No, human growth hormone (HGH) is not a steroid. Despite being grouped alongside steroids in conversations about performance enhancement, HGH and anabolic steroids are fundamentally different substances with different chemical structures, different origins in the body, and different mechanisms of action. The confusion is understandable because both are injectable hormones associated with muscle growth, but the similarities largely end there.
Why HGH Is Not a Steroid
The distinction comes down to basic chemistry. HGH is a peptide hormone, meaning it’s a chain of 191 amino acids (the building blocks of protein). It’s produced by the pituitary gland at the base of the brain. Steroid hormones, by contrast, are lipid-based molecules derived from cholesterol. Your body synthesizes steroids primarily in the adrenal glands and the gonads (testes or ovaries). Testosterone, estrogen, cortisol, and their synthetic derivatives are all steroids. HGH belongs to an entirely different chemical family.
This isn’t just a technicality. The chemical difference determines how each hormone works inside your cells. Anabolic steroids are small, fat-soluble molecules that pass directly through cell membranes, enter the nucleus, and bind to androgen receptors to influence gene expression. That’s how they ramp up protein synthesis and muscle growth. HGH can’t do this. As a large peptide, it can’t cross cell membranes on its own. Instead, it binds to receptors on the outside of cells, triggering a signaling cascade that ultimately stimulates the liver to produce another hormone called IGF-1 (insulin-like growth factor 1). IGF-1 then activates pathways that promote cell growth, protein synthesis, and tissue repair throughout the body.
How HGH and Steroids Differ in the Body
Both HGH and anabolic steroids can increase muscle mass, which is why they get lumped together. But they accomplish this through very different routes, and their broader effects on the body diverge significantly.
Anabolic steroids are synthetic versions of testosterone. They directly boost muscle protein synthesis and reduce muscle breakdown. Their side effects reflect this hormonal profile: the body detects the flood of external testosterone and dials back its own production. This can lead to testicular shrinkage, reduced sperm count, hormonal imbalances, liver damage, acne, and mood changes. In women, steroids can cause masculinizing effects like voice deepening and facial hair growth.
HGH works more broadly. Through IGF-1, it promotes growth in muscle, bone, cartilage, and organs. It also influences fat metabolism, pushing the body to burn fat for energy. But its side effects are distinct from steroids. Misuse of HGH can cause fluid retention, joint and muscle pain, carpal tunnel syndrome, elevated blood sugar (sometimes progressing to diabetes), and high blood pressure. Long-term excess can lead to acromegaly, a condition where bones in the hands, feet, and face thicken abnormally. None of these overlap much with the typical steroid side-effect profile, which further illustrates that the two substances act on different systems.
Legal Classification
The legal treatment of HGH and anabolic steroids also reflects their separation. Anabolic steroids are Schedule III controlled substances under the Controlled Substances Act, placing them in the same regulatory category as ketamine and some barbiturates. HGH is not a controlled substance at all. It sits outside the scheduling system entirely.
That said, HGH distribution is still tightly regulated. The 1990 Anabolic Steroids Control Act (confusingly named, given HGH isn’t a steroid) made it a five-year felony to distribute or possess HGH with intent to distribute for any use other than treating a recognized medical condition under a physician’s order. So while HGH isn’t legally classified as a steroid, Congress chose to restrict its non-medical use in the same piece of legislation that scheduled anabolic steroids.
Approved Medical Uses for HGH
HGH is prescribed for a narrow set of conditions, most of them pediatric. There are currently eight FDA-approved indications for growth hormone therapy in children: growth hormone deficiency, Prader-Willi syndrome, Turner syndrome, Noonan syndrome, chronic kidney insufficiency, being born small for gestational age without catch-up growth, SHOX gene deficiency, and idiopathic short stature (short stature without a known cause). In adults, HGH is primarily prescribed for growth hormone deficiency, which can result from pituitary tumors or damage.
Anti-aging clinics and online sellers sometimes market HGH for muscle building, fat loss, or general rejuvenation. These uses fall outside approved indications, and the evidence for HGH as an anti-aging treatment is weak. The side effects, including diabetes risk and joint problems, make off-label use a meaningful gamble for marginal cosmetic benefits.
Why the Confusion Persists
Several factors keep HGH and steroids tangled in public perception. Both are banned by virtually every major sports organization. Both show up in the same doping scandals. Both are injected. Both are associated with dramatic physical transformations in bodybuilding. And the legislative history ties them together, since Congress addressed both in the same law.
The performance-enhancement community itself often stacks HGH with anabolic steroids, using them in combination. This practical overlap reinforces the idea that they’re the same type of substance. But from a biological standpoint, calling HGH a steroid is like calling a car a motorcycle because both have engines and run on gasoline. They share a general purpose, but the machinery underneath is completely different.