薬理と治療

Abstract

Background　Previous human studies have demonstrated that collagen hydrolysate improved facial skin conditions. However, there are limited studies which evaluate the effect of long-term ingestion of gelatin on human skin. Methods　The present randomized, double-blind, placebo-controlled parallel-group, comparison clinical study, evaluated 44 post-menopausal（55-65 years old）healthy volunteers. Gelatin group（n＝22）ingested 5 g of gelatin twice daily for 8 weeks. Placebo group（n＝22） ingested 5 g of maltodextrin twice daily for 8 weeks. Measurement of facial skin viscoelasticity and subjective evaluation of skin condition（Visual Analogue Scale╱VAS）were carried out before the first ingestion（0 W）and after 8 weeks（8 W）of ingestion. Results　At the end of the study, there was no association between gelatin ingestion and skin viscoelasticity. Among volunteers whose skin elasticity (R7) is higher than or equal to 0.3 at 0 W, the placebo group (n＝8) showed significant deterioration in R7 value at 8 W (due to environmental factor). On the other hand, the gelatin group (n＝9) showed no remarkable deterioration. Furthermore, variation in VAS score of［dark area in lower part of eyes］was significantly improved in gelatin group（n＝9）but not in placebo group（n＝8）. Conclusion　These results suggested that continuous ingestion of 10 g of gelatin for 8 weeks improved skin viscoelasticity（R7）and skin condition in post-menopausal healthy volunteers with skin elasticity（R7）higher than or equal to 0.3. No side effects were noted throughout the study.