Estrogen Metabolism: A Key Factor in Breast Cancer Risk Assessment
October is breast cancer awareness month. One aspect of breast cancer risk that is not discussed frequently is estrogen metabolism. This is not only important in women on bioidentical hormone restoration therapy, but also for young women who are exposed to endogenous estrogen, the estrogen their bodies make every day. This estrogen has to be metabolized just like any other hormone in the body.
The metabolism of estrogen involves two main competing pathways: 2-hydroxy estrone and 10-hydroxy estrone. There is one minor pathyway, 4-hydroxy estrone. Confused yet? It will become much clearer in a moment.
2-hydroxy estrone is considered the “good estrogen” in that it does not stimulate cell growth and is considered “anti-cancer”. The caveat is that phase two detoxification pathways are intact and healthy. This is called methylation and is measured in the 2-hydroxy estrone to 2-methoxy estrone ratio. These are simply urine tests. Factors that promote healthy methylation are SAMe, methionine, Vitamin B2, B6, B12, folic acid (in activated form), trimethylglycine, and reducing stress.
Studies show that 16-hydroxy estrone may increase the risk for breast cancer. High levels are associated with obesity, hypothyroidism, pesticide toxicity (organochlorines), omega-6-fatty acid excess, and inflammatory cytokines. The ratio of 2-hydroxy estrone to 16-hyroxy estrone is an important indicator of the potential cancer risk of a particular individual.
4-hydroxy estrone directly damages DNA and may be associated with an increased risk for breast cancer. Equine estrogens such as Premarin increase metabolism into 4-hydroxy estrone. Women with uterine fibroids often have elevated 4-hydroxy estrone levels. Methylation is important here as well as 4-hydroxy estrone can be methylated to 4-methoxy estrone which renders it inactive.
Basically we want more metabolism down the 2-hydroxy estrone pathway. We can accomplish this through moderate exercise, cruciferous vegetable intake, flax, soy, high protein diet, indole-3-carbinol, di-indolemethane, omega-3 fatty acids, B6, B12, folate, trimethlyglycine, rosemary, turmeric, weight loss (obesity decreases 2-hydroxy estrone). Reducing one’s exposure to xenoestrogens is also critical. Xenoestrogens are found in pesticides, synthetic hormones fed to animals, plastics, and cosmetics. Reducing alcohol intake is also important as alcohol interferes with the body’s ability to detoxify estrogen.
All of these pathways can be easily tested with a simply urine test. Call one of our offices to set up an appointment to discuss your risk and have your pathways tested today.