How does vitamin A help you see at night?
Vitamin A helps you see at night: your eye turns it into rhodopsin, the pigment that catches faint light. It comes from liver, fish, eggs, dairy and orange vegetables, travels through the lymph and is stored mostly in the liver.
Which foods provide the most vitamin A?
Liver is by far the richest. One serving of beef liver alone provides more than 7 days of an adult man's needs (our calculation: 6,582 ÷ 900). Orange vegetables also provide a lot, once beta-carotene is converted (ODS figures, in micrograms of retinol activity equivalents).
| Food | Serving | Vitamin A | Form |
|---|---|---|---|
| Beef liver | 3 oz (85 g), pan-fried | 6 582 µg | retinol |
| Sweet potato | 1 whole, cooked | 1 403 µg | carotenes |
| Cooked spinach | ½ cup | 573 µg | carotenes |
| Raw carrots | ½ cup | 459 µg | carotenes |
| Hard-boiled egg | 1 large | 75 µg | retinol |
| Salmon | 3 oz (85 g), cooked | 59 µg | retinol |
How does it get from the plate to the liver?
It travels with fats. In the gut, the body absorbs 75 to 100% of retinol, but only 10 to 30% of the beta-carotene in food. Gut cells package it into chylomicrons, which pass through the lymph, then the blood, and end up in the liver. A little fat in the meal therefore helps absorption.
Where is it stored, and for how long?
Mainly in the liver, as retinyl esters, in the stellate cells (the often-quoted share, up to 80%, is still to be checked). We do not give a storage duration: no solid source sets a figure that holds for everyone. When the body needs it, the liver releases retinol attached to its transport protein, RBP.
What does vitamin A do?
First, it helps you see: in the rods of the eye, retinal joins a protein to form rhodopsin, which captures faint light. That is why the first sign of a deficiency is poor vision in dim light. It also serves the cornea, the immune system, reproduction and growth: as retinoic acid, it regulates more than 500 genes.
Deficiency is mainly a problem in low-income countries: in 2013, it affected 29% of children aged 6 months to 5 years in 138 low- and middle-income countries.
Page updated on October 30, 2026. Requirements are those of the ODS (United States); they vary a little by country.
Frequently asked questions
Can you take too much vitamin A?
Yes, with preformed vitamin A: the limit is 3,000 µg a day for adults. Prolonged excess can cause dry skin, pain, fatigue and liver damage.
Why be careful during pregnancy?
Above the limit, preformed vitamin A can cause birth defects. Beta-carotene is not known to carry this risk. Before taking a supplement or large amounts of liver, talk to your doctor or midwife.
Do carrots turn you orange?
A lot of carrots can color the skin yellow-orange, especially the palms. This is called carotenodermia: it is not dangerous and goes away when you cut back.
Do carrots help you see in the dark?
They prevent a deficiency, which causes poor vision in dim light. But if your stores are already good, eating more will not make you see better.
Why doesn't 1 µg of vitamin A equal 1 µg of beta-carotene?
Because beta-carotene is poorly absorbed and not always converted: it takes 12 µg in food to get 1 µg of retinol. Requirements are therefore given in equivalents (RAE).
See also
Night vision The route of fats The lymph in motion Vitamin E and oxidation Vitamin K and clotting
Sources
- NIH Office of Dietary Supplements. Vitamin A and Carotenoids, fact sheet for health professionals. ods.od.nih.gov
- Linus Pauling Institute, Oregon State University. Vitamin A. lpi.oregonstate.edu
True or false?
The liver is the main store of vitamin A.
True. It stores it as retinyl esters, mainly in its stellate cells, and releases it as needed (ODS).
Beta-carotene is absorbed as well as retinol.
False. The body absorbs 75 to 100% of retinol, but only 10 to 30% of the beta-carotene in food (ODS).
Poor vision in dim light can be a sign of vitamin A deficiency.
True. It is the first sign: without vitamin A, the eye makes less rhodopsin, the pigment that captures faint light (ODS).
Cite this page
To cite this page in a paper, an article or a presentation:
Metabolive. "How does vitamin A help you see at night?" Updated November 1, 2026. https://metabolive.com/en/everyday/vitamin-a.