Yes, the process of quitting can be trying, but your body will thank you. According to the American Cancer Society, benefits can begin in just minutes. After 20 minutes, your heart rate and blood pressure drop. Twelve hours after quitting, the amount of carbon monoxide in your blood returns to normal. As time goes on, circulation and lung function improve, and the risk of heart disease goes down. After five years, your risk of smoking-related cancers can be cut in half. Quitting smoking comes with dozens of other health benefits, all of which could extend and improve your life.