People who follow the ketogenic diet eat a low-carbohydrate, high-fat diet to induce a bodily process called ketosis. There are several signs of ketosis that can indicate whether or not the diet is working. Learn more here.
Orthopnea is a symptom rather than a condition. It is a shortness of breath that only occurs when a person is lying down and usually subsides when they sit or stand up. Causes include conditions that affect the heart or lungs, such as heart failure or chronic obstructive pulmonary disease (COPD). Learn more here.