Bruising , a reddish or purple discoloration under the skin, most often results from trauma to the small blood vessels, called capillaries, but can also occur spontaneously. How and Why Bruises Occur Blood leaks out of the capillaries and accumulates under the skin, gradually absorbing over several days. Bruising most often occurs because people run into objects or experience other trauma. Most bruising is easily explained, but frequent bruising that occurs without obvious cause needs prompt investigation, since several serious diseases can cause bruising. In general, women bruise more easily than men. How Aging Increases the Risk of Easy Bruising Bruising increases as people age for several reasons. Skin thins as people age and the capillaries become more fragile. The layer of fat that cushions blood vessels and protects them from injury becomes thinner as well. Older people often take medications and supplements that thin the blood and contribute to easy bruising. Visi
