What It Is Used For Grape seed extract is used for conditions related to the heart and blood vessels, such as atherosclerosis (hardening of the arteries), high blood pressure, high cholesterol, and poor circulation. Other reasons for the use of grape seed extract include complications related to diabetes, such as nerve and eye damage; vision problems, such as macular degeneration (which can cause blindness); and swelling after an injury or surgery. Grape seed extract is also used for cancer prevention and wound healing.