Anabolic Steroids
Anabolic steroids are one kind of hormone. These steroids facilitate building up the body. That's what "anabolism" is, the building up part of the chemical reactions in the body that are, all together, called metabolism. We'll get back to that in a minute.
The steroid part of the name refers to a part of the molecular structure of these hormones. There are other hormones that also have this structure, namely the anti-inflammatory steroids like cortisone, prednisone and medrol. Cortisol (also called cortisone) is made by the adrenal glands, it is entirely different that the steroids that this article is concerned with, yet is popularly confused with them. That's no wonder, when both the anabolic steroids, like testosterone, and the glucocorticoid steroids that are anti-inflammatory, like prednisone, are both most often called just plain "steroids", without any kind of qualifying adjective. There's another reason, too. Both of these entirely different classes of hormones have a couple of major similarities in their effects: 1) they tend to make people feel pretty great at first and 2) with long-term use they both have the potential for deadly side-effects.
The anabolic steroids are made in the human body by at least two different glands, the adrenal glands and the gonads.
In men, the gonads are the testes and in women they are the ovaries. The major anabolic steroid made in the human body is testosterone, and that hormone is made in both men and women, although the amount made in men is much greater. There is another adjective that is commonly used to describe these steroids, and that's androgenic. The meaning of that word is "to make into a man", and that's, esentially, true. The secondary sex characteristics that are masculine all pretty much develop in response to the androgenic hormones. The heavy musculature, the beard, the pattern of the pubic hair- these are all the result of testosterone (and testosterone-like hormones) on the body.
Outlawed in Sports
The use of these hormones as aids to body building and atheletic performance have been banned in sports for several reasons. One of these reasons is the detrimental health effects that have become apparent with their use. There is evidence that the use of anabolic steroids may actually cause a form of dependency, animal studies have shown that male and female hamsters will voluntarily self-administer testosterone and other anabolic steroids, even to the point of fatal overdose. These results have led researchers to conclude that the substances are potentially addictive, "independent of their effects on muscle mass or athletic performance". (reference:Ruth I Wood: Anabolic Steroids: A Fatal Attraction? Journal of Neuroendocrinology, Volume 18, Issue 3: 227-228. doi: 10.1111/j.1365-2826.2006.01407.x)