Monday, September 06, 2004
Progesterone News
I often hear people say that they can't use natural progesterone cream because they have had breast cancer and their tumors were estrogen and progesterone positive. This always concerned me because all of the research I have found did not link bio-identical progesterone to breast cancer, but rather showed it had a positive effect on tumors. Dr. David Zava, breast cancer researcher explains this the best:
"In cancer cells that contain progesterone receptors, progesterone should slow the growth of cancer and push it towards a more differentiated state. This progesterone-induced differentiation requires cell division so it is possible that progesterone was allowing the cancer cells to proliferate and differentiate (specialize) simultaneously. On the other hand it is possible that breast cancer cells did not contain progesterone receptors, which would prevent them from responding to the anti-estrogenic actions of progesterone (ie, progesterone down-regulates estrogen receptors and desensitizes tissues to further growth-promoting actions of estrogens). It is also possible that a progesterone cream is of insufficient strength to have full-anti-estrogenic effects. Low dose progesterone works in synergy with estradiol to stimulate growth and proliferation. "
This is why it is important to know your progesterone cream. Be sure you use a USP progesterone that contains 480-500 mg per oz. The cream should be botanically-based so that the progesterone is allowed to absorb into the skin. Do not use creams with lanolin, wax or petroleum (mineral oil) bases. Do not apply to skin that has been moisturized with creams that contain lanolin, wax or petroleum as well. These act as a barrier and will prevent penetration of the progesterone into your skin. Formulation is everything!
"In cancer cells that contain progesterone receptors, progesterone should slow the growth of cancer and push it towards a more differentiated state. This progesterone-induced differentiation requires cell division so it is possible that progesterone was allowing the cancer cells to proliferate and differentiate (specialize) simultaneously. On the other hand it is possible that breast cancer cells did not contain progesterone receptors, which would prevent them from responding to the anti-estrogenic actions of progesterone (ie, progesterone down-regulates estrogen receptors and desensitizes tissues to further growth-promoting actions of estrogens). It is also possible that a progesterone cream is of insufficient strength to have full-anti-estrogenic effects. Low dose progesterone works in synergy with estradiol to stimulate growth and proliferation. "
This is why it is important to know your progesterone cream. Be sure you use a USP progesterone that contains 480-500 mg per oz. The cream should be botanically-based so that the progesterone is allowed to absorb into the skin. Do not use creams with lanolin, wax or petroleum (mineral oil) bases. Do not apply to skin that has been moisturized with creams that contain lanolin, wax or petroleum as well. These act as a barrier and will prevent penetration of the progesterone into your skin. Formulation is everything!
