Vitamin A

Vitamin A is one of the fat-soluble vitamins and is only found in foods of animal origin. Its precursors, including the important provitamin A (β-carotene), are found in plant-based foods. β-carotene is one of the so-called carotenoids. It can be converted into vitamin A in the body. Vitamin A is necessary for growth (growth regulation) or the formation and development of cells and various tissues (e.g. skin and mucous membranes). The vitamin also plays an important role in the visual process (especially light and dark vision). β-carotene is an antioxidant and can counteract cell damage caused by so-called free radicals.

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Where is vitamin A contained?
How Much Vitamin A Do We Need?
Too much / too little vitamin A.

Where is vitamin A contained?

A good source of vitamin A is liver. Other foods of animal origin such as fats (e.g. butter), eggs and fish contain small amounts of vitamin A.
A good vegetable source of β-carotene is intensely colored vegetables, especially green vegetables such as spinach, kale, green beans, broccoli and lamb's lettuce, but also carrots and tomatoes.

Note Better usability of carotenoids can generally be achieved by consuming fat or preparing them with fat at the same time (eg adding a little oil to steamed carrots). However, this is not additionally required if the diet is included in a national diet. Exposure to heat and light can lead to vitamin A losses.

How Much Vitamin A Do We Need?

The recommended daily intake for adults (25 to <51 years) per day according to the DA-CH reference values is 0.8 mg (women) and 1.0 mg vitamin A (retinol equivalent). Pregnant women have an increased requirement from the fourth month, the recommended intake is 1.1 mg per day. A daily intake of 1.5 mg is recommended for breastfeeding women. The estimated range for the intake of β-carotene is 2 to 4 mg per day.

You can find out more about all age groups or groups of people as well as gender in the DA-CH reference values.

Note Retinol is another name for vitamin A. Vitamin A (retinol) and carotenoids have different degrees of effectiveness. In order to be able to compare the values, they are converted into so-called equivalents. 1 mg retinol equivalent corresponds to 1 mg vitamin A or 6 mg β-carotene.

For more information, see Covering Your Daily Vitamins.

Too much / too little vitamin A

An overdoseOver a longer period of time, in addition to acute complaints such as headaches, chronic diseases such as skin and skeletal changes as well as liver enlargement and jaundice up to cirrhosis can result. Hypervitaminosis rarely occurs with normal mixed diets. However, caution is advised with nutrient preparations, because a permanently excessive intake of vitamin A can lead to skin changes and liver damage. The vitamin A requirement is increased during pregnancy, but women should generally refrain from consuming liver in the first trimester of pregnancy and only eat it rarely during pregnancy. In smokers, an overdose of β-carotene can damage the health of the lungs, among other things. The intake of nutrient preparations should therefore always be clarified with a doctor.
Vitamin A deficiency is very rare in western industrialized countries. A deficiency can lead to reduced twilight vision or night blindness - if it persists for a long time, it can even lead to blindness. Disorders of the immune system and increased susceptibility to infection are also possible. Serious infections due to vitamin A deficiency, some of which are fatal, occur mainly in developing countries.

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