TITLE:
Gluconacetobacter hansenii GK-1 Ingestion for 8 Weeks Improves Skin Discomfort in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study
AUTHORS:
Mariko Oe, Mengwei Yuan, Keiko Kuriyama, Yumi Takeda, Mamoru Kimura, Ryosuke Matsuoka, Naoki Miura, Jun Muto
KEYWORDS:
Acetic Acid Bacteria, Ingestion, Skin Itch, Paraprobiotics, Functional Food
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.15 No.11,
November
14,
2024
ABSTRACT: Gluconacetobacter hansenii GK-1 is an acid-resistant gram-negative bacterium used in vinegar brewing. Oral ingestion of GK-1 was previously reported to help maintain immunity and reduce nasal discomfort. Considering the suggested mechanism of action of activation of regulatory T cells via TLR4 to control Th1/Th2 balancing, GK-1 is also assumed to reduce skin discomfort secondary to immune reactions; however, this has not been validated in humans. Thus, we conducted a randomized, double-blind, placebo-controlled, parallel-group study on 100 healthy Japanese men and women (mean age, 47.6 ± 1.01 years) aged 20–64 years who consumed GK-1 (9 × 109 cells) daily for 8 weeks. Visual analog scale for overall, facial, arm, and leg skin discomfort was assessed before and after ingestion. The cumulative days of skin discomfort during the ingestion period were assessed. Compared with the placebo group, the G. hansenii GK-1 group had a significantly lower visual analog scale for overall and facial skin discomfort after 8 weeks and cumulative days of skin discomfort. Moreover, there were no adverse events attributable to G. hansenii GK-1. This study confirmed that oral ingestion of G. hansenii GK-1 contributed to skin integrity. The study protocol was preregistered at the Clinical Trials Registry System (registration no. UMIN000053005, December 7, 2023).