Many steels add to the iron-steel mix other metals that give the entire substance desirable properties such as strength, heat resistance, or flexibility. Steel is considered a mixture rather than a compound because the iron does not chemically bond with the carbon and other components.
Some of estrogen's effects include: 1  Increasing serotonin, and the number of serotonin receptors in the brain. 2  Modifying the production and the effects of endorphins, the feel-good chemicals in the brain. 3  Protecting nerves from damage, and possibly stimulating nerve growth.
Side Effects. Women rarely have severe side effects from taking estrogens to replace estrogen. The prolonged use of estrogens has been reported to increase the risk of endometrial cancer (cancer of the lining of the uterus) in women after menopause. This risk seems to increase as the dose and the length of use increase.