Vitamin A is also known as Retinol, the miracle vitamin. It’s a miracle vitamin especially for females as it is behind a radiant, clear and smooth skin and thick, strong and shiny hair. Vitamin A is also an essential micronutrient. An essential vitamin means it’s not produced naturally by the body or the gut microbiota and should be taken from animal or plant sources. Micronutrient means the body only needs a tiny amount of it compared with other nutrients, such as carbohydrates, proteins, and fats. Vitamin A is measured by micrograms (μg, mcg), not milligrams (mg). It is a fat-soluble vitamin, best absorbed along with fat-rich food, and it is stored within fat cells inside the body. Provitamin A is called carotenoids have over 600 kinds.
Vitamin A plays a significant role in eye health, which makes its deficiency very dangerous, as it may lead to irreversible blindness. Thus, it is important to increase our knowledge about this vitamin and understand how it works, how to treat and prevent its deficiency and the consequences that come after that.
Why vitamin A, and what benefits does it have?
• Acts as antioxidant
Antioxidants are substances that reduce and remove harmful molecules from cells to protect them from aging and degeneration. Vitamin A is an excellent source for antioxidants; it delays the aging processes, reducing the incidence of premature aging, the appearance of wrinkles, and at the same time protects against cancers because it supports cell growth and differentiation.
• Protect the vision
It has a critical role in protecting eyesight, as it is an essential component of a retinal protein that helps absorbing light in retinal receptors. Thus, adequate vitamin A intake can reduce the risk of macular degeneration by 25%.
• Helps with the immune system
• Important for the skin
It is an all-round skin savior. It improves the appearance of dry skin, speeds up the healing process of wounds, fights acne and reduces the signs of premature aging. Topical vitamin A helps with acne, reduces wrinkles and pigmentation, boosts collagen and hydration, and helps against skin cancer.
• Essential for fetus development
That is because vitamin A plays a significant role in regulating cell development and brain growth. However, vitamin A supplements intake should be monitored during pregnancy as it may increase vitamin A over the limit and lead to birth deformities, which are mainly neural tube defects.
• Helps with infertility
It is essential for the maintenance of both male and female reproductive systems. Vitamin A helps with spermatogenesis and the development of the fetus. Some studies have shown that females with infertility have a better chance to conceive after adequate intake of vitamin A.
• Helps with anemia
Because it metabolizes and releases stored iron with the body to make it available to use.
• Important for bone growth
Vitamin A is essential for the growth of osteoblasts, the building unit of the bone, and it helps with calcium deposition in the bone.
• Good for hair
It is responsible for hair cell growth. Vitamin A helps to moisturize the scalp as it produces the sebum, an oily substance. It also reduces hair breakage, giving rise to a shiny, thicker, fuller hair while preventing scalp dryness, which protects against hair loss.
Where can I get vitamin A from?
Vitamin A is a term that has two categories, retinol, and carotenoids. Retinol is vitamin A from animal products. On the other hand, carotenoids come from plant products. Dietary sources of retinol include beef, chicken liver, fatty fish and shrimp, butter, milk, egg yolk, cheese, and cod liver oil. The dietary sources of carotenoids include carrots, sweet potato, bell peppers, tomatoes, kale, and parsley.
Here are some of the highest vitamin A sources and the amount of vitamin A in 100 grams of each source:
- Sweet potato: 1922 μg, 214% of daily vitamin A intake.
- Carrots: 1329 μg, 148% of daily vitamin A intake.
- Tuna: 1287 μg, 143% of daily vitamin A intake.
- Butternut Squash: 1144 μg, 127% of daily vitamin A intake.
- Spinach: 943 μg, 105% of daily vitamin A intake.
- Cantaloupe: 299 μg, 33% of daily vitamin A intake.
- Lettuce: 205 μg, 23% of daily vitamin A intake.
How do our bodies absorb vitamin A?
As mentioned before, vitamin A has two main categories: retinoids, the active form of vitamin that is found in animal products, and carotenoids or provitamin A, found in plants products.
Retinoids are the active form, and it is ready to be used, while carotenoids are provitamin A, and must be converted first to retinol so the body can use it. Some people can’t convert carotenoids to their active forms, as in infants, diabetic patients, people on a low-fat diet, and any condition that interferes with fat absorption.
Retinoids and carotenoids contain different elements, and every element has its own health benefits. Rotenoids contain retinol, the active form of vitamin A, which converts into retinal, retinoic acid and retinyl esters. Retinal is responsible for eye health; retinoic acid is essential for the skin, bone and teeth health, and retinyl esters is an inactive form of retinoids. Carotenoids contain carotenes, such as alpha, beta, gamma, delta, epsilon, and zeta carotene. Alpha-carotene is an antioxidant, while beta carotene is the provitamin that converts into retinol.
How much vitamin A do I need daily?
Vitamin A daily recommendations differ according to age, sex, daily activity, person status of health, metabolic, and medical conditions. However, the recommended vitamin A amounts according to the World Health Organization (WHO) are:
- From birth to 6 months: 400 μg
- Infants from 7 to 12 months: 500 μg
- Children from 1 to 3 years: 300 μg
- Children from 4 to 8 years: 400 μg
- Children from 9 to 13 years: 600 μg
- Teens from 14 to 18 years: 900 μg
- Male adult from 19 to 50 years: 900 μg
- Female adult from 19 to 50 years: 700 μg
- Pregnant teens: 750 μg
- Breast-feeding teens: 1200 μg
- Pregnant women: 770 μg
- Breastfeeding women: 1300 μg
- Male seniors from 50 years and older: 900 μg
- female seniors from 50 years and older: 700 μg
People at risk of vitamin A deficiency may need more than the daily vitamin A recommendation.
Who is at risk, and what are the causes of vitamin A deficiency?
Pregnancy and breast-feeding women are at risk because of the nutritional demand of the infant, which increases the use of vitamin A in the body and may cause vitamin A deficiency for the mother when it’s not prevented with supplements or increased in food rich in vitamin A.
○ Low vitamin A diet and restricted vegans
Plant-based diets are structured around plants that contain carotenoids only. Carotenoids need to be converted to retinol so the body can benefit from it. Some people don’t convert carotenoids, and having such a diet may lead to vitamin A deficiency in their case when it is not combined with animal products.
○ Fat malabsorption
This is because vitamin A is a fat-soluble vitamin, and its absorption is facilitated by fat. Without fat absorption, there will be inadequate vitamin A absorption, leading to its deficiency.
○ Poor vitamin A absorption
When do you consider vitamin A deficiency?
Normal vitamin A ranges are 15 to 60 micrograms per deciliter (μg/dl). This test is usually called vitamin A or retinol test. Before the blood test, the patient should fast for 24 hours. It is considered a vitamin A deficiency when the results are below 15 μg/dl.
How do you know that you have vitamin A deficiency and when you need to seek professional advice?
Vitamin A deficiency is rare in developed countries, but it is common in children under the age of 5 and pregnant women in developing countries. Research shows that more than 800,000 deaths worldwide are associated with vitamin A deficiency.
♦ Dry skin, eyes, and lips
Vitamin A is responsible for normal cell growth, maturation, and differentiation. Its deficiency is more apparent on highly dividing cells, as in epithelial tissues in the skin and cornea or mucous membranes in the lip and mouth. It changes the moisture content of the skin, gives rise to certain conditions like acne, psoriasis, and eczema.
♦ Night blindness
Vitamin A is a significant compound in Rhodopsin, which is a retinal protein responsible for absorbing lights in the retinal receptor. Vitamin A deficiency affects sight in two ways, first affects the synthesis of rhodopsin, leading to a reduction of light absorption by the retinal receptor. Secondly, it dries up the cornea, leading to hazy vision. Night blindness is an early symptom of vitamin A deficiency, and may lead to irreversible blindness if it is not treated as early as possible.
Vitamin A is responsible for cell growth and maturation. Vitamin A deficiency may reduce cell division, growth, and maturation in the reproductive organs, leading to infertility.
♦ Impaired immunity and increase infections
It impairs immunity by reducing the normal regeneration of the epithelium and mucous membrane, which impairs the natural defense mechanism of the body against bacteria and viruses.
♦ Bitot’s spots
They are a characteristic symptom and can only be found with vitamin A deficiency. They are spots of keratinization in the conjunctiva; they can have different shapes and sizes and are associated with corneal dryness.
How to maintain vitamin A at a healthy level and prevent vitamin A deficiency?
– Eat food that rich in vitamin A, especially from animal sources as in beef, chicken liver, fatty fishes and shrimp, butter, milk, egg yolk, cheese, and cod liver oil. You can also include in your diet foods such as carrots, sweet potato, bell peppers, tomatoes, kale, and parsley.
– Increase your fat in diets along with food that contains vitamin A to increase its absorption.
– Treat medical conditions that affect vitamin A metabolism like Crohn’s, cystic fibrosis, pancreatitis, celiac and liver diseases.
– Use vitamin A supplements, especially in people how are at risk of vitamin A deficiency as vegans, pregnant and breastfeeding women and children under 5 years.
– Avoid alcohol as it decreases vitamin A absorption and beta carotene conversion.
How can you treat vitamin A deficiency?
– You should increase vitamin A levels in the blood by working on the same points as in the prevention of vitamin A deficiency. You can ask your doctor as he may recommend vitamin A supplements to increase vitamin A levels. Vitamin A supplements are available over the counter, and for most adults the recommended daily allowance is 700 μg.
– Always ask your doctor before taking supplements, even if it is available over the counter. Vitamin A supplements can cause toxicity and should be closely monitored because it is a fat-soluble vitamin and stored inside the body.