Oxygen is vital to human existence, yet many of us simply don’t get enough. The very act of breathing transports air via the alveoli in the lungs and into the bloodstream where it’s transported to cells, tissues, and organs throughout the body. Oxygen is essential for converting nutrients into usable energy for brain and muscle function and so much more. If your doctor finds that you lack adequate oxygen in your blood, he or she may prescribe short or long term oxygen therapy to boost oxygen levels in the blood. For instance, oxygen concentrator volume may be increased in the morning, throughout the day, or overnight while sleeping using a portable oxygen concentrator unit, which supplies a concentrated oxygen via a oxygen-rich gas stream. When oxygen levels in the blood are lacking, hypoxemia occurs, often due to an underlying health issue (i.e., COPD), and the body can experience a domino effect of negative side effects to signal low oxygen. Here are 6 signs your body is lacking oxygen: 1. Headache and mental fog Lack of oxygen often causes a lack of oxygen in the blood, particularly when headaches are chronic and unexplained. In addition to pounding headaches, low oxygen often leads to dizziness, confusion, and loss of memory and focus.