Typically veins are generally wider than arteries, and therefore the pressure is lower. Capillaries are tiny vessels, so repsent high resistance to the incoming blood, so the rate of blood flow through will be quite low. All blood from the artery eventually passes through capillaries and into the vein.
Graves' disease. Graves' disease is the most common cause of overactive thyroid. It can run in families and can occur at any age, although it is most common in women aged 20-40 years old. You are more likely to develop Graves' disease if you smoke. Graves' disease is an autoimmune condition.
Gravesâ disease is genetic and tends to run in families â however, stress, smoking, and certain medications and viruses may set it off. Other causes of overactive thyroid include the development of thyroid nodules, inflammation of the thyroid following a virus or during pregnancy, and excessive iodine intake. Key sources of iodine in the diet are seafood, milk, bread and salt.