In living things, especially in humans, there are about 11 elements that exist in large quantities. They include oxygen, carbon, hydrogen, nitrogen, calcium, phosphorus, potassium, sodium, chlorine, magnesium, and sulfur. Out of these eleven, the first four elements of this classification constitute about (96.2%) of our body weight.
However, the least abundant element of this classification is sulfur. The percentage of sulfur in our body is measured to be 0.04, whereas oxygen which is the most abundant element in the body constitutes about 65 percent of the total body weight. There is another classification of some elements in the body; they are known as trace elements.
Any element in the body that constitutes less than 0.01 percent of the total body weight is known as a trace element. The majority of all the elements in the periodic table belong to this category. Examples of trace elements are iron, chromium, cobalt, silicon, manganese, zinc, and many others.