Peptides vs Steroids

How we label evidence

We use plain labels: approved medicine (we name the regulator and the use), established, promising but limited, mixed, insufficient evidence, preclinical (cells or animals only), no good evidence of benefit, evidence of harm, and marketing claim. Where we looked and found nothing usable, we write "Proper evidence not found."

Definitions

A peptide is a short chain of amino acids, typically 2 to 50, joined by peptide bonds. [1] Peptides include hormones such as insulin, approved medicines, cosmetic ingredients and unapproved research compounds. See what peptides are.

Anabolic steroids are synthetic versions of testosterone, the main male sex hormone. [2] Their effects include muscle growth and the development of male sexual characteristics. [3]

The two are different chemical families. Steroid hormones such as estrogen are an example of molecules small enough to pass through the outer membrane of a cell. [4] Many peptides instead act on receptors on the cell surface, but this is a general pattern and each compound has to be checked on its own. See hormones vs peptides.

Where they overlap

Some people hear the two grouped together because both appear in sport and appearance-enhancement talk. The National Institute on Drug Abuse describes insulin, insulin-like growth factor and human growth hormone as "non-steroidal anabolics." They are made by the body, prescribed for medical uses, and sometimes misused for performance. [3] Growth hormone is built from amino acids (191 in its approved form), so it belongs on the peptide and protein side, [5] which means "peptide" and "steroid" are not simple opposites in sport talk. Muscle-building talk can involve either, and neither word tells you whether a product is a medicine.

The difference at a glance

What misuse of steroids has been linked to

MedlinePlus says misuse, especially over a long period, has been linked to acne, high blood pressure, cholesterol changes, heart attack, liver disease including cancer, kidney damage and mood changes. [2] In men it lists infertility and testicular shrinking. In women it lists menstrual changes and voice deepening. [2] It notes that doses used for misuse may be 10 to 100 times those used for medical conditions. [2] NIDA adds that steroids can cause severe, long-lasting and sometimes irreversible damage, and that stopping can cause depression. [3] Evidence label: evidence of harm when misused.