Collagen, biotin, hyaluronic acid, keratin, and the full constellation of beauty supplement ingredients all occupy a compliance gray zone. Their primary appeal is aesthetic — better skin, stronger nails, thicker hair — but the FDA doesn't recognize "aesthetic" as a separate regulatory category. Beauty claims are evaluated as either structure/function claims or disease claims under the same framework that applies to every other supplement.
What FDA Permits for Beauty and Skin Claims
Under 21 CFR 101.93(f), beauty supplements may make structure/function claims that describe how ingredients affect the structure or function of skin, hair, and nails. These are permitted:
"Supports healthy skin"
"Promotes skin elasticity"
"Helps maintain skin hydration"
"Supports healthy hair growth"
"Promotes nail strength"
"Supports collagen production"
"Helps maintain the structure of skin and connective tissue"
"Promotes a healthy appearance of skin, hair, and nails"
These claims work because they describe support for normal structure and function in healthy individuals.
Where Beauty Claims Become Drug or Disease Claims
Prohibited territory for beauty supplements:
"Treats eczema" — named skin disease
"Reduces acne" — acne is a disease condition; treatment claims require drug approval
"Reverses signs of aging" — "reverses" implies treatment of a disease state (the FDA considers pathological aging-related skin changes to be disease-adjacent)
"Repairs sun-damaged skin" — damage repair implies treatment of a condition caused by injury
"Treats psoriasis or rosacea" — named skin diseases
"Clinically proven to reduce wrinkles" — wrinkle reduction has been treated as a drug claim in FDA enforcement actions against cosmetic products
"Repairs the skin barrier" — barrier dysfunction is associated with specific skin disease states
The anti-aging line
"Anti-aging" claims are among the most heavily scrutinized in the beauty supplement space. The FDA has generally treated claims about reversing visible signs of aging as drug claims — the logic being that the claim implies the product is changing skin structure, not just supporting normal function.
"Promotes youthful-looking skin" may be defensible as a structure/function claim when it describes support for normal skin function. "Reverses the signs of aging" implies structural change — and is more likely to be treated as a drug claim. The distinction is between maintaining and reversing.
The Supplement vs. Cosmetic Distinction
Beauty supplements face an additional compliance layer: the supplement/cosmetic boundary. A product is a dietary supplement if it's intended to affect the body's structure or function when ingested. A product is a cosmetic if it's intended to alter appearance when applied topically. If a beauty product is both ingested and applied, it may be subject to both drug and supplement regulations.
Some collagen brands sell their products with accompanying topical application instructions or claim both internal and topical benefits. These products may inadvertently qualify as both cosmetics and supplements — or in some cases, as unapproved drugs — depending on the full scope of claims made.
Collagen Bioavailability Claims
A growing area of marketing for collagen supplements involves claims about bioavailability — that hydrolyzed or specific molecular weight collagen peptides are more bioavailable than others. These comparative claims require substantiation at the FTC's competent and reliable scientific evidence standard.
Claims like "our collagen is 40% more bioavailable" are quantitative outcome claims that require well-controlled human clinical evidence showing that specific superiority for your specific product. General ingredient category research doesn't substantiate a specific superiority claim for your formulation.
Biotin: A Claim Category With Real FDA Scrutiny
Biotin claims for hair and nail health are among the most popular in the beauty supplement space — and among the most commonly over-claimed. The clinical evidence for biotin supplementation's effects on hair and nail health in individuals who are not biotin-deficient is limited.
Under 21 CFR 101.93(a)(3), the structure/function claim notification requires certification that the brand has substantiation that the claim is truthful and not misleading. For biotin, the substantiation question is: does the evidence support the claim for a general healthy adult population, or only for individuals with biotin deficiency? If the evidence primarily supports benefits in deficient populations, a general claim about hair and nail health for all consumers may overstate the evidence.
Beauty claims need the same rigor as any other supplement category
The beauty supplement category's rapid growth has created a culture of claim inflation — products making dramatic skin, hair, and nail claims that push well past what the evidence and regulations support. Truli scans collagen and beauty supplement claims against 21 CFR 101.93's structure/function framework and flags disease-adjacent language, comparative claims without adequate substantiation, and anti-aging language that crosses into drug claim territory.
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.
