Evaluation, in vivo on human subjects, of the anti-aging effect of SoyLife EXTRA versus placebo

Frutarom, by Dermscan Laboratoires, France, 2000.

Skin aging occurs under intrinsic and extrinsic influences, such as changes in estrogen production and exposure to free radicals. During and after menopause, falling estrogen levels cause a decrease in general skin tone, wrinkles and sagging. Aging skin tissue typically stiffens and loses elasticity. SoyLife was incorporated in a standard cream (1.6% of SoyLife EXTRA, i.e. 0.18% isoflavones) and tested on healthy menopausal women.

Anti-wrinkle effect

The study was performed on two groups of each 10 healthy menopausal women (45-65 yrs) with problems linked to menopause. One group used the SoyLife cream and the second a placebo cream. The subjects were told to use the cream twice a day for 8 weeks. On day 0 silicone prints of the crow’s foot were taken from each subject. New silicone prints were taken on day 28 and day 56. The antiwrinkle effect was measured using Skin Analyzer and Quantirides software.

After day 28 the SoyLife cream significantly reduced the number of deep wrinkles by 24% (see graph). This effect was maintained at 22% after 56 days. The placebo group did not show a significant effect.

Cutaneous microcirculation

In this test 10 healthy menopausal women used the standard cream with SoyLife EXTRA, twice a day for eight weeks. On day 0 and on day 56 cutaneous microcirculation (skin blood flow) was measured by a Laser Doppler on the cheeks of the subject. Results show that after using the SoyLife cream the skin blood flow decreased significantly after eight weeks with 36.5%. SoyLife EXTRA can therefore be used in creams to calm skin redness and sensitive skin as well as to improve skin radiance.

Sensory evaluation

The aim of this evaluation was to determine the cosmetic acceptance of the cream with SoyLife EXTRA. The women completed a subjective questionnaire regarding tolerance, organoleptic parameters and product efficacy. After 56 days of twice daily application the results were positive. The SoyLife cream was well accepted. Particularly good tolerance, high efficacy and very pleasant sensations were reported.