The testosterone supplement category sits at a particularly sensitive regulatory intersection. Testosterone itself is a controlled substance when used as a drug. Supplements claiming to increase testosterone are not drugs — but when their marketing implies they treat testosterone deficiency (a medical condition), the FDA treats them as unapproved drugs.
What FDA Permits for Testosterone and Hormone Claims
Under 21 CFR 101.93(f), supplement labels may make structure/function claims about supporting hormone balance and normal testosterone levels within the healthy range. These are generally permissible:
"Supports healthy testosterone levels"
"Promotes testosterone within the normal range"
"Supports healthy hormone balance"
"Promotes healthy male vitality"
"Supports healthy energy and stamina"
"Promotes healthy libido"
"Supports healthy muscle and strength maintenance"
The critical qualifier in all of these is the implication of supporting normal function in healthy adults — not correcting a deficiency or treating a clinical condition.
Where Testosterone Claims Cross the Line
Prohibited disease claims:
"Treats low testosterone" — low testosterone (hypogonadism) is a diagnosed medical condition
"For men with Low T" — "Low T" is a lay term for hypogonadism, a named disease under 21 CFR 101.93(g)(2)(ii)
"Restores testosterone levels to normal" — "restores" implies correcting a deficient state (disease treatment)
"Reverses testosterone decline" — decline implies a disease state; reversal implies treatment
"Increases testosterone by 40%" — specific quantified outcome claims require FTC-standard clinical evidence
"Helps with symptoms of testosterone deficiency" — explicit disease symptom reference
"Improves erectile dysfunction" — named condition; treatment claims require drug approval
"Treats andropause" — referenced as a male equivalent to menopause; FDA has treated references to this condition as disease claims
The "Low T" marketing problem
"Low T" became ubiquitous in testosterone supplement marketing after pharmaceutical testosterone replacement therapy campaigns popularized the term. Using "Low T" in a supplement context — "formulated for men with Low T" or "address the symptoms of Low T" — is essentially citing a disease diagnosis in your marketing. Under 21 CFR 101.93(g)(2)(ii), referencing the characteristic signs or symptoms of a disease using lay terminology constitutes a disease claim.
Ingredient-Level Issues
Many testosterone supplement ingredients have limited clinical evidence for effects on testosterone levels in healthy men with normal testosterone. For these ingredients, even structure/function claims must be carefully calibrated:
Ashwagandha (KSM-66): Has some clinical evidence for effects on testosterone in stressed or physically active populations. Claims should reflect the population in which evidence exists.
Fenugreek: Mixed evidence. Some studies show effects on free testosterone; others don't. Claims should reflect the totality of the evidence.
Zinc and vitamin D: Clear roles in testosterone metabolism — deficiency in either is associated with lower testosterone. Claims about supporting healthy testosterone levels may be substantiated, particularly for products targeting potential deficiency.
D-Aspartic Acid: Evidence for short-term effects in some populations. Long-term evidence is weaker.
Tribulus terrestris: Clinical evidence does not consistently support testosterone effects. Claims about testosterone effects for this ingredient are difficult to substantiate.
The Prohormone and SARM Problem
The testosterone supplement category has a history of products containing prohormones (androstenedione, DHEA analogs) or selective androgen receptor modulators (SARMs) that are not legal dietary supplement ingredients. Prohormones have been specifically prohibited by the Anabolic Steroid Control Act. SARMs are investigational drugs not approved for marketing as dietary supplements.
Marketing a product containing these compounds as a dietary supplement — regardless of the claims made — is a legal violation independent of the labeling. If your product is in the testosterone support space, the ingredient review needs to go beyond claim compliance.
Testosterone claims require label, ingredient, and marketing compliance simultaneously
The testosterone supplement category faces enforcement from multiple directions: disease claims on labels, unsubstantiated advertising claims, and sometimes illegal ingredients. Getting compliant in this category means reviewing all three layers — claims, substantiation, and ingredient legality. Truli's product scans surface disease-adjacent testosterone claims and flag language that implies treatment of hypogonadism or testosterone deficiency.
A note from Truli: Truli is not a law firm, and this article does not constitute or contain legal advice or create an attorney-client relationship. When determining your obligations and compliance with respect to relevant laws and regulations, you should consult a licensed attorney.
