Vitamin A is one of the essential vitamins, one of those that the body cannot do without.
It is vital for proper cell function, and on this page we will be looking at precisely how the body uses it, its sources both in plants and animals and how a lack of it manifests.
Vitamin A is an oil-soluble vitamin that is necessary for the repair of the body’s tissues.
It is essential in maintaining a healthy immune system - it helps to fight off infections.
There are a number of other known benefits of Vitamin A, and they are mainly derived from compounds within it such as retinoids.
Before we get to its sources, let’s first look at which bodily functions need vitamin A for optimum function, and what will happen if you don’t get enough of it.
We have already mentioned that it’s used to build a healthy immune system. It does this by building a healthy mucus membrane so that pathogens cannot penetrate easily. The mucous membrane acts as a barrier or a shield.
The epithelium is the membrane that covers internal organs. In the same way that vitamin A builds a mucous membrane that wards off disease, it helps to build a healthy epithelium so that your organs are in much healthier sacs.
It is vital for the eyes as it’s the one which helps them to adjust when you move from a lighter to a darker place or vice versa. When you are not able to make this adjustment properly, that’s known as night blindness.
Your skin is healthy largely because of vitamin A. It treats pimples and cures conditions like eczema.
If you look at many anti-ageing creams, you will notice that they contain vitamin A and E. The vitamin A contains antioxidant, neutralizing free radicals that prevent formation of wrinkles and therefore reverse the symptoms of aging. These free radicals are also used internally to prevent degenerative changes that are caused by arthritis.
It is known to prevent certain cancers, like cancer in the glands and epithelial tissues (breasts, skin, and other passages in the body). Most body organs are lined by epithelial tissues, but not enough research has gone in to show just to what extent vitamin A will help with cancers that affect these organs.
It is known to build resistance against respiratory tract infections.
It is necessary for the storage of fats and the synthesis of glycogen and protein.
It is also important in the repair of broken cells because it gives them an optimum environment for healing. This is through the mucous membrane lining that it provides that keep pathogens at bay.
It is believed to be essential for good eyesight.
What happens if you do not get enough vitamin A?
There are several things that will indicate a deficiency, but the one that should be of greatest concern is compromised immunity.
A compromised immune system is an opens the door to any disease.
If you’re not taking in enough vitamin A, the mucous membranes that would protect you have no ability to do so.
Without immunity, you may eat healthy, but contact with pathogens of any kind may leave you feeling ill.
The only problem here is that because one is open to so many conditions of all kinds, its hard to trace their cause back to a lack of vitamin A.
That’s what makes it dangerous, and eventually the symptoms may have to get worse and manifest in diseases that are directly related to a deficiency of vitamin A for a diagnosis.
There are also other side effects that come from a deficiency of vitamin A:
The most commonly reported, and maybe because it’s directly traceable to vitamin A is night blindness. This will happen because the membranes which water your eye and enable it to adjust to the dark are dry and so the eyes cannot adjust as needed to see in the dark.
In the same way as in the above point, one will have itchy, sore eyes, and these are as a result of dry membranes. In some cases, especially in children when the deficiency is very severe, it can result in corneal blindness.
The respiratory tract is left open to infection, as a result of which one will experience many more respiratory tract infections.
The skin is coarse and dry, and it starts to wrinkle prematurely. This is a direct indicator of deficiency.
The scalp becomes dry, flaky and the hair dull. Because hair needs some conditions to thrive, like a healthy scalp, there may be eventual hair loss or thinning of hair.
There will be insomnia and poor appetite, all linked to the other general health issues that you might be having.
Sources of Vitamin A
You can find it in plentiful quantities in fish liver oils, egg yolks and butter.
It may be added to some margarines, but the best way to ensure that you get it is to take butter instead.
Liver, beef, yogurt and cheese will also contain vitamin A.
Yellow and orange fruits will also contain carotene, a component of vitamin A.
Carrots, tomatoes, broccoli, oranges, peaches and oatmeal are good plant sources.
Recommended Daily Allowance
In the US, the recommended RDA is that you take at least 1500 IU for infants, 3000 for children and 6000 for adults.
If you are taking it on a supplementary course, 10,000 IU is recommended. Prescription strength is 25,000 to 100,000 IU.
Stick to the recommended dosage as taking too much Vitamin A can have side effects.
The only way to prevent diseases that are caused by lack of vitamin A is to make sure that you take it all the time in your diet.
Remember that it’s an essential vitamin and that means that it’s easy to suffer a deficiency if you don’t get enough of it.
In most cases, after diagnosis, the doctor will put you on a course as well as a diet that will boost your body's vitamin A reserves.