Retinol (Vitamin A)
Vitamin A is a fat-soluble vitamin that is stored in the liver. Retinol (Vitamin A) is used for Roles in the body, Who may need extra vitamin A and Measles in high-risk children in low-income countries.
Also called: Vita Pos (New Zealand)
Pronunciation: pronunciation varies by local usage.
- Generic name
- retinol
- Drug class
- Fat-soluble vitamin; preformed vitamin A
- Form
- Not established by the supplied sources. The sources state that vitamin A is available in dietary supplements, most often as retinyl acetate or retinyl palmitate (preformed vitamin A), beta-carotene (provitamin A), or a combination of preformed and provitamin A.
- Route
- Oral (dietary and supplement); retinol is also present in some skin creams applied to the skin
- Legal status
- Dietary supplement. Dietary supplements are not approved by the US FDA for safety or effectiveness before sale. Retinol is also present in some skin creams and fortified foods.
Availability and supply rules vary by country
Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand
Australia: Vitamin A supplements · Full directory
What retinol is and how it works
Vitamin A is a fat-soluble vitamin that is stored in the liver. Vitamin A is also known as retinol because it produces the pigments in the retina of the eye. It is found in two forms in food: retinol, a preformed active form found in animal liver, whole milk, and some fortified foods; and provitamin A carotenoids, plant pigments that the body converts into vitamin A, the most common being beta-carotene. Vitamin A is also available in dietary supplements, most often as retinyl acetate or retinyl palmitate (preformed vitamin A), beta-carotene (provitamin A), or a combination of preformed and provitamin A. Vitamin A plays a role in vision, bone growth, reproduction, cell functions, and the immune system, and helps form and maintain healthy teeth, skeletal and soft tissue, mucus membranes, and skin. (1) (2)
Vitamin A deficiency is very rare in the United States. Recommendations for vitamin A intake are provided as Dietary Reference Intakes (DRIs) that vary by age and sex. The best way to get the daily requirement of important vitamins is to eat a wide variety of fruits, vegetables, fortified dairy foods, legumes (dried beans), lentils, and whole grains. Taking too much vitamin A can cause serious illness. The supplied sources advise checking with your health care provider to see if you need to take vitamin A supplements.
Mechanism of action: how retinol works
Vitamin A is a fat-soluble vitamin that is stored in the liver. It is also known as retinol because it produces the pigments in the retina of the eye. It occurs as preformed vitamin A from animal products and as provitamin A carotenoids from plant foods; the body converts carotenoids into vitamin A, and beta-carotene is an antioxidant that protects cells from damage caused by substances called free radicals. The supplied sources do not provide further pharmacokinetic detail. (1) (2)
What is Retinol used for?
Roles in the body
Vitamin A plays a role in vision, bone growth, reproduction, cell functions, and the immune system. It helps form and maintain healthy teeth, skeletal and soft tissue, mucus membranes, and skin, and promotes good eyesight, especially in low light. It also has a role in healthy pregnancy and breastfeeding. (1) (2)
Who may need extra vitamin A
The supplied sources state that vegetarians, young children, and alcoholics may need extra vitamin A, and that you might also need more if you have certain conditions, such as liver diseases, cystic fibrosis, and Crohn's disease. Check with your health care provider to see if you need to take vitamin A supplements. (2)
Measles in high-risk children in low-income countries
Some research suggests that taking vitamin A may help reduce the risk of measles, but not death from measles, in children in low-income countries who are at high risk for vitamin A deficiency. The same source states that vitamin A deficiency is very rare in the United States and that it is not recommended to take vitamin A to prevent measles. (1)
Cancer and cardiovascular disease prevention
The current evidence does not support the idea that antioxidant supplements can prevent cancer, and the current evidence does not support the idea that antioxidant supplements can prevent cardiovascular disease. In 2022, the U.S. Preventive Services Task Force recommended against the use of beta-carotene or vitamin E supplements for cancer prevention and for prevention of cardiovascular disease, and concluded that the evidence is insufficient to make recommendations about supplements of other single nutrients or pairs of nutrients. The Task Force's recommendation against the use of beta-carotene for cancer prevention is based on studies involving more than 90,000 people, which showed that the harms of beta-carotene outweigh its benefits. (3)
Eye diseases associated with aging (macular degeneration and cataracts)
A 2012 review of 9 high-quality studies (117,272 participants) found no evidence of an effect of antioxidant supplements (vitamin E, vitamin C, beta-carotene) on the occurrence or progression of cataracts. A 2017 review of 5 studies (76,756 participants) did not find any significant benefit of vitamin E, vitamin C, or beta-carotene supplementation in preventing or delaying the onset of age-related macular degeneration (AMD). For people who already have AMD, supplements containing a combination of antioxidants and zinc may slow the progression of the disease. (3)
Cognitive function and dementia
A 2018 review of 8 studies of antioxidant supplements (about 47,000 participants aged 40 or older at the beginning of the studies) found low-certainty evidence of better overall cognitive function after taking beta-carotene for 18 years and after taking vitamin C for 5 to 10 years, but no effects were seen after shorter periods of supplementation or after taking vitamin E; the effects seen were small. Another 2018 review in people with mild cognitive impairment found that high-dose vitamin E for 3 years did not have a significant effect on progression to dementia in one study (516 participants), and in another study of combined vitamin E and C supplementation (256 participants) the evidence was too low in quality for any conclusions to be reached. (3)
Before taking retinol
Do not take / not appropriate for
- It is not recommended to take vitamin A to prevent measles. The supplied sources also state that vitamin A deficiency is very rare in the United States. (measles prevention) (1)
- The 2022 U.S. Preventive Services Task Force recommended against the use of beta-carotene supplements for cancer prevention and for prevention of cardiovascular disease, based on studies showing the harms outweigh the benefits. This applies to beta-carotene, a provitamin A carotenoid, rather than to preformed retinol; the supplied sources do not state a comparable recommendation for preformed vitamin A. (beta-carotene supplements for cancer or cardiovascular disease prevention) (3)
Tell your clinician about
- Check with your health care provider to see if you need to take vitamin A supplements.
- Whether you are vegetarian, a young child, or an alcoholic, as these groups may need extra vitamin A according to the supplied sources.
- Whether you have certain conditions, such as liver diseases, cystic fibrosis, and Crohn's disease, which may mean you need more vitamin A.
- Whether you are pregnant or breastfeeding, because large doses of vitamin A in pregnant women can also cause birth defects, and because reference intakes differ during pregnancy and breastfeeding.
- Whether you smoke or have had occupational exposure to asbestos, and whether you use beta-carotene supplements, because high doses of beta-carotene may increase the risk of lung cancer and the risk of death from cardiovascular disease, with the strongest evidence in people at high risk (smokers and people with occupational exposure to asbestos).
- Whether you have accidental access to, or might swallow, products that contain vitamin A, such as skin cream with retinol in it, because swallowing products that contain vitamin A can also cause vitamin A poisoning. Babies and children are more sensitive to vitamin A and can become sick after taking smaller doses of it.
Retinol dosage and how to take it
- The supplied sources do not provide a supplement dosing schedule for retinol. Dietary intake recommendations are provided as Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board at the National Academies of Sciences, Engineering, and Medicine, which vary by age and sex.
- The best way to get the daily requirement of important vitamins is to eat a wide variety of fruits, vegetables, fortified dairy foods, legumes (dried beans), lentils, and whole grains.
- Check with your health care provider to see if you need to take vitamin A supplements.
- Absorption of vegetable sources of beta-carotene is improved if these sources are eaten with a small amount of fat; vegetable sources of beta-carotene are fat- and cholesterol-free.
- Foods with the highest levels of vitamin A include beef liver and other organ meats (these are high in saturated fat and cholesterol, so limit the amount you eat), some types of fish such as herring and salmon and cod fish oil, eggs, dairy products such as cheese and fortified milk (choose non-fat and low-fat dairy options), fortified breakfast cereals, orange and yellow vegetables and fruits such as carrots, sweet potatoes, mangos, and cantaloupe, and broccoli, spinach, and most dark green, leafy vegetables.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3)
Missed dose
Not established by the supplied sources. These sources do not provide a supplement dosing schedule or missed-dose instructions for retinol; ask your health care provider or pharmacist for advice.
Overdose
If you get too much vitamin A, you can become sick. If you get more vitamin A than you need, it can build up in the body and cause serious health problems. Acute vitamin A poisoning most often occurs when an adult takes several hundred thousand IUs of vitamin A. Chronic vitamin A poisoning may occur in adults who regularly take more than 33,000 IU a day. Babies and children are more sensitive to vitamin A: they can become sick after taking smaller doses of it. Swallowing products that contain vitamin A, such as skin cream with retinol in it, can also cause vitamin A poisoning. Large amounts of beta-carotene will not make you seriously ill, but high amounts can turn the skin yellow or orange, which returns to normal once you reduce your intake of beta-carotene. The supplied sources do not provide overdose management instructions; seek advice from a health care provider or poison information service if an excess intake or accidental swallowing may have occurred. (1)
Retinol side effects
The supplied sources describe risks from both too little and too much vitamin A. Large doses of vitamin A in pregnant women can also cause birth defects. Babies and children are more sensitive to vitamin A.
Yellow or orange skin from high beta-carotene intake
What to notice: High amounts of beta-carotene can turn the skin yellow or orange.
What to do: The skin color will return to normal once you reduce your intake of beta-carotene. Discuss intake with a health care provider. (1)
Too much vitamin A (high intake)
What to notice: If you get too much vitamin A, you can become sick; excess vitamin A can build up in the body and cause serious health problems.
What to do: Contact a health care provider promptly for assessment if excess vitamin A intake is suspected. (1)
Too little vitamin A (deficiency)
What to notice: If you do not get enough vitamin A, you have more risk of eye problems such as reversible night blindness and non-reversible corneal damage known as xerophthalmia; lack of vitamin A can also lead to hyperkeratosis, or dry, scaly skin.
What to do: Contact a health care provider for assessment if these symptoms occur. (1)
Serious warnings
Vitamin A poisoning (acute and chronic high intake) — serious
Symptoms: If you get too much vitamin A, you can become sick. Excess vitamin A can build up in the body and cause serious health problems. Acute vitamin A poisoning most often occurs when an adult takes several hundred thousand IUs of vitamin A. Chronic vitamin A poisoning may occur in adults who regularly take more than 33,000 IU a day. Babies and children are more sensitive and can become sick after taking smaller doses.
Action: The supplied sources do not provide management instructions. Seek advice from a health care provider or poison information service, and let the clinician advise on whether to continue or change any product. (1)
Birth defects from large doses of vitamin A in pregnancy — serious
Symptoms: Large doses of vitamin A in pregnant women can also cause birth defects.
Action: Discuss vitamin A intake, including supplements and products containing retinol, with a health care provider during pregnancy rather than making changes on your own. (1)
Beta-carotene supplements and increased cancer and cardiovascular risk — serious
Symptoms: High doses of one antioxidant, beta-carotene, may increase the risk of lung cancer and may increase the risk of death from cardiovascular disease. Beta-carotene supplementation led to an increase in risk of lung cancer, with the strongest evidence of an increase in risk in people at high risk of this type of cancer (smokers and people with occupational exposure to asbestos), as well as an increased risk of death from cardiovascular disease.
Action: The 2022 U.S. Preventive Services Task Force recommended against the use of beta-carotene supplements for cancer prevention and for prevention of cardiovascular disease. Check with your health care provider about whether you should use beta-carotene supplements. (3)
Accidental swallowing of products containing vitamin A — serious
Symptoms: Swallowing products that contain vitamin A, such as skin cream with retinol in it, can also cause vitamin A poisoning. Babies and children are more sensitive to vitamin A.
Action: Seek advice from a health care provider or poison information service if a product containing vitamin A may have been swallowed. (1)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Combinations of antioxidants | Combinations of antioxidants may have undesirable effects. In one study, a combination of vitamin E, vitamin C, selenium, and beta-carotene reduced the cholesterol-lowering effects of two drugs taken together for this purpose. | Give your health care provider and pharmacist a complete list of supplements and medicines before starting or combining antioxidant supplements. (3) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy and breastfeeding
Large doses of vitamin A in pregnant women can also cause birth defects. The RDA for females aged 19 to 50 is 770 mcg/day during pregnancy and 1,300 mcg/day during breastfeeding, compared with 700 mcg/day for females aged 14 and older generally. Vitamin A also has a role in healthy pregnancy and breastfeeding. Discuss intake with a health care provider. (1)
Children and infants
Babies and children are more sensitive to vitamin A and can become sick after taking smaller doses of it. Dietary reference intakes for vitamin A differ by age: infants 0 to 6 months (AI) 400 mcg/day, 7 to 12 months (AI) 500 mcg/day; children (RDA) 1 to 3 years 300 mcg/day, 4 to 8 years 400 mcg/day, 9 to 13 years 600 mcg/day. Young children are also listed among groups who may need extra vitamin A. (1) (2)
Vegetarians, alcoholics, and people with certain conditions
Vegetarians, young children, and alcoholics may need extra vitamin A. You might also need more if you have certain conditions, such as liver diseases, cystic fibrosis, and Crohn's disease. Check with your health care provider to see if you need to take vitamin A supplements. (2)
Smokers and people with occupational asbestos exposure
The strongest evidence of an increase in lung cancer risk from beta-carotene supplementation is in people at high risk of this type of cancer, namely smokers and people with occupational exposure to asbestos. Beta-carotene also increased lung cancer risk among former smokers in AREDS2. (3)
Monitoring
Before starting
- Check with your health care provider to see if you need to take vitamin A supplements.
- Review whether you belong to a group that may need extra vitamin A, such as vegetarians, young children, or alcoholics, or whether you have conditions such as liver diseases, cystic fibrosis, and Crohn's disease.
- Review pregnancy or breastfeeding status, because large doses of vitamin A in pregnant women can also cause birth defects.
- Review smoking status and occupational asbestos exposure before considering beta-carotene supplements.
- Review all medicines and supplements, because combinations of antioxidants may have undesirable effects.
During treatment
- The supplied sources do not provide monitoring guidance for retinol supplementation. Discuss ongoing intake and any symptoms with your health care provider.
- Watch for signs of excess vitamin A intake (serious illness from too much vitamin A), deficiency (night blindness, xerophthalmia, hyperkeratosis), and, for beta-carotene, yellow or orange skin.
Storage
Not established by the supplied sources. These sources state that vitamin A is a fat-soluble vitamin that is stored in the liver, but they do not provide product storage instructions. Follow the product label and advice from your pharmacist.
Professional information
General nutrient information only, drawn from the supplied US government sources. Dietary supplements are not approved by the US FDA for safety or effectiveness before sale. This page does not provide individualised dosing or treatment advice.
United States
Indication: Dietary vitamin A intake (not a supplement dosing schedule)
Dose summary: Recommendations are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board at the National Academies of Sciences, Engineering, and Medicine, and vary by age and sex. Infants (AI): 0 to 6 months 400 mcg/day; 7 to 12 months 500 mcg/day. Children (RDA): 1 to 3 years 300 mcg/day; 4 to 8 years 400 mcg/day; 9 to 13 years 600 mcg/day. Adolescents and adults (RDA): males age 14 and older 900 mcg/day; females age 14 and older 700 mcg/day (for females aged 19 to 50, 770 mcg/day during pregnancy and 1,300 mcg/day during breastfeeding). RDA is the average daily level of intake that is enough to meet the nutrient needs of nearly all (97% to 98%) healthy people; AI is set when there is not enough scientific research evidence to develop an RDA and is set at a level thought to ensure enough nutrition. The supplied sources do not give a supplement dose for retinol.
Renal context: Not established by the supplied sources. The sources do not provide renal impairment guidance for retinol. (1)
Hepatic guidance
Vitamin A is stored in the liver, and liver diseases are listed among conditions for which you might need more vitamin A; the supplied sources do not provide impairment-specific dosing. Vitamin A can build up in the body and cause serious health problems when intake exceeds need.
Overdose note
Acute vitamin A poisoning most often occurs when an adult takes several hundred thousand IUs of vitamin A. Chronic vitamin A poisoning may occur in adults who regularly take more than 33,000 IU a day. Babies and children are more sensitive and can become sick after smaller doses. Swallowing products containing vitamin A, such as skin cream with retinol in it, can also cause poisoning. Large amounts of beta-carotene will not make you seriously ill but can turn the skin yellow or orange. The supplied sources do not provide management or treatment instructions. (1) (2)
Frequently asked questions
Does vitamin A or beta-carotene prevent cancer or heart disease?
The current evidence does not support the idea that antioxidant supplements can prevent cancer, and the current evidence does not support the idea that antioxidant supplements can prevent cardiovascular disease. In fact, high doses of one antioxidant, beta-carotene, may increase the risk of lung cancer and may increase the risk of death from cardiovascular disease. In 2022, the U.S. Preventive Services Task Force recommended against the use of beta-carotene or vitamin E supplements for cancer prevention and for prevention of cardiovascular disease, and concluded that the evidence is insufficient to make recommendations about supplements of other single nutrients or pairs of nutrients. (3)
Does vitamin A prevent measles?
Some research suggests that taking vitamin A may help reduce the risk of measles, but not death from measles, in children in low-income countries who are at high risk for vitamin A deficiency. Vitamin A deficiency is very rare in the United States, and it is not recommended to take vitamin A to prevent measles. (1)
How much vitamin A do I need each day?
Recommendations are provided in the Dietary Reference Intakes (DRIs) and vary by age and sex. The RDA for males age 14 and older is 900 mcg/day and for females age 14 and older is 700 mcg/day (for females aged 19 to 50, 770 mcg/day during pregnancy and 1,300 mcg/day during breastfeeding). Infants have Adequate Intake (AI) values of 400 mcg/day at 0 to 6 months and 500 mcg/day at 7 to 12 months, and children's RDAs are 300 mcg/day at 1 to 3 years, 400 mcg/day at 4 to 8 years, and 600 mcg/day at 9 to 13 years. The best way to get the daily requirement of important vitamins is to eat a wide variety of fruits, vegetables, fortified dairy foods, legumes (dried beans), lentils, and whole grains. (1)
Can taking too much vitamin A be harmful?
Yes. Taking too much vitamin A can cause serious illness. If you get more vitamin A than you need, it can build up in the body and cause serious health problems, and large doses of vitamin A in pregnant women can also cause birth defects. Acute vitamin A poisoning most often occurs when an adult takes several hundred thousand IUs of vitamin A, and chronic vitamin A poisoning may occur in adults who regularly take more than 33,000 IU a day. Babies and children are more sensitive to vitamin A and can become sick after taking smaller doses of it. Swallowing products that contain vitamin A, such as skin cream with retinol in it, can also cause vitamin A poisoning. (1)
Is beta-carotene the same as retinol?
No. They are different forms of vitamin A. Retinol is the preformed, active form of vitamin A found in animal liver, whole milk, and some fortified foods, while beta-carotene is a provitamin A carotenoid that the body converts into vitamin A. The sources note that large amounts of beta-carotene will not make you seriously ill, though high amounts can turn the skin yellow or orange, whereas too much preformed vitamin A can cause serious health problems. (1)
Do I need a vitamin A supplement?
Check with your health care provider to see if you need to take vitamin A supplements. Vegetarians, young children, and alcoholics may need extra vitamin A, and you might also need more if you have certain conditions, such as liver diseases, cystic fibrosis, and Crohn's disease. Vitamin A deficiency is very rare in the United States. (2) (1)
What is the mechanism of action of retinol?
Vitamin A is a fat-soluble vitamin that is stored in the liver. It is also known as retinol because it produces the pigments in the retina of the eye. It occurs as preformed vitamin A from animal products and as provitamin A carotenoids from plant foods; the body converts carotenoids into vitamin A, and beta-carotene is an antioxidant that protects cells from damage caused by substances called free radicals. The supplied sources do not provide further pharmacokinetic detail. (1) (2)
References
- Vitamin A (Medical Encyclopedia, article 002400)MedlinePlus Medical Encyclopedia, U.S. National Library of Medicine · United States · accessed 2026-10-13 · source 1
- Vitamin A (health topic)MedlinePlus, U.S. National Library of Medicine · United States · accessed 2026-10-13 · source 2
- Antioxidant Supplements: What You Need To KnowNational Center for Complementary and Integrative Health, U.S. National Institutes of Health · United States · dated 2023-07 · accessed 2026-10-13 · source 3
Brand names by country
Single-ingredient retinol names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Vitamin A / Aquasol Arecognised dietary supplement ingredient and FDA approved prescription injectable for deficiency · various OTC IU strengths, 50,000 units/mL (Aquasol A Parenteral) · multiple (supplement) / Casper Pharma LLC (Aquasol A)
United Kingdom
- Vitamin A supplements / prescription vitamin A capsulesrecognised nutrient with official NHS intake and safety guidance · various · multiple
Canada
- Vitamin A (Natural Health Product)Health Canada NNHPD recognised ingredient with dose threshold · up to 10,000 IU/day as an NHP; higher doses regulated as a drug · multiple
Australia
- Vitamin A supplementsrecognised nutrient under joint ANZ NRVs high-dose products TGA-scheduled · various · multiple
New Zealand
- VitA-POSreference source
View brands in additional countries.
European Union
Vitamin A (preformed) supplements/fortified foods