Vitamin A

Vitamin A or beta-carotene ( Retinol , Akseroftoli) is an essential vitamin that digest fat found in foods of plant and animal origin. This vitamin has a structure and you terpeni belongs but is also terpene alcohol . Full retinol formula is C ₂₀ H ₃₀ O. The substance is a strong yellow color. Retinol is a monovalent primary alcohol, as a hydroxide group is connected to an atom of carbon , which in turn is connected also with only one carbon atom.

Properties 

Vitamin A is the melting point between 62 ° and 64 ° C and boiling point between 137 ° and 138 ° C. Molecular mass is 286.46 g / m.

Sources of vitamin A 

In plants found in the form of beta-carotene, which the body still turns into vitamin A. For this reason, beta-carotene is also called provitamin A. Since beta-carotene only when necessary turns into vitamin A and unlike this is not toxic in large doses, it should be given priority in the event of additional nutritional substance use. Retinol products found in milk , the yolk of the egg and the liver oil of fish.

Vitamin A is necessary for some processes in the human body so it is necessary for the development and construction of the surface and the interior of the skin, immune functioning, etc. for viewing in darkness.

The approximate daily amount required for the body of a man for men is 1 mg retinol (vitamin A around 3350 IE), for women is less 0,8mg retinol (vitamin A IE sometime in 2650). During pregnancy it is best to increase the amount to 1.1 retinol (vitamin A around 3650 IE), breastfeeding 1.5 retinol (about 5025 IE vitamin A).

Signs of vitamin A deficiency are lack of appetite, dry skin, dark appearance and weakened in children presents developing disorders.

Signs of excess vitamin A are headache, lethargy, lack of appetite, the return of food, fall of hair, dry skin and visual disorders (appearance of double images)

Pregnant women should never do to exaggerate the amount of vitamin A. They were recommended to receive 3 mg retinol (vitamin A 10,000 IE) per day so as to ensure the normal physical development of the child.