Vitamin A is not a single compound, but a series of derivatives of retinol, including retinol, retinaldehyde, retinoic acid, retinyl acetate, retinyl β -palmitate and so on.
Vitamin A exists only in animals and is rich in fish, especially cod liver oil. Plants do not contain vitamin A, but many vegetables and fruits contain provitamin-carotene, which can be decomposed into vitamin A in the small intestine. Among them, 1 molecule of β -carotene can be decomposed into 2 molecules of vitamin A, while 1 molecule of α -carotene or γ -carotene can only produce 1 molecule of vitamin A. ..
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The role of vitamin a
1, prevent night blindness and vision loss, and help to treat various eye diseases (vitamin A can promote the formation of ocular photosensitive pigments);
2. It has the function of resisting respiratory infection;
3. Help the immune system to function normally;
4. You can recover as soon as possible if you are sick;
5, can maintain the health of the tissue or organ surface;
6, help to get rid of age spots.
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