The human body is about two-thirds oxygen

Oxygen's influence and its role in Human Body

Oxygen in Human Body
In the human body, the oxygen is absorbed by the blood stream in the lungs, being then transported to the cells where an elaborated change process takes place.

Oxygen plays a vital role in the breathing processes and in the metabolism of the living organisms.

Probably, the only living cells that do not need oxygen are some anaerobic bacteria that obtain energy from other metabolic processes.

The nutrient compounds, inside of the cell, are oxidized through complex enzymatic processes.

This oxidation is the source of energy of most of the animals, mainly of mammals.

The products are carbon dioxide and water (exhaled air has a relative humidity of 100%), which are eliminated by the human body through the lungs.

Click the link below to read more about:

The Physiology of Respiration in human and oxygen transport

Appropriate levels of oxygen are vital to support cell respiration. Oxygen plays an important role in the energy metabolism of living organisms.

The living cell is the site of tremendous biochemical activity called metabolism.

This is the process of chemical and physical change which goes on continually in the human body: build-up of new tissue, replacement of old tissue, conversion of food to energy, disposal of waste materials, reproduction - all the activities that we characterize as "life."

Research shows that cells have only a "limited number" of cell divisions possible in a human lifetime.

Studies show that by the time you're 20 most of the cells that make up your body have used up half of the divisions available in their cell lifespan.

By the time you're 40, there are maybe only 30% of your possible cell divisions left. When the cells use up their natural allotted cell divisions, the end is death!

Cellular respiration

Molecular oxygen, O2, is essential for cellular respiration in all aerobic organisms. Oxygen is used as an electron acceptor in mitochondria to generate chemical energy.

Take a look inside the cell to see these "powerhouses" of the cell,

petite organelles mitochondria, click here.

In the human body, oxygen uptake is carried out by the following processes:

Oxygen diffuses through membranes and into red blood cells after inhalation into the lungs. The heme group (that consists of an iron) of hemoglobin binds oxygen when it is present, changing haemoglobin’s color from bluish red to bright red.

A liter of blood can dissolve 200 cc of oxygen gas, which is much more than water can dissolve.

After being carried in blood to a body tissue in need of oxygen, O2 is handed-off to an enzyme (monooxygenase) that also has an active site with an atom of iron.

The enzyme uses oxygen to catalyze many oxidation reactions in the body (metabolism). Carbon dioxide, a waste product, is released from the cell and into the blood, where it combines with bicarbonate and hemoglobin for transport to the lungs. Blood circulates back to the lungs and the process repeats.

Find out more about cell, click here

A small part of the waste that comes from our body cells is watery, or easily dissolved in water; Furthermore, this is transported in the blood to a specific set of filter organs—the liver and the kidneys—and poured out of the body as the urine.

Another part of waste is passed off through the skin in the form of watery vapor as perspiration, or sweat. But part of the waste can be gotten rid of only by burning, and what we call burning is another name for combining with oxygen, or to use one word—oxidation;

Moreover, this is precisely the purpose of the carrying of oxygen by the little red blood cells from the lungs to the deeper parts of the body—to burn up, or oxidize, these waste materials which would otherwise poison our cells. When they are burnt, or oxidized, they become almost harmless.

While oxygen supports our life, and "oxidizes" or "burns" food to create energy and heat for our bodies, certain types of altered oxygen molecules called "Free Radicals" which are ever-present in our bodies, will damage our own cells and even our DNA, causing degeneration and diseases such as cancer.

A "radical" is an atom with an unbalanced electrical charge, and it will seek to steal electrons from other atoms - such as the atoms of our body cells!

As Dr. Tai likes to say, the oxidation of cells by free radicals makes the human body "rust" like oxidation of metal makes it rust - and you know what rust does to the strength and natural beauty of the metal.

Our bodies need the help of "antioxidants" to neutralize the oxidation properties of those invading free radicals.

There are thousands of research papers that point to the production of free radicals as the primary cause of aging.

Free radicals are unstable molecules in the body created as part of the waste products or normal cellular metabolic activities. YOU ARE ONLY AS OLD AS YOUR CELLS! Recent research has given new hope to the task of rejuvenating and extending the lifespan of cells.

This cellular rejuvenation, life extension, and improved vitality has been achieved using special antioxidants that can actually keep cells looking and acting younger - and may even reverse the aging process !

The human body represents one of the most perfectly designed and coordinated structures. However, all these structures are held in position by a dense network of systems which constantly work together to keep us going.

The brain represents only 2% of the human body weight; it receives 15% of the cardiac output, 20% of total body oxygen consumption, and 25% of total body glucose utilization.

The energy consumption for the brain to simply survive is 0.1 calories per minute, while this value can be as high as 1.5 calories per minute during crossword puzzle-solving.

When neurons in a particular region of the brain are highly active, they consume a great deal of oxygen, which results in recruitment of extra blood flow to that region.

Neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, motor neurone disease, and Huntington's disease are caused by the gradual death of individual neurons, leading to decrements in movement control, memory, and cognition.

Mental performance in the human body can be improved by "feeding" the brain with extra oxygen or glucose, according to research published today that could have implications for the treatment of dementia.

It's well known that after about nine minutes of no oxygen, from drowning or whatever, you can kiss your brain good-bye. Brain cells are extremely sensitive to oxygen deprivation and can begin to die within five minutes after oxygen supply has been cut off.

Decrease of oxygen supply to the brain even though there is adequate blood flow caused by carbon monoxide poisoning, pollution in our cities, choking or suffocation can create conditions like tiredness, depression, irritability, poor judgment and health problems.

Increasing the oxygen supply to the brain and nervous system will reverse these conditions.

The oxygen regimen improves alertness, reflexes, memory and apparently intelligence, and may offer the elderly a new weapon against senility and related disorders. Alzheimer's and Parkinson's are reported to be responding to it. Alcoholics who start taking oxygen supplement soon loose interest in alcohol.

To read more about Brain, click here!

Chemical composition of the human body

The size of the human body is firstly determined by diet and secondly by genes. Body type (slim, fat, tall, petite, wide-shouldered, etc) and body composition (percentages of fat, bone and muscle) are influenced by postnatal factors such as diet and exercise.

By the time the human reaches adult-hood, the body consists of close to 100 trillion cells. Each is part of an organ system designed to perform essential life functions.

By mass, human cells consist of 65-90% water (H2O), and a significant portion is composed of carbon-containing organic molecules. Oxygen therefore contributes a majority of a human body's mass, followed by carbon.

99% of the mass of the human body is made up of the six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.

In order to understand the relation of food to the sustenance and repairing of the body, it will be necessary to learn, first, of what the human body is composed, and the corresponding elements contained in the food required to build and keep the body in a healthy condition.

The following table gives the approximate analysis of a man weighing 148 pounds:

ElementPercent by mass
Oxygen (O)65
Carbon (C)18
Hydrogen (H)10
Nitrogen (N)3
Calcium (Ca)1.5
Phosphorus (P)1.2
Potassium (K)0.2
Sulfur (S)0.2
Chlorine (Cl)0.2
Sodium (Na)0.1
Magnesium (Mg)0.05
Iron (Fe), Cobalt (Co), Zinc (Zn), Iodine (I)<0.05 each
Selenium (Se), Fluorine (F)<0.05 each

As food contains all these elements, and as there is constant wearing and repair going on in the body, it will be readily seen how necessary some knowledge of the relation of food to the body is, in order to preserve health.

Oxygen is found in almost all biomolecules that are important to (or generated by) life. Only a few common complex biomolecules, such as squalene and the carotenes, contain no oxygen. Of the organic compounds with biological relevance, carbohydrates contain the largest proportion by mass of oxygen.

All fats, fatty acids, amino acids, and proteins contain oxygen (due to the presence of carbonyl groups in these acids and their ester residues).

Read further here about: periodic table of the chemical elements and dietary minerals in the human body.

"The molecules of hydrogen, oxygen, carbon, nitrogen, iron, phosphorus, calcium, and so on, in a living body, are themselves no more alive than the same molecules in inorganic matter.

Nearly nine tenths of a living body is water;

Is not this water the same as the water we get at the spring or the brook? Is it any more alive? Does water undergo any chemical change in the body? Is it anything more than a solvent, than a current that carries the other elements to all parts of the body?

There is any number of chemical changes or reactions in a living body, but are the atoms and molecules that are involved in such changes radically changed? Can oxygen be anything but oxygen, or carbon anything but carbon? Is what we call life the result of their various new combinations?

Chemistry is all-potent. A mechanical mixture of two or more elements is a simple affair, but a chemical mixture introduces an element of magic.

Free or single atoms are very rare; they all quickly find their mates or partners. This eagerness of the elements to combine is one of the mysteries.

A living thing is more than a machine, more than a chemical laboratory.

Life comes to matter as the flowers come in the spring, — when the time is ripe for it, — and it disappears when the time is over-ripe.

Man appears in due course and has his little day upon the earth, but that day must as surely come to an end. Yet can we conceive of the end of the physical order? The end of gravity? Or of cohesion?

The air may disappear, the water may disappear, combustion may cease; but oxygen, hydrogen, nitrogen, and carbon will continue somewhere.

There is no life without chemistry, but there is chemistry without life."

Fragments from the book: The Breath of Life by John Burroughs

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