Vitamin A

Vitamin A

Vitamin A is the name of a group of fat-soluble retinoids, including retinol, retinal, and retinyl esters. Vitamin A is involved in immune function, vision, reproduction, and cellular communication. Vitamin A is critical for vision as an essential component of rhodopsin, a protein that absorbs light in the retinal receptors, and because it supports the normal differentiation and functioning of the conjunctival membranes and cornea. Vitamin A also supports cell growth and differentiation, playing a critical role in the normal formation and maintenance of the heart, lungs, kidneys, and other organs.

Benefits of Vitamin A

 Immune Function

Many different functions within the immune system are dependent on an individual obtaining sufficient levels of vitamin A, meaning it helps to promote a healthy immune response. The genes which are involved in the immune response are regulated and controlled by vitamin A, meaning it is essential for fighting off viruses such as cold and flu.

 Eye Health

The old wives tale of ‘eating carrots to make you see in the dark’ does have some truth to it. Granted, eating carrots isn’t going to give you night vision, but the beta carotene which is found in them, among other plants, plays a role in preventing macular degeneration in the eyes which is a factor in blindness and vision loss.

Improved Skin

Studies have shown that vitamin A can fight acne and improve your overall skin health. It helps by contributing t preventing the development lines and wrinkles through producing more collagen. 

Cell Growth

Vitamin A is essential for effective healing as well as re-growth of skin.

It is required to support internal and external skin cells. The vitamin itself is required in order to form glycoproteins which help bind the tissues together.

Inflammation

Vitamin A also boasts antioxidant properties which allow it to neutralise free radicals within the body. These would normally cause damage to tissue and surrounding cells.

For example: vitamin A can lower the risk and severity of some food allergies since it prevents your body from overreacting. 

There are many symptoms of Vitamin A deficiency through which one can detect low levels of Vitamin A in the body. These symptoms are as follows

a)      Reduced vision in the night or dim light; which means that they will not be able to distinguish outlines of images in reduced illumination. They might however still go on to see normally during day light hours until the night blindness turns into some other severe form.

b)      Dry eyes which could also lead to xeropthalmia; this is a severe form of night blindness in which the outer membrane of the eye, known as conjunctiva loses its goblet cells. These cells perform to release mucus in the eye, to keep it lubricated. The loss of goblet cells results in this condition – xeropthalmia in which the eye can no longer produce tears. These dead or lost cells can even accumulate on the outer layer of the eye resembling a form of debris. This debris can easily lead to blindness or any other infection.

c)      Eye inflammation can also result from Vitamin A deficiency. Because of the inflammation, the eyelids and surrounding tissues along with eyes can get affected. This may include corneal inflammation as well.

d)      The child or adult may experience susceptibility towards respiratory infection and urinary infections.

e)      Growth can be halted in children due to vitamin A deficiency.

f)       Skin might also show signs of Vitamin A deficiency. For example it may get rough and/or dry.

Vitamin A Sources:

  Egg yolk

  Dark-colored fruit

  Dark leafy vegetables

  Liver, beef, and fish

  Fortified milk and dairy products (cheese, yogurt, butter, and cream)

Recommended Dietary Allowances (RDAs) for Vitamin A
Age	Male	Female	Pregnancy	Lactation
0–6 months*	400 mcg RAE	400 mcg RAE
7–12 months*	500 mcg RAE	500 mcg RAE
1–3 years	300 mcg RAE	300 mcg RAE
4–8 years	400 mcg RAE	400 mcg RAE
9–13 years	600 mcg RAE	600 mcg RAE
14–18 years	900 mcg RAE	700 mcg RAE	750 mcg RAE	1,200 mcg RAE
19–50 years	900 mcg RAE	700 mcg RAE	770 mcg RAE	1,300 mcg RAE
51+ years	900 mcg RAE	700 mcg RAE

* Adequate Intake (AI), equivalent to the mean intake of vitamin A in healthy, breastfed infants.

 

Vitamin A food

Posted in: Fat Soluble Vitamins