Photoprotection and skin whitening effect of dietary soy milk in healthy young female adults.

Background Topical soy formulations improve signs of aging and protects against ultraviolet light. We aimed to determine photoprotective and whitening effects of oral soy. Methods Healthy volunteers drank commercial soy milk containing 20mg isoflavones twice daily for 8 weeks, and avoided consumption of isoflavone-rich food, sunscreen and lightening products. Phototest and skin colour measurement was performed at baseline and at the end of study. Results Thirty healthy females aged 21(19-22) years with Fitzpatrick skin type III and IV participated. Soy milk significantly increased whiteness at the cheek and gluteal regions. Minimal erythema dose (MED) to UVA increased in 60% subjects, MED to UVB increased in 87%. Significant reduction in UVB induced erythema was observed with all UVB doses, UVA induced erythema decreased with higher doses. Conclusion Short term regular consumption of soymilk showed photoprotection and skin whitening effects. [ABSTRACT FROM AUTHOR]