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.
Estrogen is a normal and essential hormone for both women and men, but the more estrogen there is circulating in the blood, the greater the driving force behind some kinds of breast cancer. When women adopt a low-fat diet, their estrogen levels drop noticeably in a very short time.