Oral N-acetylglucosamine supplementation improves skin conditions of female volunteers: Clinical evaluation by a microscopic three-dimensional skin surface analyzer

Summary Within the skin ti ssues, acidic mucopolysaccha rides such as hyaluronic acid are present in the co­ rium layer and play a large part in water retenti on and skin resili ence. Hyalu ronic acid is a po lymer composed of dimers conta in ing N-acetylglucosamine and g lu curonic acid . Although appli cati ons o f the use of hyaluronic acid in cosmeceutical food ha ve been reported, the beauty efficacy o f ora ll y­ ingested hyaluronic acid cannot be predicted adequate ly because li ttle is known about its digestio n and absorpti on in humans. The purpose of thi s study was to in vesti gate the effect of long-term ora! N-acetylglucosamine sup­ plementati on on skin condi tions in fe ma les who have a common tende ncy of xeroderma and rough skin. The subjects (average age: 25.5 ± 10.7) were assigned rando mly and double -blind to e ither a N-acetylglucosamine group (n= l l ) or a placebo gro up (n= 11 ), and in gested a dail y I 000-mg dose of N-acetylglucosamine or lactose, respecti vely, for 60 days. Dermato logica( examinati on by doctors suggested that N-acetylglucosamine supple mentati on favo­ rabl y affects skin conditi ons; th at is, improvements were observed in the desiccation of fac ial and who le body skin. After N-acetylglucosamine supple me ntation fo r 60 days, che moisture conte ne o f the regio n below the le ft eye was incre ased signifi cantly; conversely, a sig nifi cant decrease in the oil a nd fa t content was observed. [n addition, cl ini cal evalu ation by a microscopie three-dimensio nal ski n surface a nalyzer confirmed that oral N-acetylg lucosami ne supplementati on is useful for mi tiga­ ting the roughness o f the ski n and che epidermolys is of the corneum. T hese results indicate tha t oral N-acetylglucosamine supple mentation may be of be ne fi t in enhanc ing skin hydration. By contrast, no sig nificant improvement was observed in the skin condition of the placebo gro up, as appra ised by either dermatological examination or digita i analys is. The beautificati on effect produced by inge­ stion of N-acetylglu cosamine ind icates that th is compound may be a pote ntia l ingredient fo r cosme­ ceutical foodstuffs.