What are steroid hormones?

First of all, what are hormones? Hormones are chemical substances produced by the body, and functioning as a messenger between organs. There is usually an organ that produces and an organ that receives. You can think of hormones as the wireless counterpart of the nervous system. It connects parts of the body remotely, to give them various orders; and it is much slower than the wired nervous system. Some common and known hormones that act as neurotransmitters are dopamine, serotonin, oxytocin, melatonin… Closer to our topics, we find the GnRH (Gonadotropin Releasing Hormone), FSH (Follicle Stimulating Hormone) and LH (Luteinizing hormone). Those last three, as we’ll see, play an important role in controlling sex hormones, and we’ll see what we can do with that.

So, the hormones that interest us here, the “sex hormones” - estrogens, androgens, and progestogens - are steroids that act as hormones. That’s why we call them steroid hormones. And those three groups - androgens, estrogens, and progestogens - are only three among five subgroups of steroid hormones; the two other being glucocorticoids (like cortisone and cortisol - the so-called stress hormone), and mineralocorticoids. We don’t need to know about those two here.

So what are steroids, and what do they have to do with “steroids” used by some bodybuilders and intense sportspeople (you know, -“this guy is buying steroids online, he wants to grow bigger and bigger!) ? Well, the products that these sportspeople use are part of the same group of molecules called steroids - and they are grouped together because of their particular molecular composition and organization, and the way they interact with their target cells. Steroids used in sports are a subgroup of steroid hormones called anabolic steroids, and it includes “natural” androgens like testosterone, but many other synthetic androgens. Anabolic steroids are all androgenic - various molecules similar to testosterone, and activating the androgen receptors -, but we chose here to speak of anabolic steroids to designate both “natural” (biosynthesized, naturally present in the body) and synthetic androgenic hormones (including the one used and abused in sport); and androgens to designate only the bioidentical molecules produced by the body (mainly testosterone and DHT).

But, yes, if you get estrogen treatment to grow boobs, then you can say that technically, you’re taking steroids. Not anabolic, but steroid still.

But let’s keep it simple and call them hormones, because they act just like hormones.