This is hot off the press!
For those who like to know the latest and greatest on hormone analysis, this is my interpretation of the Lancet study which was published yesterday. Please click on the link below to read the article and statistics for yourself.
The article reveals the effects of estrogen only, progestogen and estrogen daily or intermittently, obesity/BMI, topical vaginal estrogen only and no menopausal hormone therapy on the incidence of breast cancer by the age of 70.
There were over 100,000 women in the study. The study was interestingly a review of several prospective studies which followed women who were treated with or without menopausal hormone therapy for up to 5 years. The conclusions were that hormone therapy even though it was transient in many of these women may have contributed to cancer up to a decade and perhaps longer after stopping the intervention. The study suggests that of the 20 million women diagnosed with breast cancer during that time, it would be estimated that 1 million of those cases are likely due to the contribution of hormone therapy. The devil is always in the details, so one must always be mindful of how the article is interpreted and what variables are used.
Hormone therapy likely increases the incidence of breast cancer to the tune of an association of an additional 1 in 50 women taking menopausal hormone therapy will develop breast cancer.
The study suggests that the group most impacted is found in those women taking progestogen and estrogen daily and being obese.
Obesity is a greater risk factor than taking hormone therapy.
Slightly less risk if taking progestogen intermittently with estrogen
Even lower risk if taking estrogen only
Least risk is associated with those who have a normal weight and do not take hormone therapy
Topical estrogen only for vaginal symptoms was not associated with increase in breast cancer
My interpretation: This study looked at synthetic progestogens and not bio identical hormones. We know that progestogens are similar to progesterone but chemically are not the same. We also know that the typical estrogens used are conjugated equine estrogens, again not bio identical. Conjugated equine estrogens come from “horses,” not humans, and the progestogens, although similar to progesterone are not identical to that which is naturally found in the human body.
Countless times, we have seen that chemicals such as BPA and triclosan can look chemically very similar to other hormones, and as a result have an endocrine disrupting effect. Is this a case with using conjugated equine estrogens and synthetic progestogens? We do not completely know. There are many variables in this study, but it does make me concerned…..
Clearly topical estriol or estrace appears to be safe, as this was quite a large study and no association was found with using it and an increased incidence of breast cancer. .
Clearly progestogens do not appear to be safe.
In addition, maintaining a healthy BMI is likely our best defense in this toxic world, and likely exercise, stress control etc as seen by other studies.
I personally, would like to see the effects of bioidentical hormones, on the incidence of breast disease. Unfortunately, there are a lot fewer users of bioidentical hormone therapy than traditional pharmaceutical hormones. There is no financial incentive to patent these naturally occurring varieties of hormones, therefore, studies to the tune of 100,000 plus individuals are unlikely to ever be seen.
I would also like to know, for those women who are using hormones or not using hormones and following healthy lifestyle regimens, what is their incidence of breast disease. My guess is that those women who exercise, participate in stress reduction and eat an organic healthy plant-based diet, as a population, have a lower incidence of disease.
The big point that this article brings out in my opinion, is the value of individualized medicine. We need to get to know that woman who is sitting across from us as practitioners. We need to meet her where she stands. What are her personal stresses, her physical symptoms, her family history and lifestyle choices. These all play an important role in making the safest and healthiest decisions.
Be wise and be well!