Grapeseed oil is used in skincare products, including those targeting wrinkles, primarily due to its content of antioxidants such as vitamin E, polyphenols (including proanthocyanidins), and essential fatty acids. Several laboratory and animal studies suggest that these compounds may help combat oxidative stress and protect collagen and elastin fibers in the skin, both important for maintaining skin elasticity and reducing visible signs of aging. For example, proanthocyanidins from grape seeds have demonstrated the ability to neutralize free radicals and inhibit enzymes that degrade collagen in vitro and in animal models (source).

Human clinical data, however, is limited. Some small studies and anecdotal reports suggest topical grapeseed oil may improve skin moisture and elasticity, potentially softening the appearance of fine lines, but robust randomized controlled trials specifically examining its effect on wrinkles are lacking. Most evidence for wrinkle reduction is extrapolated from general antioxidant and moisturizing effects rather than direct anti-wrinkle studies.

In summary, the use of grapeseed oil for wrinkles has a scientific rationale based on its antioxidant and emollient properties, but the direct clinical evidence supporting its efficacy for wrinkle reduction in humans remains modest. Thus, the strength of evidence is rated at 2 out of 5.