OPCs are a class of very powerful plant bioflavonoids. Their powerful antioxidant property makes grape seed extract an excellent remedy in the prevention of cardiovascular diseases, arteriosclerosis and arthritis. Proanthocyanidins inhibit the synthesis of hormones such as histamines, prostaglandins and leukotrienes responsible for inflammatory and allergic reactions, which explains the use of grape seed extract in the treatment of asthma. Dietary supplements are food products whose purpose is to supplement the normal diet, consisting of concentrated sources of nutrients or other substances that have a nutritional or physiological effect, in simple or combined form, and are marketed in such a way as to allow a specific dosage of each product and to be taken in small unit quantities.