A Single-center, Double-blinded, Randomized, Placebo-controlled Trial Evaluating the Safety and Efficacy of a Dietary Supplement Containing Rosemary Extract on Visible Facial Skin Quality.

Abstract

Objective: Glycative stress promotes the accumulation of advanced glycation end products (AGEs), impairing extracellular matrix proteins and accelerating skin aging. Rosemary extract has been shown to deglycate AGE crosslink proteins. The safety of a dietary supplement containing rosemary extract (BioR) and its efficacy on skin quality parameters was evaluated over 12 weeks.

Methods: The randomized, double-blinded, placebo-controlled trial included female participants, aged 40 to 65 years, with moderate-to-severe skin dullness and roughness/texture, and mild-to-moderate erythema, pore size, and uneven pigmentation based on a six-point grading scale. Subjects were randomized to either BioR (n=52) or placebo ([PLB] n=52). The dosing schedule was as follows: from Weeks 1 to 4, two capsules three times daily; from Weeks 5 to 8, two capsules twice daily; from Weeks 9 to 12, one capsule twice daily. Capsules were taken with food. Investigator assessments occurred at baseline and Weeks 4, 8, and 12. Global skin quality (total sum of scores) and adverse events (AEs) were recorded over 12 weeks.

Results: Mean age, severity and baseline demographics of subjects were similar across groups. Significant mean improvements in BioR versus PLB were observed in skin dullness (p=0.04), roughness/texture (p=0.001), erythema (p=0.05) and pore size (p=0.04) at Week 12. No significant differences occurred in uneven pigmentation. Significant mean improvements in global skin quality were demonstrated in BioR versus PLB at Weeks 8 (p<0.0001) and 12 (p=0.002). One subject (BioR) discontinued at Week 4 due to possibly related, moderate gastrointestinal upset.

Conclusion: Following 12 weeks of use, a dietary supplement containing rosemary extract and its natural cofactors led to significant mean visible improvements compared to placebo in skin dullness, roughness/texture, erythema, and pore size, and was well tolerated.