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There are approximately 3 million unintended pregnancies in the United States each year.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
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.
Asthma cases in Americans are about 75% higher today than they were in 1980.
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
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