Source comparison
Melanotan-2 Tanning vs DHA Bronzers vs Oral Carotenoids: Mechanism Comparison
Active pathway MC1R receptor agonist → cAMP → MITF → tyrosinase upregulation → eumelanin synthesis in melanosomes Non-enzymatic Maillard reaction between DHA and amino acids in stratum corneum → brown melanoidin polymers (not melanin) Lipophilic carotenoid dep
This comparison does not assign a generated winner or score.
- Active pathway
- MC1R receptor agonist → cAMP → MITF → tyrosinase upregulation → eumelanin synthesis in melanosomes
- Non-enzymatic Maillard reaction between DHA and amino acids in stratum corneum → brown melanoidin polymers (not melanin)
- Lipophilic carotenoid deposition in subcutaneous adipose tissue and stratum corneum. No melanin involved
- Only MT-2 produces true melanin; DHA is a surface stain; carotenoids are pigment storage
- Photoprotection
- Yes. Eumelanin absorbs UV radiation and scavenges reactive oxygen species; SPF equivalent 2–4 based on reflectance spectroscopy
- No. Melanoidins do not absorb UV meaningfully; clinical studies show no reduction in MED (minimal erythemal dose)
- Minimal. Beta-carotene has weak singlet oxygen quenching but no UV absorption; no MED increase documented
- MT-2 provides genuine photoprotection; DHA and carotenoids are cosmetic only
- Duration after cessation
- 60–90 days (dependent on epidermal turnover and maintenance dosing)
- 5–10 days (exfoliates as stratum corneum sheds)
- 14–21 days (adipose stores deplete as carotenoids are metabolised)
- MT-2 persistence matches keratinocyte lifespan; DHA is shortest; carotenoids intermediate
- Injection requirement
- Yes. Subcutaneous injection required for bioavailability (peptide degraded in GI tract if oral)
- No. Topical application only
- No. Oral capsules
- MT-2 requires sterile injection technique; DHA and carotenoids are non-invasive
- Fitzpatrick type responsiveness
- Types II–IV respond best; Type I requires extended loading; Type V–VI see minimal change (already high baseline melanin)
- All skin types (surface reaction, not melanogenesis)
- All skin types but more visible on fair skin due to contrast
- MT-2 efficacy is melanocyte-dependent; DHA works universally; carotenoids show best in pale skin
- Regulatory status (2026)
- Not FDA-approved; research use only; banned for cosmetic sale in Australia, UK
- FDA-approved as cosmetic colorant; GRAS status
- FDA-approved dietary supplement (Vitamin A precursor)
- MT-2 remains unregulated for tanning; DHA and carotenoids are legal consumer products