What are the three most common atoms in your body?

The three most common atoms in our body are Oxygen, carbon and hydrogen. Together these constitute almost 93% of our body, with individual contribution being 65% oxygen, 18.5% carbon and 9.5% hydrogen. Our body is mostly made up of water, which is made up of hydrogen and oxygen (in a 2:1 atomic ratio, that is 2 atoms of hydrogen are combined with 1 atom of oxygen). We are organic life forms, that is, our body parts are made up of carbon compounds. The food that we eat and the sugar molecules that we need to break down to generate energy are all carbon-based molecules. The other macromolecules, such as, lipids and proteins are also carbon-based molecules. Thus, our body is mostly composed of carbon, oxygen and hydrogen.

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