There are a number of possible explanations. Bruises occur when a small vessel near the skin's surface leaks blood into the surrounding tissue after a trauma. Regularly taking certain medications, such as ibuprofen or aspirin, that thin the blood and make it less likely to clot, can make you more susceptible (even after a minor injury). When you get a bump, apply a cold compress for 15 to 20 minutes and elevate the area to minimize the mark. If, however, this tendency to bruise is new, and the marks seem to be appearing for no reason, see a doctor. It's possible you have anemia or that you're not getting enough folic acid or vitamins C or K. Also consult your M.D. if your bruises become abnormally large or painful. Occasionally, bruises can be a sign of a blood disorder or liver problem that needs to be treated.
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