Shiseido : Discovers New Effect of Improving Neck Wrinkles, Results in 8 Weeks

Shiseido conducted a test to identify the efficacy of retinol in neck wrinkles with 84 Japanese women (age 41-69 years old, mean age 56 years old) in which two groups - one using a cream base with retinol ('retinol group') and one using a base cream with no retinol ('non-retinol group') - applied cream twice daily (morning and evening) to the neck over a 12-week period. Furthermore, a follow-up evaluation was performed 2 weeks after both groups stopped using the cream (14 weeks from the start of the test).
According to the results determined by direct observation (Figure 2), the non-retinol group showed no change in neck wrinkles. On the other hand, the retinol group showed incremental reductions over the duration of the application period, with significant reduction observed after 8 weeks, and additional reduction after 12 weeks. Furthermore, 2 weeks after both groups stopped using the cream, the retinol group saw that marked improvement remained, implying the efficacy of retinol in terms of long-lasting effect and potential to alter the status of wrinkles with non-immediate recurrence.

In addition, according to the results of instrumental replica analysis (Figure 3), the non-retinol group again showed no change, however, the retinol group showed a significant reduction in area percentage of neck wrinkles after 8 weeks and 12 weeks.
Based on the above observation and analysis, it was determined that products containing retinol significantly reduce neck wrinkles, confirming the efficacy of retinol in improving neck wrinkles.

Prior to the application of the cream base with retinol, prominent wrinkles were recognized on the center area of the subject's neck, and after 8 weeks of application, wrinkles appeared lighter and the skin texture was also improved, becoming more smooth across the neck overall. (Figure 4)