Hemorrhoids are the result of distension of the veins surrounding the anus. According to Mayo Clinic, these veins are prone to bulging when they are put under pressure, which is often the result of pregnancy, obesity or behaviors that strain the area. Hemorrhoids are more likely to develop among the elderly because the tissues that restrain the veins loosen with age and lose much of their elasticity.
According to Mayo Clinic, hemorrhoids are commonly caused by carrying extra weight, whether becuase of obesity or pregnancy, or strain on the tissues around the anus. Habitually straining during bowel movements and sitting for extended periods on the toilet are risk factors in developing hemorrhoids, as are chronic constipation and diarrhea.
According to Harvard Medical School, hemorrhoids are rarely, if ever, dangerous, but they can be uncomfortable and painful if left untreated. Hemorrhoids are divided into two types depending on where they form. Internal hemorrhoids develop among deep veins and rarely cause discomfort, but they can cause rectal bleeding with bowel movements. External hemorrhoids can be very painful because their surfaces are exposed to the alimentary canal and are subject to irritation by passing feces. They frequently become inflamed and are prone to clotting.