Vitamin A is the common name for a group of fat-soluble compounds that are essential for human health. They are essential for many processes in your body, including maintaining a healthy outlook, ensuring normal functioning of your immune system and organs, and helping proper growth and development of babies in the womb.
It is recommended that men receive 900 mcg, women 700 mcg with children, and 300-600 mcg of vitamin A a day. Vitamin A is found in animal and plant foods and comes in two different forms: pre-made vitamin A and provitamin A.
Pre-made Vitamin A is known as an active form of the vitamin, which your body can use as it is. It is found in animal products including meat, poultry, fish, and milk, and includes compounds retinol, retinal and retinoic acid.
Provitamin A carotenoids – alpha-carotene, beta-carotene, and beta-cryptoxanthin – are inactive forms of vitamins found in plants.
These compounds are converted into an active form in your body. For example, beta-carotene is converted to retinol (an active form of vitamin A) in your small intestine.
Source of Vitamin A
There are two types of vitamin A. Vitamin A, also known as retinol, is found in animal products. Good sources are milk, eggs, meat, cheese, liver, halibut fish oil, cream, and kidneys. According to the National Library of Medicine (NLM) in the United States, pro-vitamin A is found in plant-based foods such as fruits and vegetables. The most common type of pro-vitamin A is beta carotene, a carotenoid that produces dark pigments in plant foods.
Beta carotene is found in these brightly colored foods:
- Pink grapefruit
- Sweet potatoes
- Winter squash
- Dark green, vegetables
Health Benefits of Vitamin A
Protecting Your Eyes From Night Blindness and Age-Related Depression
Vitamin A is essential for keeping your eyes peeled. Vitamins are needed to convert the light that strikes your eye into an electrical signal that can be sent to your brain.
In fact, one of the first symptoms of vitamin A deficiency can be night blindness, known as nyctalopia.
Night blindness comes from people with vitamin A deficiency, as the vitamin is a major component of the pigment rhodopsin.
Rhodopsin is found in the retina of your eye and is very sensitive to light.
People with this condition can still see normally during the day, but reduce their vision in the dark as their eyes struggle to find the light at lower levels.
In addition to preventing night blindness, eating a sufficient amount of beta-carotene can help reduce eye loss that some people experience as they grow older.
Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world. Although its exact cause is unknown, it is thought to be the result of damage to cells in the retina, caused by oxidative stress.
The Age-Related Eye Disease Study found that giving people over the age of 50 with dementia an antioxidant supplement (including beta-carotene) reduced the risk of developing macular degeneration by 25%.
However, a recent Cochrane review found that beta-carotene supplements alone will not prevent or delay eye loss caused by AMD.
It May Reduce Your Risk of Cancer
Cancer occurs when abnormal cells begin to grow or divide uncontrollably.
Since vitamin A plays a vital role in the growth and development of your cells, its influence on cancer risk and ice protection against cancer is appealing to scientists.
In experimental studies, eating high levels of vitamin A in the form of beta-carotene has been linked to a reduced risk of certain types of cancer, including Hodgkin’s lymphoma, as well as cervical, lung, and other cancers.
However, although high levels of vitamin A from plant extracts have been linked to reduced cancer risk, animal diets containing active forms of vitamin A have not been linked in the same way.
Similarly, vitamin A supplements have not shown the same beneficial effects.
In fact, in some studies, smokers who took beta-carotene supplements had an increased risk of lung cancer.
At present, the link between vitamin A levels in your body and the risk of cancer is not well understood.
However, current evidence suggests that adequate vitamin A supplementation, especially in plants, is essential for healthy cell division and may reduce the risk of certain types of cancer.
Supports a Healthy Immune System
Vitamin A plays an important role in maintaining your body’s natural defenses. These include obstructions in your eyes, lungs, intestines, and genitals that help catch germs and other infections.
It is also involved in the production and functioning of white blood cells, which help to capture and eradicate bacteria and other pathogens from your bloodstream.
This means that vitamin A deficiency can increase your risk of disease and delay your recovery.
In fact, in countries where common diseases such as measles and malaria are common, the correction of vitamin A deficiency in children has been shown to reduce the risk of death from these diseases.
Reduces Your Risk of Acne
Acne is a chronic, inflammatory disease of the skin. People with this condition have painful spots and dark heads, especially on the face, back and chest.
These areas occur when the dominant glands block the skin and fat. These glands are found in the hair follicles on your skin and produce sebum, an oily substance, and wax that keep your skin moisturized and waterproof.
Although spots are harmless to the body, acne can have a profound effect on people’s mental health and lead to low self-esteem, anxiety, and depression.
The exact role that vitamin A plays in the formation and treatment of acne remains unclear.
It has been suggested that vitamin A deficiency can increase the risk of acne, as it causes excessive protein production of keratin in your hair follicles.
This will increase your risk of acne by making it more difficult for dead skin cells to be removed from the hair follicles, leading to blockage.
Some vitamin-A-based supplements for acne are now available with a prescription.
Isotretinoin is one example of an oral retinoid that works in the treatment of severe acne. However, this drug can have serious side effects and should only be taken under medical supervision.
Supports Orthopedic Health
Necessary nutrients to keep bones healthy as you age, are protein, calcium, and vitamin D.
However, adequate vitamin A intake is also necessary for proper bone growth and development, and deficiency of this vitamin has been linked to poor bone health.
In fact, people with low levels of vitamin A are at greater risk for osteoporosis than people with healthy levels.
Additionally, a recent meta-analysis of experimental studies found that people with very high levels of vitamin A in their diet had a 6% reduced risk of cracking.
However, low levels of vitamin A may not be a problem only when it comes to bone health. Some studies have found that people with high vitamin A intake have a higher risk of fractures.
However, these findings are all based on observational studies, which can determine cause and effect.
This means that at present, the link between vitamin A and bone health is not fully understood, and highly controlled trials are needed to confirm what has been observed in observational studies.
Remember that vitamin A status alone does not determine the risk of fracture, and the effect of the presence of other essential nutrients, such as vitamin D, also plays a role.
Promotes Healthy Growth and Rebirth
Vitamin A is essential for maintaining a healthy reproductive system in both men and women, as well as ensuring normal growth and development of embryos during pregnancy.
Studies in rats examining the importance of vitamin A in male reproduction have shown that deficiency inhibits the growth of sperm cells, resulting in infertility.
Similarly, animal studies have suggested that vitamin A deficiency in women can affect fertility by reducing egg quality and affecting egg implantation.
In pregnant women, vitamin A is involved in the growth and development of many major organs and structures in the unborn child, including bones, nervous system, heart, kidneys, eyes, lungs, and pancreas.
However, although it is more common than vitamin A deficiency, too much vitamin A during pregnancy can be harmful to a growing baby and can lead to birth defects.
Therefore, many health authorities recommend that women avoid foods high in vitamin A, such as pâté and liver, and supplements that contain vitamin A during pregnancy.
Taking Too Many Vitamins Can Be Dangerous
Vitamin A is a fat-soluble vitamin, which is stored in your body. This means that overuse can lead to toxic levels.
Hypervitaminosis A is caused by eating too much vitamin A in your diet or vitamin-containing supplements.
Symptoms can include nausea, dizziness, headache, pain, and even death.
Although it can be caused by overeating, this is rare compared to the overuse of supplements and medications.
Also, consuming too much provitamin A in its plant does not have the same risks, as its conversion to the active form in your body is controlled.
Vitamin A Side Effects
When taken by mouth
Vitamin A is preferred for less than 10,000 units (3,000 mcg) daily for most people. Note that Vitamin A is available in two different forms: Preformed Vitamin A and Provitamin A. A single dose of 10,000 10,000 per day is only related to pre-formed vitamin A, some supplements are a form of elements that contain both pre-formed and provitamin.
For these supplements, preformed vitamin A should be used to determine if the amount of vitamin A is safe. In some cases, vitamin A supplements containing more than 10,000 units of vitamin A supplements may still be safe if a portion of the vitamin A is in the form of provitamin A.
For example, a supplement containing 23,000 units of vitamin A, of which 60% in the form of provitamin A, will still be safe. Because vitamin A contains only 40% of its components or 9,200 units of pre-formed vitamin A.
Vitamin A is probably unsafe if taken orally in doses of more than 10,000 units (3,000 mcg) per day. Some studies suggest that higher doses increase the risk of osteoporosis and hip fractures, especially in the elderly.
Adults eat low-fat dairy foods, which are protected by vitamin A, and plenty of fruits and vegetables usually do not require vitamin A supplements or multivitamins that contain vitamin A.
Long-term use of vitamin A can lead to fatigue, nausea, mood swings, anorexia, abdominal discomfort, nausea, vomiting, mild fever, excessive sweating, and many other side effects. The risk of hip fractures may increase.
Concerns are also growing that taking high doses of antioxidant supplements such as vitamin A can do more harm than good. Some studies show that taking high doses of vitamin A supplements can increase the risk of death from all causes and possibly other serious side effects.
If applied to the skin
Vitamin A is probably safer when used on short-term skin. Retinol 0.5% serum is used daily for up to 12 weeks without serious side effects.
When given a shot
Vitamin A is probably safe when giving a muscle shot less than 10,000 units (3,000 mcg) daily.
What is vitamin A good for?
Vitamin A is a fat-soluble vitamin that is naturally present in many foods. Vitamin A is important for normal vision, the immune system, and reproduction. Vitamin A also helps the heart, lungs, kidneys, and other organs work properly.
Can I take vitamin A everyday?
When taken by mouth: Vitamin A is LIKELY SAFE for most people in amounts less than 10,000 units (3,000 mcg) daily. Keep in mind that vitamin A is available in two different forms: preformed vitamin A and provitamin A. The maximum daily dose of 10,000 units per day relates to only pre-formed vitamin A.
Does vitamin A help immune system?
Vitamin A plays a vital role in maintaining your body's natural defenses. This includes the mucous barriers in your eyes, lungs, gut, and genitals which help trap bacteria and other infectious agents.
Does Vitamin A stay in the body?
The vitamins A, D, E, and K are fat-soluble, which means they can be stored in the body. Taking high doses of these vitamins, especially vitamin A, over a long period of time can result in harmful levels in the body unless you have a medically diagnosed deficiency.