Chemical Elements in the Human Body


“And in yourselves. Then will you not see?”       —Surat Al-dhariyat (verse 21).

Our bodies surprise us with their secrets, which are continuously being revealed as more scientific research is conducted. This confirms that no matter how knowledgeable we become, there is yet much more to discover. In the past, it was difficult to convince people that their bodies contain chemical elements from the Periodic Table, including valuable ones, such as gold and copper. However, now that several studies have confirmed that these elements do exist in our bodies, the mission has become much easier.

Almost 99% of the human body mass consists of six main elements; namely: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphor; 65–90% of each cell in the body is composed of water, as such, oxygen and hydrogen are among the main constituents of the human body.

1. Oxygen

Chemical symbol O2; 65% of the human body weight.

In general, all living organisms depend on oxygen for survival. Oxygen is vital for breathing; it makes 20% of the air that we inhale. The human brain needs oxygen to perform its biological functions; if oxygen did not reach the brain, the body would die in a few minutes. Oxygen exists in our bodies mainly in the form of water; it represents 89% of the water weight.

2. Carbon

Chemical symbol C; 18% of the human body weight.

Carbon is a quadrivalent element; that is, it can bond with four chemical elements, which makes it a fundamental atom in organic chemistry. Carbon chains are used to build carbohydrates, fats, and proteins; breaking these chains provides the human body with energy.

3. Hydrogen

Chemical symbol H2; 10% of the human body weight.

Hydrogen is a main constituent of the DNA; as such, it exists in every molecule in all living cells. The amount of hydrogen present in the DNA is affected by the amount of water in the human body. The human body needs two-and-a-half liters of water daily, or according to its weight, to keep the DNA healthy and avoid diseases.

4. Nitrogen

Chemical symbol N2; 3% of the human body weight.

Nitrogen is the most important constituent of animal cells' protoplasm, as well as the amino acids that form proteins, and the acids that form the DNA.

5. Calcium

Chemical symbol Ca; 1.5% of the human body weight.

Calcium is an essential element in the human body, mostly concentrated in teeth and bones; calcium regulates protein and muscle contractions. It also preserves bones density and strength, and regulates heartbeats and blood clotting.

6. Phosphorus

Chemical Symbol P; 1% of the human body weight.

Phosphorus is found in the human body in the form of phosphates, a phosphorus atom associated with four atoms of oxygen. The human skeleton and brain are reservoirs of phosphates, where it is found in the form of calcium phosphate. Phosphates are also present in the form of the Adenosine triphosphate (ATP) energy molecule, which releases 7.3 Kcal/mol of energy to perform different biological functions.

7. Potassium

Chemical symbol K; 0.35% of the human body weight.

Red blood cells contain most of the potassium found in the body, followed by muscles, and then brain tissue. Potassium transfers nerve signals, regulates heartbeat, and reduces blood sugar. It also maintains bone health, increases its density, and prevents its fragility through maintaining the balance of acids that store calcium inside the body.

8. Sulfur

Chemical symbol S; 0.25% of the human body weight.

Sulfur plays a role in providing proteins the shape they need to perform their functions.

9. Sodium

Chemical symbol Na; 0.15% of the human body weight.

Sodium functions similar to potassium in transmitting nerve signals between the cells; it also contributes to regulating water amounts in the body.

10. Gold

Chemical symbol Au; 0.2 mg of the human body weight.

Gold is found in the blood; it plays a crucial role in protecting the body and preserving joints. It is also an essential element in transmitting electric signals throughout the body.


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