About Fern extract
A tropical fern extract (standardized as Fernblock) with multiple RCTs supporting oral photoprotection: increased minimal erythema dose, reduced UV-induced erythema, and adjunctive benefit in melasma and actinic keratosis when combined with topical sun protection. It is an adjunct to, not a replacement for, sunscreen.
What Fern extract supports
- May reduce UV-induced skin reddening as an adjunct to sunscreen
- Studied as an add-on in melasma and actinic keratosis
How much Fern extract to take
The RDA prevents deficiency. The effective range is what clinical trials used to actually move the outcome.
Effective
240–480
mg
Photoprotection trials commonly use 240-480 mg/day of standardized extract (Fernblock). Range reflects that clinical use.
Clinical evidence
Moderate clinical evidence. Multiple RCTs for oral photoprotection as a sunscreen adjunct.
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