Vitamin A

Vitamin A is a fat-soluble vitamin that is crucial for various bodily functions, particularly in maintaining healthy vision, immune function, and skin health. It exists in several forms, including preformed vitamin A (retinol) and provitamin A carotenoids (such as beta-carotene).

Key Function:

Vision:

  • Vital for the formation of rhodopsin, a pigment in the retina that allows for low-light and color vision.

  • Helps prevent night blindness and maintains overall eye health.

Immune Function:

  • Supports the immune system by maintaining the integrity of epithelial tissues (skin and mucous membranes), acting as a barrier to pathogens.

  • Enhances the functioning of immune cells, promoting a stronger immune response.

Skin Health:

  • Promotes healthy skin by supporting cell production and repair.

  • Plays a role in stimulating the production of collagen, helping to maintain skin elasticity.

Cell Growth and Development:

  • Important in cell differentiation and growth, making it crucial for fetal development during pregnancy.

Dietary Sources:

Preformed Vitamin A (Retinol): Found in animal products such as liver, fish, dairy products, and eggs.

  • Provitamin A Carotenoids: Found in plant-based sources such as:

    • Carrots

    • Sweet potatoes

    • Spinach

    • Kale

    • Mangoes

    • Cantaloupe

Deficiency:

Vitamin A deficiency can lead to issues such as night blindness, dry eyes, and increased susceptibility to infections. Severe deficiency can result in more serious health problems, including compromised immune function and skin issues.

Recommended Intake

The recommended dietary allowance (RDA) varies by age and gender, typically around 700 micrograms (mcg) of retinol activity equivalents (RAE) for adult women and 900 mcg for adult men.

Vitamin A is essential for maintaining vision, immune function, and healthy skin. It can be obtained through a balanced diet rich in both animal and plant sources. Understanding its functions and dietary needs can help promote optimal health and prevent deficiencies. Always consult with a healthcare professional before starting any supplementation.