Vitamin A Test

Retinol, Retinyl Esters, and Retinals are among the fat-soluble retinoids (chemical compounds) known as Vitamin A. Vitamin A plays a vital role in immune function, reproduction, eyesight, and cellular communication.

Vitamin A is essential for vision because it is a component of Rhodopsin, a protein that absorbs light in the retinal receptors. It helps in night vision by forming part of Rhodopsin, which allows vision under low-light conditions. 

Vitamin A is also essential for the creation and maintenance of the lungs, heart, kidneys, and other organs, as it promotes cell growth and cell differentiation.

Two accessible forms of vitamin A available in the human diet are

1. Preformed Vitamin A (Retinol & its esterified form, Retinyl Ester)

Animal-based foods, including dairy products, fish, and meat, contain preformed vitamin A.

1. Provitamin A Carotenoids

Beta-carotene is the most significant provitamin A carotenoid. Alpha-carotene and beta-cryptoxanthin are the other provitamins A carotenoids. These plant pigments are converted into vitamin A by the body.

The Provitamin A and Preformed Vitamin A must be transformed intracellularly into two to carry out vitamin A’s essential biological functions. The two dynamic forms are Retinal and Retinoic acid.

Vitamin A tests check if individuals are deficient or have excess vitamin A in their blood.

Vitamin A insufficiency is a risk factor for severe measles; vitamin A therapy can minimise the duration of the illness or disease and the severity of symptoms, and the chance of mortality.

Vitamin A deficiency can impair night vision, induce eye damage, and even result in blindness in severe cases. On the other hand, too much vitamin A can be harmful, resulting in various symptoms like headaches, rashes, coarse hair, dry skin, cracked lips, and in rare cases, birth abnormalities.

Overuse of vitamin supplements is the leading cause of vitamin A toxicity. It can, however, happen when the diet contains a significant amount of vitamin A-rich foods, such as beef liver, cod liver oil, carrots, etc.

If a body has difficulties absorbing fats via the digestive tract, it may be deficient in vitamin A. So, a Vitamin A test is preferred. The test may also be advised if an individual has:

• Cystic fibrosis is a chronic lung disease.
• Problems with the pancreas like inflammation (pancreatitis) and swelling or the organ’s inability to produce adequate enzymes (pancreatic insufficiency).
• Coeliac disease, a minor intestinal ailment

Vegans, children under the age of five, and alcoholics may require more Vitamin A. If an individual has specific disorders like cystic fibrosis, Crohn’s disease or liver disease, they may need more vitamin A. Consult the doctor to determine whether you need any vitamin A supplements.

Other Names of Vitamin A Test

• Retinol Test
• Vit A test

What Does Vitamin A Measure, and Who is This Prescribed For?

The Vitamin A test measures the levels of vitamin A in the blood.

The Vitamin A test is indicated in people with the following symptoms of vitamin A deficiency-

• Inflamed or dried eyes
• Teeth or bone problems in young children
• Skin rashes
• Dry skin
• Recurring infections
• Night blindness
• Reduced growth
• The Vitamin A test is indicated in people with the following symptoms of vitamin A toxicity -
• Loss of appetite
• Anaemia
• Increased pressure in the brain (pseudotumor cerebri)
• Liver and spleen enlargement
• Hair loss
• Diarrhoea
• Lack of muscle coordination (ataxia)
• Bone & muscle pain
• Double vision
• Nausea

A Vitamin A test may be prescribed regularly when an individual has an illness linked to nutritional malabsorption, such as

• Diabetes
• Irritable bowel syndrome
• Coeliac disease
• Crohn’s disease, an inflammatory bowel disease type

The results of the Vitamin A blood test are derived from an individual's blood sample.

Test Preparation of Vitamin A Test

The Vitamin A test has got fasting requirements. An individual can fast between 9 to 12 hours. You may also need to avoid iron or health supplements and alcohol consumption before taking the Vitamin A test.

Test Inclusions: What Parameters Are Included?

The Vitamin A test includes only one parameter, the levels of vitamin A in the blood.

How Frequently Should You Take This Test?

• The Vitamin A test is repeated every 3-6 months in case of a deficiency or toxicity. This is to monitor the treatment for your deficiency or toxicity.
• As a part of your routine tests, the Vitamin A test can be repeated annually.

Vitamin A toxicity, Vitamin A deficiency

The ranges for the Vitamin A test are as follows. The ranges will vary during pregnancy and lactation.