Every vitamin is important for the body! That is why we are dedicating a section to vitamin A, a fat-soluble nutrient that helps us form and keep many organs and systems healthy.
Traditionally associated with carrots and visual acuity, this vitamin goes far beyond maintaining healthy eyes. This is because it participates in the creation, growth, and even health of our cells. Can you believe this incredible potential? Keep reading our article to learn more about it.
- 1 Key Facts
- 2 The 4 Functions of Vitamin A That You May Not Know
- 3 How Can You Make the Most of the Properties of Vitamin A?
- 4 Our Conclusions
- Vitamin A is a nutrient necessary to maintain the health of many body organs and systems, such as the skin and immune cells (our defences).
- You can obtain vitamin A from a balanced diet and food supplements. However, excessive intake of vitamin A can be toxic.
- Beta-carotene (provitamin A) is a safer form of this nutrient. However, you could sometimes be prescribed supplements containing preformed vitamin A. Follow your doctor’s recommendations to avoid making mistakes!
The 4 Functions of Vitamin A That You May Not Know
Vitamin A is one of the four vitamins (A, D, E, K) that cannot be excreted in the urine. This means that it remains in the body for much longer after we consume it through food (1).
Vitamin A is stored in the liver until it is needed somewhere in our body, where it can fulfil the following functions (2):
|Organs and systems||Effects|
|Eyes||Improved visual acuity|
|Heart||Prevention of heart disease|
|Neurons||Prevention of neuron degeneration|
|Immune system||Production of immune cells|
Prevention of autoimmune diseases
|Reproductive system||Improved fertility|
Support of babies’ health
|Others||Prevention of diabetes and certain types of cancer|
1. It improves visual acuity
One of the most widely known effects of vitamin A is its ability to preserve visual acuity, and more specifically night vision (3).
It does so because vitamin A is a precursor (like a fundamental ingredient) for the production of rod cells in our retina. These cells are responsible for capturing light, which means that we can suffer from night blindness if we don’t have them (4).
In addition, vitamin A appears to be involved in the prevention of age-related macular degeneration (5). High levels of certain types of vitamin A (carotenoids) such as beta-carotene and alpha-carotene reduce the risk of this disease by up to 25% (6).
2. It is a powerful antioxidant
Oxidation is a normal and necessary process for our survival. However, it can produce an excess of free radicals which leads to the premature ageing of our cells and the development of certain diseases.
Carotenoids derived from vitamin A fight these free radicals (7), which may protect you from oxidative stress related to certain chronic diseases such as (8):
- Cancer (lung, prostate, ovarian, bladder, and breast) (9, 10, 11, 12, 13, 14)
- Heart diseases (15, 16, 17)
- Degeneration of neurons (Alzheimer’s disease) (18, 19)
- Diabetes (type 2) (20)
The prevention of these diseases has been linked to the consumption of a diet high in vitamin A rather than to the use of supplements.
If you want to learn more about carotenoid-rich foods, check out our article here.
3. It is a valuable ally for your defences
Vitamin A is also referred to as the anti-inflammatory vitamin because of its ability to strengthen the immune system (21).
Researchers suggest that vitamin A is involved in the formation and development of cells that work to protect our bodies from infections and autoimmune diseases (where the body attacks itself) (22, 23).
In contrast, individuals with insufficient levels of vitamin A (due to malnutrition or chronic disease) experience far more complications than people with good nutritional status (24, 25).
4. It improves fertility and helps your baby grow
Since vitamin A is fundamental for the growth and maintenance of cells, it is also a vital nutrient for the creation of new life.
This is due to the role that vitamin A plays in the health of reproductive cells (ovules and sperm) (26) and its involvement in the development of the baby and the well-being of the mother during pregnancy.
A deficiency could lead to premature delivery and the development of night blindness in mothers (especially during the third trimester of pregnancy, when they have higher nutritional needs) (27). However, an excess of this vitamin (particularly through the use of supplements) could trigger malformations in the baby and toxicity (28, 29).
How Can You Make the Most of the Properties of Vitamin A?
Learning all the benefits of this vitamin may give you the urge to run to the store shelves and buy any supplement that comes your way. But be very careful! Vitamin A can build up in our bodies and cause a lot of harm.
Follow our recommendations below to learn how to get the most out of vitamin A.
It all starts with your diet
Vitamin A comes from animal foods such as beef and lamb liver, cheese, salmon, eggs, and butter.
On the other hand, provitamin A, which is transformed into vitamin A in our body, can be found in vegetables such as the well-known carrot, canary melon, pumpkin, broccoli, peas, and apricot.
Food will rarely cause vitamin A toxicity, so you can enjoy its properties without fearing the side effects of hypervitaminosis (30).
Take supplements with caution
If you have a condition that makes you vulnerable to vitamin A deficiency such as intestinal problems or chronic illness, your doctor may prescribe vitamin A supplements.
Make sure you follow your doctor’s instructions carefully when taking these supplements, especially when it comes to the daily dose and the length of the supplementation period.
An intake of more than 25,000 IU per day for more than 6 years or more than 100,000 IU/day for more than 6 months is considered a toxic intake. However, some individuals may develop symptoms of hypervitaminosis earlier and with lower doses (31).
Choose the best type of vitamin A for you
There are two types of vitamin A supplements you can choose from depending on your specific needs:
- Preformed vitamin A: You can find it as retinyl palmitate or retinyl acetate. It is available immediately but will accumulate in the liver.
- Provitamin A (beta-carotene): it is transformed into vitamin A whenever the body needs it, preventing it from accumulating and generating hypervitaminosis.
The two types of vitamin A may be combined in the same formulation or with other nutrients to help meet several nutritional needs at once.
Avoid supplements if…
As mentioned earlier, vitamin A supplements should be used only by people who, for whatever reason, cannot obtain enough of this nutrient from their diet or when their body needs more nutrients than it can consume.
In addition, some individuals should refrain from taking vitamin A, as it may have serious consequences on their health (32):
- Individuals on certain medications: anticoagulants, retinoids, weight loss drugs (Orlistat), and drugs metabolised in the liver.
- Pregnant women: avoid taking vitamin A supplements unless prescribed by your doctor, as they could harm you and your baby.
- Children and adolescents: do not give them unless instructed by a paediatrician.
Vitamin A is essential for the functioning of our organs and systems. Through its role in cell formation and its anti-inflammatory properties, this nutrient appears to be involved in the prevention of major diseases such as cancer.
A balanced diet has proven to be the best way to get enough vitamin A and many of its benefits. However, some people cannot rely on a balanced diet to meet their nutritional needs; this is when vitamin supplements come into play to save the day.
Don’t forget to check out our other articles to learn more about nutrition and health! Feel free to leave us a comment with your questions and to share this article.
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