Cholesterol is a fatty, wax-like substance that exists in every cell of the human body. It plays a crucial role in creating hormones and other essential substances. However, when cholesterol levels in the blood become too high, it can increase the chance of heart problems and strokes. High cholesterol usually doesn’t present any symptoms, so the only way to detect it is through a blood test. In the United States, about one in six adults has elevated cholesterol levels. What the Science Says In