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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
You should not take more than 1,000 mg of vitamin E per day. Doses above this amount increase the risk of bleeding problems that can lead to a stroke.
The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
In 1864, the first barbiturate (barbituric acid) was synthesized.
![People have seen patterns in the stars since ancient times.[5] This 1690 depiction of the constellat](https://biology-forums.com/gallery/47/medium_12359_26_01_13_3_44_40.png)

