Background information
The health benefits of red fruit and veg
by Anna Sandner
Vitamin A supports healthy skin and strong bones
2-8-2024
Translation: Eva Francis
Vitamin A is crucial for your eyesight, immune system and cell development. Read on to find out which foods contain a lot of vitamin A, how it works in the body and why having too little or too much of it can be a problem.
Our food contains vitamin A in two different forms: as retinol in animal products and as carotenoids in plant-based foods. While the body can use retinol directly, carotenoids have to be converted into active vitamin A first. Retinol equivalents (RAE) is the unit of measurement that’s used to make the effect of the various forms comparable.
The German Nutrition Society recommends a daily intake of 0.8 mg (women) to 1.0 mg (men) RAE for adults. You can easily achieve this by maintaining a balanced diet. This is important because vitamin A fulfils numerous vital functions in the body.
Why your body needs vitamin A
Vitamin A is crucial for your vision, because it’s an important component of the visual pigment rhodopsin, which is responsible for seeing at dusk and in the dark. Without sufficient vitamin A, you might experience night blindness.
Vitamin A is also crucial for a well-functioning immune system. It supports the function of T-cells and B-cells, which play a central role in immune defence.
The fat-soluble vitamin is also extremely important for cell growth and cell differentiation. It regulates gene expression and is therefore essential for the healthy development of cells and tissues. This is why it’s particularly important for children.
Vitamin A also plays a fundamental role in the health of skin and mucous membranes. It promotes the formation and maintenance of healthy epithelial cells that line the skin and mucous membranes.
Last but not least, vitamin A also supports the regulation of bone metabolism and thus contributes to bone health.
The effects of vitamin A deficiency
A vitamin A deficiency can have serious health consequences. One of the first signs is often night blindness – impaired vision in low light conditions. In severe cases, this can lead to xerophthalmia, a disease that causes corneal damage and can even lead to blindness.
A lack of vitamin A also significantly increases the risk of infections, as it weakens the immune system, leaving the body less able to fight infections.
In children, a vitamin A deficiency can lead to growth retardation – impaired development of tissues and organs.
The skin also suffers from a lack of vitamin A. It gets dry and flaky. This isn’t only a cosmetic issue, but also damages the skin’s barrier function and thus increases the risk of skin infections.
Vitamin A-rich foods
Retinol (from animal products) is the active form of vitamin A and can be used directly by the body. Particularly rich sources of retinol are liver, eggs and dairy products. However, liver contains so much vitamin A that excessive consumption can even lead to an overdose.
Plant-based foods contain provitamin A in the form of carotenoids, which the body can convert into active vitamin A. Orange and dark green vegetables and fruits are particularly rich in carotenoids. Carrots, for instance, are known for their high beta-carotene content. Sweet potatoes, kale, spinach, mangoes and apricots are also good sources.
Vitamin A is fat-soluble, meaning the body can absorb it better if it’s combined with oil or fat. Having a salad with carrots and an olive oil dressing, for example, is a great way to optimise your vitamin A intake.
Other important facts about vitamin A
As a fat-soluble vitamin, vitamin A can be stored in the body. This has both advantages and disadvantages. On the one hand, it allows the body to build up reserves. On the other hand, there’s a risk of toxicity if you take too much of it. An excess of vitamin A, especially in the form of retinol from supplements, can lead to symptoms such as headaches, blurred vision and liver damage. This risk doesn’t usually exist with carotenoids from food.
Special care should be taken during pregnancy; both a deficiency and an excess of vitamin A can lead to malformations in the foetus. Pregnant women should therefore discuss their vitamin A intake with their doctor.
Vitamin A can also interact with certain medications and thus influence the effect of some antibiotics – or vitamin A absorption can be impaired by cholesterol-lowering drugs. For this reason, you should always discuss the intake of vitamin A supplements with a doctor.
Find out more about minerals, vitamins and fibre and why they’re essential for your health:
Header image: Tatevosian Yana/Shutterstock
Science editor and biologist. I love animals and am fascinated by plants, their abilities and everything you can do with them. That's why my favourite place is always outside - somewhere in nature, preferably in my wild garden.