An adult human body contains around 37 trillion human cells and 200 different cell types.

Human beings are complex multicellular organisms made up of trillions of cells. Scientists estimate that the adult human body contains around 37 trillion human cells and 200 different cell types. The human microbiota (a collection of microorganisms found primarily in the gut) consists of a further 10-100 trillion microbial cells.

To reach this number, scientists painstakingly combed the existing scientific literature for details on the numbers and types of cells found in individual body structures. By estimating the total number of each type of cell in the human body and adding them all together, they eventually concluded that the human body contains approximately 37.2 trillion cells.

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