Given that it's made up of 96 percent water, a cucumber is expected to moisten when put on the eye. The moisture helps hydrate the skin around the eye, leading to fewer stretch marks and wrinkles.
For the best effect, store the cucumber in the refrigerator first before applying on the eyes. Cut two thick slices, and set them on the closed eyes for at least 10 minutes. Along with the cucumber's hydrating effect, the cool temperature helps reduce blood flow and therefore eases any swelling or eye puffiness. Cucumbers are also known for their antioxidant and flavonoid properties that help alleviate skin irritation.