The human body consists of as many as 60 chemical elements. Only 25 of these elements are considered essential to a normal human body. While 21 are considered either trace elements or major elements and are important for health, just four elements make up 96 percent of a body’s mass.
No. 1: Oxygen
Oxygen makes up 65 percent of the human body. Oxygen is the only element inside the human body in its pure form. It aids the body in countless ways, from taking in the very breath of life to helping blood travel through the body to assist in regenerating cells. You can find oxygen throughout the body in water. Water comprises approximately 60 percent of the body's weight.
The Sidekick, Hydrogen
Hydrogen is the chemical partner that joins oxygen to create water. Hydrogen makes up 10 percent of the human body. As the very first element on the periodic table, hydrogen is assigned the number one to represent the single proton in its nucleus. In the human body, as in nature, hydrogen combines with oxygen to become water, which is essential to all life on Earth.
Carbon makes up 18 percent of the human body. Carbon is so essential to life on Earth that living things are appropriately described sometimes as carbon-based life forms. Carbon, oxygen, hydrogen and nitrogen are present in all molecules. It is carbon, however, that helps the molecules grow in the body. Carbon produces the energy humans rely on to live.
Nitrogen for DNA
Nitrogen is only responsible for 3 percent of the human body, but that is twice as much as the next most abundant element. Even though nitrogen is not included in essential molecules such as water and glucose, it is included in the nucleic acids that make up DNA as well as in the amino acids that make up proteins. Nitrogen enters the body when humans consume it in their food.