11 Health Benefits of Vitamin A, Deficiency, Food sources and Risks
Obtaining adequate vitamin A is vital for sustaining general health since it is a powerful antioxidant and an essential fat-soluble vitamin. It's important for immunity, bone health, and even the prevention of disease. It also helps to maintain clear, healthy skin.
A lack of this essential vitamin can have some very frightening effects, such as rough skin, stunted growth, and night blindness. Finding the ideal balance is crucial, though, as taking too many supplements can have major side effects like liver and birth disorders.
Vitamin A is necessary for a number of body processes, such as immune system and organ function, good vision maintenance, and womb development of developing children.
The general term for a class of fat-soluble substances that are vital to human health is vitamin A.
Foods derived from plants and animals both include vitamin A molecules, which are known as provitamin A and preformed vitamin A.
What is the Vitamin A?
Despite being viewed as a single nutrient, vitamin A is actually a class of fat-soluble compounds that includes retinol, retinal, and retinyl esters.
Vitamin A is a fat-soluble vitamin that functions in the body as a potent antioxidant. It is essential for preserving brain function, good skin, eyesight, and other body functions. It fights free radical damage to reduce inflammation, much like all antioxidants do.
There are two main types of vitamin A: beta-carotene and active vitamin A, which is also known as retinol and produces retinyl esters. Retinol is a sort of "pre-formed" vitamin A that the body may use straight out of animal-derived meals. The other kind is found in provitamin carotenoids, which are found in vibrant fruits and vegetables.
Provitamin A carotenoids are found in large amounts in plant foods like fruits, vegetables, and oils, but preformed vitamin A, or retinol and retinyl esters, is only found in animal goods like dairy, liver, and fish.
Alpha-, beta-, and beta-cryptoxanthin carotenoids are the inactive forms of provitamin A that are present in plants.
In your body, these chemicals are transformed into their active form. For instance, in your small intestine, beta-carotene is transformed into retinol, an active form of vitamin A.
Your body needs to change these two forms of vitamin A into its active forms, retinal and retinoic acid, in order to use them.
Vitamin A is stored in bodily tissue for potential usage since it is fat-soluble.Your liver stores the majority of the vitamin A in your body as retinyl esters.
After that, these esters are converted to all-trans-retinol, which attaches itself to retinol-binding protein. After that, it gets into your bloodstream, where your body may utilize it.
1-Potent Antioxidant:
Precursors of vitamin A with antioxidant qualities include provitamin A carotenoids, which include beta, alpha, and beta cryptoxanthin.
Your body is shielded by carotenoids from free radicals, which are extremely reactive chemicals that can cause oxidative stress and other health problems.
Chronic illnesses including diabetes, cancer, heart disease, and cognitive loss have all been related to oxidative stress.
Many of these diseases, including diabetes, lung cancer, and heart disease, are linked to diets high in carotenoids.
2-Prevents Age and Night Blindness in Your Eyes Related Decline:
Maintaining the health of your eyes requires vitamin A.
To transform light that enters your eye into an electrical signal that can be transmitted to your brain, you need this vitamin.
In fact, nyctalopia, or night blindness, might be one of the initial signs of a vitamin A deficiency.
People who are deficient in vitamin A may experience night blindness since the vitamin is essential for the production of the pigment rhodopsin.
Your retina contains a substance called rhodopsin, which is incredibly sensitive to light.
While they still have normal vision during the day, people with this syndrome have trouble seeing in the dark because their eyes have trouble detecting low light levels.
Eating enough beta-carotene can help prevent night blindness and slow down the age-related deterioration in vision in certain individuals.
In the industrialized world, age-related macular degeneration, or AMD, is the primary cause of blindness. Its precise etiology is unknown, however oxidative stress-related retinal cellular damage is believed to be the culprit.
According to the Age-Related Eye Disease Study, administering antioxidant supplements, such as beta-carotene, to individuals over 50 who have mild vision impairment decreased their chance of advanced macular degeneration by 25%.
It is commonly known that vitamin A improves vision and maintains the health of your eyes. This is due to the fact that it is an essential part of the rhodopsin molecule, which is what causes vision when light strikes the retina and activates it. One of the main causes of age-related blindness, macular degeneration, can be avoided in part by taking beta-carotene.
3-Promotes the Repair Tissue:
Eating a diet high in vitamin A is essential for tissue healing and cell renewal. Not only is this vitamin essential for maintaining healthy skin, but some research even suggests it may help with wound healing.
For example, a study done at the Department of Dermatology at Drexel University College of Medicine in Philadelphia and published in Dermatologic Surgery indicated that pretreatment with retinoids improved wound healing following facial resurfacing treatments. In a similar vein, an animal model that was published in the Journal of Nutrition found that giving rats extra vitamin A in their diets improved the strength of their wounds after surgery.
4-Prevent Urinary Stone:
If you've ever had urinary stones, you probably know how excruciatingly painful they can be. Usually, urinary stones begin in the kidneys and gradually spread to the ureters or bladder. They may result in symptoms such as hematuria (bloody urine), discomfort, stomach pain, and frequent urination. If left untreated, they may potentially lead to infections, problems, and in rare circumstances, surgical intervention.
In fact, a study conducted The results showed that children with low vitamin A levels had higher levels of calcium oxalate crystals in their urine, which is indicative of a higher risk of urinary stone formation.
5-Can Lower Your Risk of Certain Cancers:
When abnormal cells start to multiply or divide uncontrollably, cancer results.
Scientists are interested in vitamin A's impact on cancer risk and involvement in cancer prevention because it is crucial for the growth and development of your cells.
Higher intakes of beta-carotene, a form of vitamin A, have been associated in observational studies with a lower risk of cervical, lung, and bladder cancer in addition to Hodgkin's lymphoma.
However, while eating a lot of plant-based vitamin A has been related to a lower risk of cancer, the same cannot be said for animal foods, which also include active forms of vitamin A.
Supplemental vitamin A hasn't demonstrated the same positive outcomes either.
In fact, there has been evidence in certain trials that smokers who supplemented with beta-carotene had an increased risk of lung cancer.
Currently, there is still much to learn about the connection between vitamin A levels in the body and the risk of cancer.
However, available data indicates that obtaining enough vitamin A, particularly from plants, is critical for normal cell division and may lower your chance of developing some cancers.
To prevent or reduce the progression of cancer over time, it is recommended to get your retinoic acid through food sources as high levels can be damaging to cells. Furthermore, remember that moderation is key to maximizing the possible health advantages and that sometimes less is better.
6-Supports a Healthy Immune System:
Maintaining the natural defenses in your body is mostly dependent on vitamin A.
This includes the mucous membranes that help keep bacteria and other infectious agents out of your eyes, lungs, stomach, and genitalia.
White blood cells, which aid in clearing bacteria and other Phathogens from your bloodstream, are also produced and functioned by it.
This implies that a vitamin A deficiency may make you more vulnerable to infections and may cause your illness to worsen before getting better.
In fact, it has been demonstrated that treating children's vitamin A deficiency lowers their chance of dying from viruses like malaria and measles, which are widespread in these nations.
An essential component of immunological function, vitamin A may be particularly helpful in preventing disease and infections.
7-Reduces the Risk of Acne:
An inflammatory, long-lasting skin condition is acne.
The face, back, and chest are the most prevalent places for sore patches and blackheads to appear in people with this illness.
The accumulation of oils and dead skin cells in the sebaceous glands causes these lesions. The sebum produced by these glands, which are located in the hair follicles on your skin, is an oily, waxy material that keeps your skin moisturized and waterproof.
Even while the spots are not harmful to the skin, acne can have a negative impact on a person's mental health and cause sadness, worry, and low self-esteem.
It's still unknown exactly what part vitamin A plays in the onset and treatment of acne.
It has been proposed that a vitamin A deficiency may raise your risk of acne because it causes your hair follicles to overproduce the keratin protein.
Because it would be more difficult for dead skin cells to be eliminated from hair follicles, blockages would result, increasing your risk of acne.
Prescriptions are now required for some vitamin A-based acne treatments.
One oral retinoid that works well for treating severe acne is isotretinoin. Nevertheless, this drug must only be administered under medical supervision due to its potentially dangerous side effects.
Vitamin A has anti-inflammatory qualities that make it effective in treating a variety of skin conditions, including retinaldehyde. Retinoids may actually be helpful for common skin problems like acne, eczema, and psoriasis, according to studies.
8-Inflammation Relief:
In the body, beta-carotene functions as a potent antioxidant, preventing inflammation, oxidative cell damage, and the accumulation of dangerous free radicals.
Since inflammation is the primary cause of many chronic illnesses, including diabetes, heart disease, and cancer, the anti-inflammatory properties of beta-carotene and vitamin A can have a significant impact on a variety of health issues. Decreased inflammation is also associated with improved outcomes for inflammatory disorders like Crohn's disease and rheumatoid arthritis, as well as a decreased risk for neurological diseases like Alzheimer's and Parkinson's.
9-Supports Bone Health:
The three basic nutrients—protein, calcium, and vitamin D—are essential for keeping your bones strong as you age.
On the other hand, enough consumption of vitamin A is also required for healthy bone formation, and low levels of this vitamin have been associated with weak bones.
In actuality, those with normal blood levels of vitamin A are less likely to experience bone fractures than those with lower levels.
Furthermore, a recent meta-analysis of observational studies discovered that those who consumed the most total vitamin A in their diets saw a 6% lower incidence of fractures.
Nevertheless, when it comes to bone health, low vitamin A levels might not be the only issue. According to certain research, persons who consume large amounts of vitamin A are also more likely to have fractures.
Nevertheless, since observational studies constitute the foundation of all of these conclusions, causality cannot be established.
Thus, further controlled trials are required to corroborate the findings of observational research and to completely understand the existing relationship between vitamin A and bone health.
Remember that the availability of other important nutrients, such as vitamin D, also affects your risk of fractures, so your vitamin A status is not the only factor that impacts your risk.
10-Reduces Cholesterol:
All over the body, cholesterol is a waxy, fat-like molecule. Because cholesterol is essential for hormone manufacturing and serves as the building block of cell membranes, it is necessary for your body to function properly. On the other hand, excessive cholesterol accumulation can constrict and harden your blood vessels, raising your risk of heart disease.
Getting enough vitamin A in your diet may help naturally lower cholesterol levels to maximize heart health, despite the paucity of human studies on the subject. For example, in a Brazilian animal model, rats given beta-carotene supplements for six weeks saw a substantial reduction in blood levels of total cholesterol.
11-Promotes Healthy Growth and Reproduction:
Both men and women need vitamin A to have a healthy reproductive system, and it is also necessary for the appropriate growth and development of embryos throughout pregnancy.
The growth and development of the fetus's key organs and systems, such as the skeleton, nervous system, heart, kidneys, eyes, lungs, and pancreas, are also influenced by vitamin A in pregnant women.
However, excessive vitamin A intake during pregnancy can also be detrimental to the developing infant and may result in birth abnormalities, even though it is far less prevalent than vitamin A deficiency.
Vitamin A is regarded as one of the greatest vitamins for women specifically and is essential for healthy growth and development at all stages of life. A shortage of this important vitamin has been associated with weakened immune system, increased morbidity and mortality, and even an increased chance of HIV-1 transmission from mother to child in pregnant women.
One of the most crucial micronutrients for lung development and function during pregnancy, according to the American Pediatrics Association, is vitamin A. Additionally important in preventing developmental abnormalities in women who are pregnant or nursing is beta-carotene.
Deficiency:
Vitamin A deficiency is widespread in underdeveloped nations where people may not have as much access to food sources of preformed vitamin A and provitamin A carotenoids.
A lack of vitamin A can have serious negative effects on one's health.
- The World Health Organization states that the most common preventable cause of blindness in children globally is a vitamin A deficiency.
- Moreover, diarrhea and the measles have a higher severity and mortality rate when there is a vitamin A deficiency.
- Furthermore, studies have shown that vitamin A deficiency harms the developing fetus by reducing its growth and development and increases the risk of anemia and death in pregnant women.
- Vitamin A deficiency can cause less severe symptoms, such as acne and hyperkeratosis on the skin.
- A vitamin A deficit is more common in some populations, including premature infants, those with cystic fibrosis, and women who are pregnant or nursing in developing nations.
Food Sources:
Provitamin A and preformed vitamin A carotenoids are widely available in food.
Compared to plant-based sources of provitamin A carotenoids, your body can absorb and use preformed vitamin A more easily.
The efficient conversion of carotenoids, such beta carotene, by your body into active vitamin A is influenced by a variety of factors, including as your genetic makeup, nutrition, general health, and medications.
This is why those who eat a plant-based diet, especially vegans, need to be careful to get enough foods high in carotenoids.
The foods that contain the most preformed vitamin A are:
- Beef Liver
- Egg Yolks
- Liverwurst
- Butter
- Cod Liver Oil
- Salmon
- Cheddar Cheese
- Liver Sausage,
- King Mackerel Trout
- Chicken Liver
Foods rich in beta carotene and other provitamin A carotenoids include:
Recommended Intake:
The amount of vitamin A that is recommended depends on age. Additionally, during pregnancy and nursing, people require more.
It comes in a variety of forms, and retinol activity equivalents (RAEs) are a common way to assess how much vitamin A is in food.
One RAE corresponds to:
One microgram (mcg) of retinol
12 mcg of beta-carotene from food
From supplements, 2 mcg of beta-carotene
Amount in international units: 3.33 vitamin A
The suggested daily allotmentsAmong the reliable sources of vitamin A according to age are:
400 mcg for up to 6 months
7–12 months: 500 mcg
1-3 years: 300 mcg
4–8 years: 400 mcg
9–13 years: 600 mcg
14 years and older: 700 mcg for women and 900 mcg for men
The daily requirement is 770 mcg during pregnancy. The daily dosage for nursing mothers is 1,300 mcg.
According to data from the 2007–2008 National Health and Nutrition Examination Survey, the average American, 2 years of age and older, takes in 607 micrograms of vitamin A day.
Risks:
The high concentrations of preformed vitamin A (retinol) present in certain supplements may be the cause of vitamin A toxicity rather than a deficit in the United States. Additionally, because vitamin A is fat-soluble, any excess that the body does not require right away is absorbed and stored in the liver or fat tissue. It can turn poisonous if stored in excess. It is considered safe to consume up to 3,000 mcg of preformed vitamin A on a tolerated upper limit, which is more than three times the current recommended daily dosage. There is evidence, nevertheless, that consuming this much preformed vitamin A may raise the risk of hip fractures, bone loss, and some birth defects.
The potential for preformed vitamin A to obstruct the advantageous effects of vitamin D is another reason to limit intake. Toxicological indicators include the following.
- Vision abnormalities include blurry sight
- Bone pain
- Vomiting
- Nausea
- Dry skin
- Light sensitivity, such as sunlight
Unlike preformed vitamin A, beta-carotene does not cause toxicity even when consumed in large quantities. As with preformed vitamin A, the body can produce vitamin A from beta-carotene as needed, thus intake levels don't need to be watched. Since many multivitamin producers have already lowered the quantity of preformed vitamin A in their products, it is advisable to select a multivitamin supplement that contains all or the vast majority of its vitamin A in the form of beta-carotene. But most people don't really need to take high-dose beta-carotene supplements on their own. Since certain randomized trials in smokers have associated high-dose supplements with an increased risk of lung cancer, smokers in particular should stay away from these.
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