Vitamin A, also known as retinol, is a fat-soluble vitamin that is essential to our health. It promotes good vision, especially in low light. Vitamin A promotes normal growth and health of body cells and keeps skin healthy and is needed for the proper development of an embryo and fetus. It may also be needed for reproduction and breast-feeding. It also helps keep skin and mucous membranes that line the nose, sinuses, and mouth healthy. It plays a role in immune system function, growth, bone formation, reproduction, and wound healing.
There are animal sources (retinoids, which includes retinol) and vegetable sources (carotenoids, which includes beta-carotene) of vitamin A in foods. Only a few of the carotenoids in foods are converted to vitamin A in the body. Beta-carotene is the most familiar carotenoid that the body converts to vitamin A. It can be found in many fruits, vegetables, eggs, whole milk, butter, fortified margarine, meat, and oily saltwater fish. It can also be made in a laboratory.
Beta-carotene, like several other carotenoids, acts as an antioxidant. Antioxidants protect cells from damage caused by substances called free radicals. Free radicals are believed to contribute to certain chronic diseases and play a role in the aging processes. Antioxidants help slow or prevent this cell damage. By protecting cells from damage, antioxidants may reduce risk for certain cancers and heart disease.
While vitamin A is essential for good health, it can be toxic in high doses. Never take more than the recommended daily allowance without first talking to your doctor.
Vitamin A is used for treating vitamin A deficiency. It is also used to reduce complications of diseases such as malaria, HIV, measles, and diarrhea in children with vitamin A deficiency.
Women use vitamin A for heavy menstrual periods, premenstrual syndrome (PMS), vaginal infections, yeast infections, "lumpy breasts" (fibrocystic breast disease), and to prevent breast cancer. Some women with HIV use vitamin A to decrease the risk of transmitting HIV to the baby during pregnancy, childbirth, or breast-feeding.
Men use vitamin A to raise their sperm count.
Some people use vitamin A for improving vision and treating eye disorders including age-related macular degeneration (AMD), glaucoma, and cataracts.
Vitamin A is also used for skin conditions including acne, eczema, psoriasis, cold sores, wounds, burns, sunburn, keratosis follicularis (Darier's disease), ichthyosis (noninflammatory skin scaling), lichen planus pigmentosus, and pityriasis rubra pilaris.
It is also used for gastrointestinal ulcers, Crohn's disease, gum disease, diabetes, Hurler syndrome (mucopolysaccharidosis), sinus infections, hayfever, and urinary tract infections (UTIs).
Vitamin A is also used for shigellosis, diseases of the nervous system, nose infections, loss of sense of smell, asthma, persistent headaches, kidney stones, overactive thyroid, iron-poor blood (anemia), deafness, ringing in the ears, and precancerous mouth sores (leukoplakia).
Other uses include preventing and treating cancer, protecting the heart and cardiovascular system, slowing the aging process, and boosting the immune system.
Vitamin A is applied to the skin to improve wound healing, reduce wrinkles, and to protect the skin against UV radiation.
Vitamin Promotes healthy vision. It helps produce the pigments in the retina of the eye, vitamin A plays a big part in giving you healthy eyesight. It prevents night blindness and even helps you see in colour.
Vitamin A also boosts our immunity and aids the body's immune system to ward of infections.
Vitamin A is known to enhance the function of white blood cells, promotes response of antibodies and antigens -- thereby strengthening the immune system's defence against disease and infection.
Vitamin A is essential for reproductive processes in both men and women. It also helps maintain healthy skin, teeth, skeletal and soft tissues, and mucus membranes.
The antioxidant properties of vitamin A combat free radicals that can damage the skin through oxidative stress. By maintaining proper moisture retention, the skin is not only protected from common dryness, but also keratinization (the process in which the epidermis hardens into a heavy material that makes up hair and nails), psoriasis (a skin disease marked by red, itchy or scaly patches), acne, and even wrinkling.
Prescription creams and pills containing retinoids, a synthetic form of vitamin A, are used to help clear up severe acne and psoriasis and have shown promise for treating other skin disorders, premature aging from the sun and warts. These medications require close supervision by a doctor. Isotretinoin (Accutane), an oral medication for acne, can cause very serious side effects and must not be used by pregnant women or women of child-bearing age.
When converted into retinoic acid, vitamin A effectively maintains healthy bones and teeth. Dentin, which also requires vitamin A, forms the hard layer of material within our teeth, thereby ensuring their strength. Vitamin A also plays an important role in replacing worn out or old tissue with newer tissue to ensure healthy bones and teeth.
Getting enough vitamin A in your diet is essential for good vision. Research shows that people who eat more foods with vitamin A are less likely to develop age-related macular degeneration. In addition, a large population study found that people who got high levels of vitamin A though their diets had a lower risk of developing cataracts. But researchers don't know whether taking vitamin supplements would work the same way. Vitamin A supplements may help slightly slow down the damage from retinitis pigmentosa, a hereditary disease that causes poor night vision. The study used high doses, however, which can be toxic.
For children who have vitamin A deficiency, supplements can reduce the severity and complications of measles. Children who are deficient in vitamin A are more likely to develop infections, including measles. In areas of the world where vitamin A deficiency is widespread or where at least 1% of those with measles die, the World Health Organization recommends giving vitamin A supplements to children who have measles. However, vitamin A does not seem to help unless a child has vitamin A deficiency. Never give a child vitamin A supplements without a doctor's supervision.
People with IBD, both ulcerative colitis and Crohn's disease -- may have a hard time absorbing all the nutrients their bodies need. Health care providers often recommend that people with IBD take a multivitamin, including vitamin A.
Urinary calculi, or solid particles in the urinary system, may cause pain, nausea and vomiting when stones are formed. Vitamin A produces a mineral compound within the body called calcium phosphate that prevents the formation of these solid particles.
Whether vitamin A can reduce the risk of cancer is not clear. People who eat a healthy diet with enough beta-carotene and other carotenoids from fruits and vegetables seem to have a lower risk of certain cancers, such as breast, colon, esophageal, and cervical cancer. And some laboratory studies suggest that vitamin A and carotenoids may help fight certain types of cancer in test tubes.
One preliminary study suggests that a topical form of vitamin A may reduce abnormal growth of cells on the cervix, called cervical neoplasia.
Researchers are also investigating retinoids, a synthetic form of vitamin A, for skin cancer. People with certain types of skin cancer tend to have lower levels of vitamin A and beta-carotene in the blood. However, studies that have looked at whether taking higher amounts of vitamin A or beta-carotene would prevent or treat skin cancer have had mixed results.
If you don't get enough vitamin A, you are going to develop a vitamin A deficiency, and more likely get sick. Vitamin A is essential to overall good health and individuals that do not get an adequate amount of vitamin A in their diet have been shown to be more vulnerable to infection and infectious diseases.
Inadequate intake of vitamin A can cause night blindness, dry, scaly skin, poor growth, and increased risk for infections such as respiratory infections, urinary tract infections, including AIDS, measles, bronchitis, yeast infections, and boils or abscesses.
A deficiency in vitamin A could also lead to a variety of skin disorders; such as psoriasis, rashes, rosacea, and warts
Other symptoms of vitamin A deficiency include dry eyes, reduced night vision, eye inflammation, distorted color vision or overall decrease in the quality of vision, diarrhea, loss of taste or smell, loss of appetite, poor balance, and growth retardation in children.
Vitamin A deficiency is a result of prolonged consumption of food with insufficient beta-carotene and vitamin A. In the western world it most often happens in people with diseases affecting the ability of intestines to absorb fat, as well as in alcoholics. The diseases that may contribute to vitamin A deficiency are celiac disease, cholestasis and cystic fibrosis. Vitamin A deficiency is widespread in Southeast Asia where the one of the most important parts of their diet, rice, is lacking in vitamin A.
The earliest symptom of vitamin A deficiency is night blindness whereas more prolonged vitamin A deficiency usually results in drying of the conjunctiva. If not treated this may finally result in the cornea. If the vitamin A deficiency still continues cornea will shrivel up and become ulcerated. In the end infection and inflammation occur in the interior of the eye which leads to total and irreversible blindness.
Recommended intakes for vitamin A are given as "Retinol Activity Equivalents" (RAEs).
Using RAEs helps account for the difference in activity between carotenoids and retinol. It takes about 12 units of beta-carotene or 24 units of other carotenoids to make 1 unit of retinol in the body.
The following table lists the RAEs for vitamin A:
|
Life Stage |
Vitamin A (μg/day as RAE) |
|
Men, ages 19+ |
900 |
|
Women, ages 19+ |
700 |
|
Pregnancy |
770* |
|
Breastfeeding |
1300 |
|
μg= micrograms RAE= Retinol Activity Equivalents |
|
|
*Pregnant women should avoid supplemental, preformed vitamin A. |
|
We get vitamin A by eating a variety of fruits and vegetables that contain carotenoids, and from dairy products fortified with vitamin A.
Vitamin A, in the form of retinyl palmitate, is found in beef, calf, and chicken liver; eggs; fish liver oils; and dairy products, including whole milk, whole milk yogurt, whole milk cottage cheese, butter, and cheese.
The body can also make vitamin A from beta-carotene and other carotenoids, fat-soluble nutrients found in fruits and vegetables that give them their color. Most dark-green leafy vegetables and deep yellow/orange vegetables and fruits -- sweet potatoes, carrots, pumpkin and other winter squashes, cantaloupe, apricots, peaches, and mangoes -- contain substantial amounts of beta-carotene. By eating these beta-carotene rich foods, you can increase levels of vitamin A in your body.
Here are some foods and the amount of vitamin A they contain:
|
Food |
Vitamin A (RAE*) |
|
Sweet potato, cooked, 1 medium |
1400 |
|
Carrot, raw, 1 medium |
600 |
|
Pumpkin, cooked, ½ cup |
305 |
|
Cantaloupe, cubed, 1 cup |
270 |
|
Milk, low fat, with vitamin A, 1 cup |
140 |
|
Broccoli, pieces, cooked, 1 cup |
120 |
|
Apricots, 3 medium |
105 |
|
Egg, cooked, 1 large |
85 |
|
Cheese, Cheddar, 1 ounce |
75 |
|
*Retinol Activity Equivalents |
|
We don't need supplements since vitamin A is so widely available in foods and is easily stored in the body. Pregnant women especially should avoid taking retinol supplements.
High doses during pregnancy can cause birth defects. Look for beta-carotene as the only vitamin A source in prenatal supplements.
Taking large doses of retinol can cause nausea, vomiting, headache, and dry scaly skin. More severe health problems from storing excess vitamin A in the body are liver damage, osteoporosis, and nervous system disorders. Vitamin A toxicity can kill you! Keep your total vitamin A intake less than 3,000 μg per day from retinol. Vitamin A from foods is considered safe, but you can get too much from supplements.
Vitamin A supplements are available as either retinol or retinyl palmitate.
Tablets or capsules are available in a variety of doses. The tolerable upper limit, or safe upper limit, is 10,000 IU. For any dose close to that amount, a doctor should help you determine the amount to take. Most multivitamins contain the recommended dietary allowance (RDA) for vitamin A (see "How do we take vitamin A?").
Unlike vitamin A, beta-carotene does not build up in the body. However, there is some evidence that high doses of beta-carotene can carry some risk. Talk to your doctor before taking more than the recommended amount.
Vitamin A is absorbed along with fat in the diet. Take it with food.
Studies often use high doses of vitamin A. However, such high doses can be toxic. A health care provider should monitor any high-dose therapy (more than 10,000 IU for an adult, or above the recommended daily allowance for a child).
Daily dietary intakes for vitamin A are:
Pediatric
Infants birth - 6 months: 400 mcg
Infants 7 - 12 months: 500 mcg
Children 1 - 3 years: 300 mcg
Children 4 - 8 years: 400 mcg
Children 9 - 13 years: 600 mcg
Boys 14 - 18 years: 900 mcg
Girls 14 - 18 years: 700 mcg
Adult
Men 19 years and older: 900 mcg
Women 19 years and older: 700 mcg
Pregnant women 14 - 18 years: 750 mcg
Pregnant women 19 years and older: 770 mcg
Breastfeeding women 14 - 18 years: 1,200 mcg
Breastfeeding women 19 years and older: 1,300 mcg
Vitamin A dosage is most commonly expressed in units, but dosage in micrograms is sometimes used.
Eating 5 servings of fruits and vegetables per day provides about 50% to 65% of the adult RDA for vitamin A.
Taking too much vitamin A when you are pregnant can cause serious birth defects. Because all prenatal vitamins contain some vitamin A, you shouldn't take a separate vitamin A supplement.
Synthetic vitamin A can cause birth defects. Women who are pregnant or trying to become pregnant shouldn't take this form of vitamin A.
Too much vitamin A is toxic and can cause liver failure, even death. Symptoms of vitamin A toxicity include lasting headache, fatigue, muscle and joint pain, dry skin and lips, dry or irritated eyes, nausea or diarrhea, and hair loss. Vitamin A from foods is considered safe, but you can get too much from supplements. For adults 19 and older, the tolerable upper limit for vitamin A is 10,000 IU per day. Talk to your doctor before taking any dose close to that amount.
Some scientific research suggests that higher doses might increase the risk of osteoporosis and hip fracture, particularly in older people. Adults who eat low-fat dairy products, which are fortified with vitamin A, and a lot of fruits and vegetables usually don't need vitamin A supplements or multivitamins that contain vitamin A.
Long-term use of large amounts of vitamin A might cause serious side effects including fatigue, irritability, mental changes, anorexia, stomach discomfort, nausea, vomiting, mild fever, excessive sweating, and many other side effects. In women who have passed menopause, taking too much vitamin A can increase the risk of osteoporosis and hip fracture.
There is growing concern that taking high doses of antioxidant supplements such as vitamin A might do more harm than good. Some research shows that taking high doses of vitamin A supplements might increase the chance of death from all causes and possibly other serious side effects.
Vitamin A is likely safe for children when taken in the recommended amounts. When amounts greater than those recommended are taken, side effects can include irritability, sleepiness, vomiting, diarrhea, loss of consciousness, headache, vision problems, peeling skin, increased risk of pneumonia and diarrhea, and other problems. The maximum amounts of vitamin A that are safe for children are based on age:
Less than 2000 units/day in children up to 3 years old.
Less than 3000 units/day in children ages 4 to 8 years old.
Less than 5700 units/day in children ages 9 to 13 years old.
Less than 9300 units/day in children ages 14 to 18 years old.
Vitamin A is LIKELY SAFE for pregnant or breast-feeding women when taken in recommended amounts of less than 10,000 units per day. Larger amounts are POSSIBLY UNSAFE. Vitamin A can cause birth defects. It's especially important for pregnant women to monitor their intake of vitamin A from all sources during the first three months of pregnancy. Forms of vitamin A are found in several foods including animal products, primarily liver, some fortified breakfast cereals, and dietary supplements.
People who have liver disease or diabetes should not take vitamin A supplements without their doctor's supervision.
Smokers and people who drink heavy amounts of alcohol should not take beta-carotene supplements. Drinking alcohol may increase vitamin A's potentially harmful effects on the liver.
Both vitamin A and beta-carotene may increase triglycerides, which are fats in the blood. They may even increase risk of death from heart disease, particularly in smokers.
Vitamin A is found in many different types of vitamin formulas. Supplements that say "wellness formula," "immune system formula," "cold formula," "eye health formula," "healthy skin formula," or "acne formula," all tend to contain vitamin A. If you take a variety of different formulas, you could be at risk for too much vitamin A.
If you take large doses of vitamin A, you may want to avoid the food carob. It increases the amount of vitamin A available in your body.
The following reviews have been selected:
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11 of 11 people found the following review helpful:
5.0 out of 5 stars Hello clear skin!, April 6, 2011
By
Ian Biscaldi "Ianster" (SoCal)
I've suffered from some bad breakouts and acne for a long time now, on and off... Anyway, like many others in this terrible world we live in, I tried absolutely everything for my face, washing it all the time, creams, soaps, acids. Up until now nothing really worked all that well, some might have helped a bit, and others made it worse. But then I had an epiphany! after reading an article online about how apricots were good for your skin because of all the vitamin A, i thought, why don't i just go directly to the vitamin and start taking it and see what happens! Well thats exactly what i did, and let me tell you, this is apparently the only thing I needed all along! After 2 days my skin was cleared up, and I've had no breakouts in about 2 weeks! Greatest feeling in the world and I owe it all to this product. Listened people, if you have terrible skin like me, it may just be vitamin A deficiency so try this out... After all the wasted years..
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10 of 12 people found the following review helpful:
5.0 out of 5 stars good if taken when directed, April 2, 2010
By
D. FUENTES
After taking this I've noticed a difference in my skin improving. I've had fewer break outs and has been great for my vision as well. When at the range and focusing on the 300 meter target, it hasn't been as blury. It was always hard to focus in on, up to this point. That was after taking this product for about 3 months.
If you aren't taking this as directed by a doctor, then at least look up the facts from a credible source. One thing that I've noticed is that when I take this before going to bed, I have very vivid dreams. Almost to the point of being lucid. That might be a common side effect.
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36 of 37 people found the following review helpful:
5.0 out of 5 stars Awesome!, December 14, 2009
By
AIM (Illinois)
I used perscription retinol for a long time, it's such a rip off. Besides the 40$ you pay at the pharmacy counter, your dermatologist gets you by making you come in for a 100$ visit for a refill. Really, is that necessary? I decided to try this instead of going in for another "visit".
Wow! It's only been four days, but my face is soft, smooth and glowing! I was skeptical because of the palm oil, since I am prone to break outs, but so far so good! And you only need to use a tiny bit. I have also noticed less surface oil. Great stuff. And how about that price??? :)
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52 of 57 people found the following review helpful:
5.0 out of 5 stars Transformed my skin, July 25, 2009
By
Sara E. Hamblin "Amazonian" (Colorado Springs, CO United States)
This is my first review. I am buying this for the second time because it totally transformed my skin. I used to get breakouts on my chin area, and have rough skin on my cheeks and forehead with red blotches. This has totally changed my skin into even toned, soft and blemish free (occasionally with hormones one will break through but nothing like before). It is way cheaper than other retinol creams, and works great. I highly recommend it - it only took like a week for me to notice a real change, and after a few weeks I am amazed.
The title says 200k iu but it's actually 100k -still great.
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7 of 7 people found the following review helpful:
5.0 out of 5 stars Great Product, May 03, 2009
By
Shirley (Missouri)
I have never been able to tolerate the Beta Carotene so I was happy to find this Vitamin A, from fish oil. What has amazed me is my skin texture. I am 66 years old and have had dry skin for years. I've only been using this product for 3 weeks and my skin is noticeably smoother. I first noticed my hands and feet had improved 100%. My eyes are moist and very clear and they no longer itch just in the short time I have been using this vitamin. There are so many benefits to this form of vitamin A; I will defiantly continue to use it. I'd give it ten stars if it were possible. Shirley
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