From vision to immunity: Vitamin A’s important functions in your body

Focusing our attention on one nutrient each month, let’s learn about Vitamin A. This vitamin is an essential fat-soluble nutrient that plays a vital role in many bodily functions, including vision, immune function, reproduction, and cellular communication. It exists in two primary forms: preformed vitamin A (retinol and retinyl esters), which is found in animal products, and provitamin A carotenoids (such as beta-carotene), which is found in plant-based foods. Let us understand the role of Vitamin A in our body and how it benefits our health.

Read also: Vitamin D3 Deficiency: Why It Happens and What You Can Do About It

Functions of Vitamin A in human body

1. Vision: Vitamin A is important for maintaining normal vision. Retinal, a form of vitamin A, combines with the protein opsin to form rhodopsin, a molecule essential for color vision and vision in low light. Vitamin A deficiency can lead to night blindness and, in severe cases, complete blindness.
2. Immune System Support: Vitamin A enhances immune function by supporting the production and activity of white blood cells, which protect the body from infection. It also helps maintain the integrity of the skin and mucous membranes, acting as a barrier to pathogens.
3. Cell growth and differentiation: Vitamin A is involved in the regulation of genes that control the growth and differentiation of cells. This function is especially important for maintaining healthy skin, lungs and intestines.
4. Reproductive Health: In both men and women, vitamin A plays an important role in reproduction. In men, it is essential for sperm production, while in women, it aids in healthy fetal development during pregnancy.
5. Skin Health: Vitamin A is essential for skin repair and regeneration. It is often used in dermatology to treat acne, psoriasis and other skin conditions due to its ability to promote healthy cell turnover.

Sources of Vitamin A

• Preformed vitamin A (retinol): Found in animal products such as liver, fish oil, eggs, and dairy products. These forms of vitamin A are easily absorbed and used by the body.
• Provitamin A (carotenoids): Found in plant-based foods, especially colorful fruits and vegetables like carrots, sweet potatoes, spinach and mango. Beta-carotene is the best-known provitamin A, which the body converts to retinol as needed.

Also read:Suffering from Vitamin C deficiency? 5 signs your body needs a boost

A good diet will help avoid vitamin A deficiency. Image Credit: iStock

Effects of Vitamin A Deficiency

Vitamin A deficiency is more common in developing countries and can lead to serious health problems, including:

• Night blindness: One of the early symptoms of vitamin A deficiency, where the eyes struggle to adjust to low light conditions.
• Xerophthalmia: A condition characterized by dry eyes and corneal damage that can potentially lead to blindness if left untreated.
• Weakened immune system: Increased susceptibility to infections such as measles and respiratory infections.
• Growth retardation: In children, vitamin A deficiency can stunt growth and impair development.

Excess Vitamin A (Toxification)

While vitamin A is essential, too much of it can be harmful, especially in supplement form. Excessive intake of preformed vitamin A (retinol) can lead to hypervitaminosis A, causing symptoms such as nausea, dizziness, headache, and in severe cases, liver damage and increased intracranial pressure. Pregnant women should avoid excessive intake of vitamin A, as it can cause birth defects.

Provitamin A carotenoids, such as beta-carotene, are not associated with toxicity, although excessive intake may cause the skin to develop a yellow or orange color (a harmless condition called carotenemia).

While vitamin A deficiency can lead to serious health problems, consuming too much of it can also be harmful. A balanced diet rich in fruits, vegetables, and animal products for non-vegetarians usually provides enough vitamin A for most people without the need for supplementation.