Vitamin A: efficacy, food sources and health care products
Vitamin A is fat soluble retinoid , which is stable to heat, acid and alkali but liable to oxidization. There are two types of vitamin A. The first type named retinol, which is the original form of vitamin A and only comes from animal food. The other type is carotene, which can be ingested from both plant-based food or animal-based food. The conversion efficiency from carotene to retinol varies by person. Vitamin A contains photosensitive substances that help make the retina (i.e. rhodopsin), which is very important for night vision. Vitamin A is also essential for body growth and development and maintaining the skin and mucosa, so that the immune system operates normally.