Vitamin A: Benefits and The Best Sources

Vitamin A, or retinol, plays a crucial role in various bodily functions, including maintaining vision, supporting the immune system, and ensuring proper growth and development in utero. As a fat-soluble vitamin, it can be stored in fat cells for future use.¹

1. Preserves eyesight by preventing night blindness and age-related degeneration through its role in rhodopsin pigment.

2. Maintains a robust immune system by protecting mucous barriers and aiding in the production of white blood cells, reducing susceptibility to infections.

3. Essential for lung development, requiring adequate maternal intake for proper foetal lung growth and postnatal function.

4. Reduces child mortality, showing a significant impact on all-cause mortality in children aged 6 months to 5 years, particularly related to measles and diarrhoeal disease.

5. Promotes reproductive health and normal embryo development during pregnancy, though excess intake can lead to birth defects.

6. Helps manage acne by regulating skin cell growth, and sebum production, and promoting the turnover of skin cells, potentially improving mental health outcomes.²

The Recommended Dietary Allowance (RDA) for men and women is 900 and 700 μg retinol activity equivalents (RAE)/day, respectively.

The Tolerable Upper Intake Level (UL) for adults is set at 3,000 μg/day of preformed vitamin A.³

Overconsumption can lead to toxic levels stored in the body, causing hypervitaminosis. This condition, resulting from animal-based foods or vitamin supplements, may lead to symptoms like nausea, dizziness, headaches, pain, or even death. However, plant-based provitamin A carotenoids, like beta-carotene, pose no similar risk, as they are converted into active vitamin A (retinol) as needed in the body.

Insufficient vitamin A intake can lead to severe symptoms affecting various aspects of health.

1. Visual Impairment: Dry eyes can damage the cornea and retina, leading to night blindness and eventually total blindness in low light.

2. Increased Infections: Vitamin A deficiency weakens the immune system, resulting in more frequent and severe infections, with heightened risks of mortality, especially from diseases like measles and diarrhoea.

3. Skin Problems: Dryness, itching, and flaking of the skin, along with issues affecting hair and scalp, may manifest in those lacking adequate vitamin A.

4. Fertility Challenges: Vitamin A deficiency can cause infertility and difficulties in conceiving, emphasizing its crucial role in reproductive health.

Animal products and select vegetables are excellent natural sources of vitamin A. These include carrot, beef liver, sweet potato, butternut squash, spinach, and dairy products. Consider the cost of vitamin A in different foods when planning a balanced diet.⁴

Prioritise obtaining vitamin A from a varied diet rather than supplements. If choosing supplements, consult your doctor for proper dosage, considering dietary intake.

Note: Various factors impact vitamin A content, including high-temperature cooking, light exposure, air (oxygen-induced destruction prevented by airtight containers), water contact, processing methods (such as canning and freezing), and improper storage leading to age-related decrease in vitamin A content.

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