Three incidents of abnormal breast development in young boys have been attributed to the regular use of lavender and tea tree oils. The condition was reversed once use of the products was stopped.
These essential oils can be found in some soaps, shampoos, hair gels and body lotions. Laboratory testing has shown both lavender oil and tea tree oil can mimic the action of the female hormone oestrogen and block male hormones that control both masculine characteristics and inhibit the
growth of breast tissue.
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