Earlier this year a patient came to me worried about an article she had seen from the University of Kansas Cancer Center – it discussed the implications of progesterone in breast cancer. Of course for women when we hear any hormone mentioned in connection it immediately brings back all sorts of misinformation we learned over the years.
Let me clear a few things up. The women were NOT taking progesterone, the serum levels that were tested were on menopausal women not taking HRT. Here’s the thing…. Anyone who knows anything about menopausal women knows that our progesterone tanks the second our ovaries shut down. SO what was tested would have been the teensiest of amounts.
Remember that the quality of a study is important, if I have learned nothing else I have learned the importance of this fact. So since this was a baseline association study, its conclusions were trash, worse than trash – they were worthless. It doesn’t prove causation. But to anyone who wants to grasp at the preverbal straw… or to someone who can’t interpret data to save their life… it might look scary. Sadly some researchers took the bait and we are right back where we were with the estrogen vs estradiol debate.
I also like to follow the money trail, cause what benefit would a cancer treatment centre have in making such statements? Other than the discovery and marketing of new drugs. I mean if estrogen blockers are so popular then maybe progesterone blockers would make them some coin too? But they would have to prove that it was needed.
There was ZERO proof by these researchers from this study or any other literature, that could show harm from prescribed progesterone or increased cancer risk. There were NO randomized control studies, not one. In fact, the studies that have been done as well as the literature that is out there show not only does progesterone supplementation DECREASE breast cancer risk, it decreases incidence.
Tinney, et. al., published in Nature Reviews Cancer – shows the benefits of P4 (progesterone) in TREATING breast cancer…When successfully utilized as a treatment for ACTIVE breast cancer how can these researchers also be saying it creates risk?
That’s 20 years of data btw.
That’s 20 years of research.
Research that very clearly demonstrates the protective benefits of P4 in preventing breast cancer – it’s why I am such a fan of oral, micronized progesterone for my patients. Topicals just don’t add that kind of protection.
Ok so I mentioned earlier about progesterone blockers… and here it is. If estrogen blockers have such incredible *cough* effects on breast cancer then wouldn’t the discovery of a progesterone-receptor blocker be just as beneficial – they summarized this. There is no such current drug might I add. What we do have is progesterone receptor blockers called progestins (yup the synthetic stuff I preach about avoiding). You can read about the science below:
We know the RR of those blockers (progestins) for breast CA:MPA is 1.7 and norethindrone 2.1, whereas the RR for P4 (progesterone) averages 0.8
Cancer journals cited by Dr Neil Rouzier
The bottom line is Association Does Not Prove Causation!
