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Atoms & Life

There are 92 elements that occur naturally on Earth. For living things, only 11 of these elements are found in larger than trace quantities. In other words, any amount 0.01 or less is considered a trance element. For vertebrates, such as humans, there are two additional elements that occur in larger than trace amounts these are Iodine and Iron.

Periodic Table Illustration

Of the elements found in the human body, four of them make up the largest percentage of our body weight (96.5%). The four elements are oxygen, hydrogen, carbon, nitrogen.

Elements in Human Body by Percent

Four common elements in human body

The elements - Oxygen, Carbon, Hydrogen and Nitrogen account for 96.5% of your body weight.

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