Vitamin A

What is Vitamin A?

Vitamin A is also known as retinol and is a fat-soluble vitamin naturally found in many foods. Vitamin A supports the immune system, vision, skin health, and reproduction. It’s also important for the normal function of your organs including your heart and lungs. Vitamin A is found naturally in animal products including dairy, eggs, and offal meats like liver and kidneys^[1]. The body is unable to make vitamin A, so you must get it from your diet.

Vitamin A is especially important for eye health. A low level of vitamin A can lead to night blindness because the eyes aren’t able to make the pigments they need for proper vision. Vitamin A also ensures the eyes are well-lubricated^[2].

The total amount of vitamin A adults aged 19 to 64 need is:

• 700 µg for a man

• 600 µg for a woman

Most people will get all the vitamin A they need from their diet and any excess will be stored for later use.

What are Normal Vitamin A Levels?

The normal range for vitamin A will depend on the testing laboratory, so different labs will have different parameters that are considered normal. The NHS states that a healthy range is between 1.1 and 3.4 umol/L for adults aged 18 and over^[4].

At Forth, our healthy range for vitamin A is as follows:

What Impacts Vitamin A Levels?

Several factors can cause changes to vitamin A levels. Vitamin A deficiency is rare in the UK. Low vitamin A levels are often caused by not getting enough in your diet or:

• coeliac disease

• cystic fibrosis

• chronic pancreatitis

• alcoholism

• liver disease

Symptoms of low vitamin A levels include:

• night blindness

• dry hair, skin, mouth

• broken nails

• frequent infections

• eye sores

• fatigue

• diarrhoea

• bladder infections

• vaginal infections

• respiratory infections

• delayed wound healing

Who is most affected by a vitamin A deficiency?

Vitamin A deficiency is one of the most common deficiencies around the world. It is most common in children and pregnant women. The risk of deficiency is highest during the third trimester when your baby’s development accelerates and their blood volume increases. However, you should be able to get all of the vitamin A you need by eating a healthy, balanced diet^[5].

High vitamin levels are usually a result of taking too many vitamin supplements but it can also occur if you eat too many vitamin-A-rich foods. However, prolonged and excessive vitamin A intake can have dangerous consequences and may affect your liver, bones, central nervous system, and skin^[6].

Symptoms of high vitamin A levels include:

• blurred vision

• headaches

• hair loss

• dry skin

• fatigue

• bone pain^[4]

Large amounts of vitamin A during pregnancy can harm unborn babies. So, if you are pregnant or considering getting pregnant, you should avoid consuming a large amount of vitamin A.

Pregnant women should avoid:

• liver

• liver products e.g. pate

• vitamin A supplements

If you are unsure or need further information about vitamin A during pregnancy, speak to your midwife or GP.

Managing Vitamin A Levels

Several factors can help you manage your vitamin A levels, whether they are high or low.

You can help to boost or maintain your levels within a healthy range by eating vitamin A-rich foods. Vitamin A is found in both plant and animal sources.

Although it is possible to cause toxicity or high vitamin A levels through an excessive consumption of animal-based plant sources, the most common cause is an overconsumption of vitamin A supplements^[8].

To avoid vitamin A toxicity it is important to make sure you are not exceeding your recommended daily allowance. Some of the things you can do to avoid consuming too much vitamin A include:

• checking the ingredients of your medicines and supplements

• limiting your consumption of liver and liver products to once per week

• being aware of the symptoms of high vitamin A levels

Written by Leanne Edermaniger

Based in the UK, Leanne specialises in writing about health, medicine, nutrition, and fitness.

She has over 5 years of experience in writing about health and lifestyle and has a BSc (hons) Biomedical Science and an MSc Science, Communication and Society.