Oxygen

Oxygen is essential for life. As the most abundant element of the Earth's crust, oxygen compounds form a major part of oceans, rocks, and all other living things. In fact, over 62 percent of the Earth's crust (by mass) is made up of oxygen. It also constitutes 65 percent of the elements of our body, including blood, organs, tissues, and skin.

Oxygen is a clear, odorless gas that can easily be dissolved in water. Each molecule of oxygen (a molecule being the smallest amount of a chemical substance that can exist by itself without changing or breaking apart) is composed of two atoms of oxygen and is known by the chemical formula O2.

Oxygen is involved with all body functions, and we require a continual supply of oxygen to survive. The average person needs some 200 milliliters (about 1 cup) of oxygen per minute while resting and nearly 8 liters (approximately 2 gallons) during periods of strenuous activity. The brain-which makes up about 2 percent of our total body mass-requires over 20 percent of the body's oxygen needs. While we can go without food for several months and survive without water for a couple of days, we cannot live without oxygen for more than a few minutes.

Oxygen makes up 21 percent of the air we normally breathe. Smokers or people who live in heavily polluted environments are likely to consume less. The oxygen we breathe reacts with sugars (from the food we eat and from the breakdown of fats and starch in the body) to produce carbon dioxide, water, and energy. The energy from this process, a form of combustion, is stored in a compound called adenosine triphosphate (ATP). ATP is essentially the fuel we use to live, think, and move.

The lungs, heart, and circulatory system deliver sufficient amounts of oxygen to the entire body. This oxygen creates the energy we need to survive and thrive. At the same time, the lungs take the waste product carbon dioxide (CO2) from the blood and discharge it back into the air. It is estimated that we breathe in 2500 gallons of air each day. In contrast, trees take in carbon dioxide and, through the process of photosynthesis, convert carbon dioxide into oxygen and send it back into the atmosphere for us to enjoy once more.

When we are in a closed room full of people, we feel tired and sluggish. Even though this room is filled with air, that air is deficient in oxygen and high in carbon dioxide. A number of studies have linked the high CO2 level in the cabins of commercial jet aircraft to a variety of temporary health problems, which include exhaustion, headaches, and nose, eye, and throat discomfort. Symptoms often disappear within a couple of hours, when passengers leave the aircraft and oxygen consumption returns to normal.

How Do Humans Become Oxygen Deficient?

Polluted Air
Perhaps the most important factor in oxygen deficiency is air pollution. For those who smoke or are unfortunate enough to breathe in secondhand smoke, the oxygen content of the air is even lower. Automobile exhaust, factory emissions, and burning garbage are the three greatest causes of lowered oxygen content in the air we breathe.

Devitalized Foods
Fresh fruits and vegetables contain an abundance of oxygen that is dissolved in water. When we eat generous amounts of fresh, raw vegetables and fruits, our intake of oxygen is increased along with the valuable vitamins and minerals these foods contain.
Foods that have been heavily processed, cooked, and preserved through canning tend to be very low in oxygen. High-fat foods like meat, eggs, and dairy products tend to be lower in oxygen as well. The standard American diet tends to be very low in oxygen content. It should be no surprise that that type of diet has been linked to a wide variety of degenerative diseases like atherosclerosis, cancer, and diabetes.

Poor Breathing
Healthy breathing involves deep, rhythmic breaths that fill the lungs with air and then exhale that air fully back into the atmosphere. Because of pollution, stress, or simply habit, most people do not breathe fully. For example, many of us were taught to breathe by relying on the muscles of the upper chest only, which tends to ventilate the upper part of the lungs only. By utilizing the diaphragm as well as the upper chest in breathing, we are able to take fuller breaths and utilize more of the available oxygen in the lungs.