An international team of researchers has finally – and successfully – estimated the number of cells that make up the human body and that they follow a mathematical pattern that appears in nature.
“The key was looking for papers that described the number of cells in different tissues,” co-author Eric Galbraith, an ecologist at McGill University in Canada. “And then knowing that those kinds of tissue were made up of particular cells and knowing what the size range of those cells were.”
Data from 1,500 published sources determined that men have roughly 36 trillion cells, women have some 28 trillion, and 10-year-olds have about 17 trillion. The newly published study reveals that if a human’s cells of similar sizes are grouped, each group contributes about the same amount of mass to the body. Indeed, human cell size varies widely. The cell mass, size range, and count for 1,200 cell groups have been estimated. These can be further broken down into 400 cell types across 60 tissues. Smaller cells, such as blood cells, are more common than larger ones, like muscle cells.