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Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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