Your body makes about 2 million red blood cells every second
Bone marrow produces them continuously because each red cell lives only around 120 days. The total in your body is roughly 25 trillion.
Bone marrow produces them continuously because each red cell lives only around 120 days. The total in your body is roughly 25 trillion.
Stomach acid is strong enough to dissolve metal, so the cells lining the stomach are replaced roughly every three to four days before the acid can damage them.
Read the fact →A 2014 study estimated humans can distinguish at least one trillion different odours — far more than the old 10,000 figure that textbooks repeated for decades.
Read the fact →The cartilage discs between your vertebrae compress under your weight during the day and expand again while you sleep lying down.
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