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Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.
The human body produces and destroys 15 million blood cells every second.
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