% of the actual oil. The rest of the bottle can be filled with fillers and sometimes toxic ingredients that can irritate the skin. The studies are not based solely on a specific brand of an essential oil, unless stated. Please read the full study for more information.