The six most commonly found elements in living things are carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. These elements make up the bulk of organic material; however, only about 25 elements are necessary for life.
Hydrogen is the most abundant element in organic materials as it makes up 59 percent of cells. Oxygen makes up 24 percent, while carbon and nitrogen make up 11 percent and 4 percent, respectively. Together, phosphorus and sulfur account for about 2 percent of elements in cells. Humans are made up mostly of hydrogen, oxygen, carbon and nitrogen as these elements account for 96 percent of the cells in the body.
Other important elements in the body include calcium, potassium, sodium, chlorine, magnesium, iron, fluorine, zinc, copper, iodine, selenium, chromium, manganese, molybdenum and cobalt. The body takes in many of these elements through diet and multivitamins, and each has an important function in the body. Calcium, for instance, strengthens bones, but it also helps with contracting muscles and regulating proteins, while fluorine helps maintain healthy teeth. Sodium assists the body with sending electrical signals. Iron is essential because it carries oxygen in the blood to different parts of the body. Zinc helps to maintain the consistency of genes.