The human brain has the capacity to store everything that you experience.
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After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
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It takes about 20 seconds for a red blood cell to circle the whole body.
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It takes twice as long to lose new muscle if you stop working out than it did to gain it.
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For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
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An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
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The largest cell in the human body is the female egg and the smallest is the male sperm.
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