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.
At normal levels, estrogen actually helps keep you lean by goosing the production of insulin, a hormone that manages blood sugar. When estrogen gets thrown off, though, it turns you into a weight-gain machine. Here's how: When you eat, your blood sugar rises. Like a bodyguard, insulin lowers it by escorting glucose into three different places in your body.