An evergreen shrub commonly found in America, Wintergreen contains Methyl Salicylate, a natural form of Aspirin. The substance diffuses topically into the tissues and in the capillaries and is therefore used as a folk remedy for inflammation and poor circulation, although the concentration in this product has been kept at cosmetic level. Asthmatic people may be sensitive to Wintergreen, which is also common as a fragrance in products such as toothpaste and chewing-gums.