Vitamin A is important for vision, immunity and normal growth. It comes in two forms: preformed vitamin A from animal foods and provitamin A carotenoids from plants. Too little causes eye problems, but too much preformed vitamin A can be harmful, especially in pregnancy. This guide covers daily needs, food sources, deficiency, safe limits and interactions, based on the NIH Office of Dietary Supplements consumer fact sheet.
How Much Vitamin A Do You Need Each Day?
The NIH lists these recommended amounts in micrograms of retinol activity equivalents (mcg RAE):
- Children 1 to 3 years: 300 mcg; 4 to 8 years: 400 mcg; 9 to 13 years: 600 mcg
- Teen boys and adult men: 900 mcg
- Teen girls and adult women: 700 mcg
- Pregnant women: 770 mcg (750 mcg for pregnant teens)
- Breastfeeding women: 1,300 mcg (1,200 mcg for breastfeeding teens)
Best Food Sources of Vitamin A
Plant foods supply carotenoids that your body converts to vitamin A.
- Fish such as herring and salmon
- Beef liver and other organ meats, which are high in cholesterol so should be limited
- Spinach, sweet potatoes, carrots, broccoli and winter squash
- Cantaloupe, mangoes and apricots
- Dairy foods, eggs and fortified cereals
Vitamin A Deficiency
Deficiency is rare in the United States. The most common sign is an eye condition called xerophthalmia, which can lead to blindness if untreated. Long-term deficiency also raises the risk of pneumonia, measles and diarrhea and can cause anemia.
- Premature infants
- Infants, young children, and pregnant and breastfeeding women in developing countries
- People with cystic fibrosis
- People with Crohn disease, ulcerative colitis or celiac disease
Upper Limits for Preformed Vitamin A
The upper limits apply to preformed vitamin A from food, drinks and supplements together. They do not apply to people taking vitamin A for medical reasons under a doctor care:
- Children 1 to 3 years: 600 mcg; 4 to 8 years: 900 mcg; 9 to 13 years: 1,700 mcg
- Teens 14 to 18 years: 2,800 mcg
- Adults 19 and older: 3,000 mcg
There are no upper limits for beta-carotene and other provitamin A forms.
Too Much Vitamin A and Pregnancy Safety
Too much preformed vitamin A can cause severe headache, blurred vision, nausea, dizziness, muscle aches and problems with coordination. Severe cases can even lead to coma and death.
If you take too much preformed vitamin A during pregnancy, it can cause birth defects, including abnormal eyes, skull, lungs and heart. If you are or might be pregnant or breastfeeding, you should not take high-dose supplements of preformed vitamin A.
Beta-Carotene Cautions
High intake of beta-carotene can turn the skin yellow-orange, which is harmless. However, smokers, former smokers and people exposed to asbestos who take high-dose beta-carotene supplements have a higher risk of lung cancer and death.
Vitamin A and Medicine Interactions
- Orlistat (used for weight loss) can decrease vitamin A absorption.
- Acitretin and bexarotene are made from vitamin A, and taking them with a vitamin A supplement could cause dangerously high vitamin A levels.
When to See a Doctor
- You have trouble seeing in dim light or other eye changes
- You are pregnant or planning pregnancy and take vitamin A supplements
- You have a digestive condition that affects absorption
- You smoke and are considering beta-carotene supplements
Frequently Asked Questions
How much vitamin A do adults need per day?
Adult men need 900 mcg RAE and adult women need 700 mcg RAE a day, according to the NIH.
Which foods are rich in vitamin A?
Salmon, herring, beef liver, dairy, eggs, and colorful plant foods such as sweet potatoes, carrots, spinach, mangoes and cantaloupe.
Is vitamin A safe in pregnancy?
Normal amounts from food are fine, but high-dose supplements of preformed vitamin A should be avoided because they can cause birth defects.
What is the upper limit for vitamin A?
For adults it is 3,000 mcg a day of preformed vitamin A from all sources. There is no upper limit for beta-carotene.
What is the first sign of vitamin A deficiency?
The most common sign is an eye condition called xerophthalmia, which can lead to blindness if untreated.
Related reading: Vitamin C daily needs and safe limits | Zinc daily needs and safe limits | Omega-3 fatty acids guide
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Medical disclaimer: this article is for general information and does not replace advice from a qualified doctor. Do not start, stop or change any supplement or medicine without medical advice.