Have you ever wondered what a bruise actually is? It’s a pool of blood that has escaped from its blood vessels following an injury to one of the tiny capilliaries close to the surface of the skin caused by a bump, thump, bang or fall at that site. This blood becomes trapped under the skin, causing the familiar discolouration of a bruise, which disappears as the body reabsorbs the leaking blood. Any new bruise will feel tender, and may be swollen too. The reason bruises sometimes look brown or yellow as they heal, is that as the fluids are reabsorbed, a little residual iron from the blood may be left over.