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Vaccines prevent between 2.5 and 4 million deaths every year.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.
People about to have surgery must tell their health care providers about all supplements they take.
Blood is approximately twice as thick as water because of the cells and other components found in it.
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