Vitamin A – properties, sources, deficiencies and effects of excess

What is vitamin A?

Vitamin A It's a fat-soluble vitamin that's crucial for healthy skin, proper vision, and immune system function. It comes in two main forms:

• Retinol (active form, present in animal products),

• Beta-carotene (provitamin A, present in plant products – converted into retinol in the body).

Why is vitamin A important?

1. Eye health

Vitamin A supports the production of rhodopsin, a protein essential for night vision. Its deficiency can lead to night blindness.

2. Skin protection

It has anti-aging properties, supports the regeneration of the epidermis and prevents excessive keratinization.

3. Immune system

Increases resistance to infections, supports the functioning of mucous membranes as the first line of defense.

4. Growth and development

Vitamin A plays a role in normal cell growth and fetal development during pregnancy.

Natural sources of vitamin A

Animal products (retinol):

• Liver (beef, poultry)

• Eggs

• Milk and dairy products

• Butter

Plant products (beta-carotene):

• Carrot

• Sweet potatoes

• Pumpkin

• Kale

• Spinach

• Red pepper

• Apricots

Daily requirement for vitamin A

Recommended Daily Allowance (RDA):

RAE = retinol activity equivalent

Symptoms of vitamin A deficiency

• Night vision disturbances

• Dry eyes (xerophthalmia)

• Dry, flaky skin

• Weakened immunity

• Delayed growth in children

Excess vitamin A – can it be harmful?

Yes, excess retinol (especially from supplements) can be toxic.

Symptoms of hypervitaminosis A:

• Headaches

• Nausea

• Skin irritation

• Increased risk of birth defects (during pregnancy)

• Liver damage

⚠️ Note: Beta-carotene is not toxic in large amounts, but it may cause yellowing of the skin (carotenoderma).

Vitamin A supplementation – when is it worth it?

Supplementation is considered when:

• confirmed deficiency,

• fat absorption disorders,

• liver diseases,

• elimination diets (e.g. vegan).

Always consult your doctor or dietitian before supplementing.

Frequently Asked Questions (FAQ)

Does vitamin A help with acne?

Yes, retinoids (vitamin A derivatives) are used to treat acne, both topically and orally – e.g., isotretinoin.

Can you overdose on vitamin A from your diet?

This is difficult to achieve by eating natural foods. The risks mainly come from supplements and excessive liver consumption.

What vitamins work with vitamin A?

It works synergistically with vitamin E, D and zinc – improving its absorption and stability.

Summary

Vitamin A is a key dietary nutrient, essential for healthy eyes, skin, and the immune system. Both deficiency and excess can have serious health consequences. Maintain a balanced diet rich in natural sources of vitamin A, and consider supplementation as a last resort.