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The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
There are approximately 3 million unintended pregnancies in the United States each year.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
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