A new study has estimated that the human body contains an impressive number of cells. Researchers analyzed over 1,500 scientific papers to determine that an average adult has around 36 billion cells, while adult women have 28 billion and 10-year-old children have approximately 17 billion. The study, published in the journal PNAS, considered the size and number of 400 types of cells in 60 tissues of the body.

The research revealed a consistent inverse relationship between the size and number of cells. In other words, larger cells have a smaller total number compared to smaller cells. This pattern spans a wide range of cell sizes, from tiny red blood cells to large muscle cells.

The study authors acknowledged limitations in their findings. The figures provided are based on “average” adults and children and do not take into account significant variation in size and weight among individuals. The researchers also noted that there is uncertainty in their estimates due to reliance on indirect measurements rather than direct measurements of cell mass.

However, the study has highlighted discrepancies in previous cell count estimates, which could have implications for our understanding of lymphocyte-related health and diseases like HIV and leukemia. The study found that there are approximately 2 trillion lymphocytes in the human body, four times more than previous estimates.

Further research is needed to gain a more comprehensive understanding of cell counts in the human body, especially in relation to women and children. However, this study provides valuable information about the large number of cells that make up the human body and the relationship between size and cell count.

– New Scientist: “Human body estimated to carry around 30 trillion human cells”
– PNAS: “Scalable generative models for accurate labeling and tracking of dynamic subcellular structures in fluorescence microscopy”