Vitamin A is a fat-soluble vitamin that is stored in the liver and fatty tissue. An adult body may store up to a year’s worth of vitamin A. As the body is not able to produce vitamin A, it must be obtained from food. In animal products, vitamin A occurs as retinoids, and in vegetable products as carotenoids. The liver transforms carotenoids into retinoids.
Vitamin A is important for people’s eyesight as it is needed in the production of photoreceptor cells in the retina. Moreover, vitamin A is important for skin growth, bone formation and foetal development. It also acts as an antioxidant, reducing the amount of infections.
Foods rich in vitamin A in retinoid form include liver, fatty dairy products, eggs ad cooking fats. High concentrations of carotenoids, in turn, can be found in orange and red vegetables, berries, fruit and dark leafy greens.
When should vitamin A levels be measured?
Vitamin A levels may decrease if the absorption of fat from the intestines is disrupted due to an inflammatory gastrointestinal illness (Crohn's disease), for example, or because part of the small intestine has been removed in surgery. Disruptions in liver and pancreatic functions may also affect absorption.
Symptoms indicating a vitamin A deficiency include:
- night blindness
- dry eyes
- dry skin and hair
- small cuts and sores
- damage in the cornea
- recurring infections
The test can also be used to measure excessive intake of vitamin A from nutritional preparations, for example.
What does a vitamin A test measure?
A vitamin A test can be used to examine vitamin A levels in blood.
How to interpret the A-vitamin test result?
Normally, the result is:
- Those aged 13-19: 0.9–2.5 µmol/l
- Those aged ≥20: 1.0–3.0 µmol/l
Please contact your physician or other healthcare professional if you suspect an illness or need help interpreting the results.
The reference values of this examination have changed 11.10.2021. You will find your own result's reference values from My LOUNA in touch with the graph. Read more about defining reference values.
What can cause elevated A-vitamin values?
Elevated vitamin A values usually mean that the person is receiving too much vitamin A from vitamin preparations.
What can cause decreased A-vitamin values?
In the Western world, vitamin A deficiency is extremely rare. Vitamin A deficiency primarily occurs in individuals suffering from malnutrition, chronic diarrhoea or malabsorption (coeliac disease, cystic fibrosis or chronic pancreatitis). Decreased vitamin A values occur in elderly people and individuals suffering from alcoholism, liver disease and bile duct disorders. A surgery of the intestines or pancreas may result in vitamin A deficiency.
SYNLAB test list: Vitamin A, from serum, after fasting (1113 fS-A-vit) https://www.yml.fi/tuotekuvaus_show.php?tuotenro=1
Lab Tests Online: A-vitamin https://labtestsonline.org/tests/vitamin-a
Finnish Food Authority: Consumption of liver and liver-based foods https://www.ruokavirasto.fi/en/private-persons/information-on-food/instructions-for-safe-use-of-foodstuffs/safe-use-of-foodstuffs/consumption-of-liver-and-liver-based-foods/
Fasting is not required
This examination does not require fasting