Microscope Science :: Microscopes For Sale

How many cells do you have?

How many cells in the human body


Estimating the number of your body's building blocksis not as straightforward as it seems

microscope science human cellsThe number of cells you have depends on your gender, size and age.

By the most recent estimates, the average human is made up of approximately 37.2 trillion cells. To put that unthinkably large number into some perspective, consider that there are 'only' 100 billion stars in the entire galaxy.

Even if it were feasible to painstakingly isolate every single cell, simply counting to 37.2 trillion would take you over a million years. So how exactly did scientists reach this mind-boggling number?

A team of researchersfrom Italy, Greece and Spain used a systematic approach: they considered different cell types individually.

They gathered as much information as possible from scientific research papers to find the total number of cells in the various organs and systems of an average person, and added up these results to get the titanic total of 37.2 trillion.

Counting the number of cells in a human being may seem like a pointless exercise, but this information is valuable for a range of applications.

For example, accurate cell counts can improve the precision of computer models of the body. This could help scientists to virtually map diseases and try out potential treatments.

Comparing a patient's cell count of a particular organ to that of the average human may also help doctors to diagnose diseases.

Counting cells

See how your cell types stack up?

  • Small and mighty Red blood cells: 5.5% total mass Despite their vast numbers, each red blood cell only weighs around 25-35 billionths of a gram, so they make up very little of your mass.

  • Density

    Muscle: 44% total mass
    Fat: 28.5 % tota mass

    Most of your body weight is muscle cells (shown in purple) and fat cells (shown in yellow). While there are comparatively few of them, they ar e relatively large.

  • Red blood cells

    70.7% total cells
    se tiny cells coursing through your arteries and veins, transporting oxygen around your body.

  • Nervous system

    8.3% total cells
    You have roughly 100 billion neurons, insulated and supported by 3 trillion glial glands.

  • Blood and lymph vessels

    6.8% total cells
    Approximately 2.5 trillion endothelial cells line your y's vast network of veins, arteries and lymphatic vessels.

  • Skin cells

    5.5% total cells
    Your skin is your largest organ, composed of around 2 trillion cells.

And the rest

8.7% total cells
Although they make up the majority of your mass, you only have around 50 billion fat cells and 17 billion muscle cells.