I cannot help it! i am only 23 and am thin. how dangerous is prehypertension?

Check your BP: First, know your blood pressure. That means having it measured by a health care professional or measuring it yourself with a high-quality home blood pressure machine. Don’t count on headaches, nosebleeds, a red face, or mental stress to warn you that your pressure is too high — none of these traditional signs is reliable. Instead, have your pressure measured with every check-up; once a year.