What is Vitamine A
There are several forms of vitamin A. Renitol is the name for vitamin A found in animal products such as milk, meat, and eggs. In addition, the body can convert plant carotenes into vitamin A. The most well-known carotenoid is beta-carotene. A medium-sized carrot contains 15 milligrams of beta-carotene, sufficient to meet the daily vitamin A requirement. Vitamin A is necessary for skin development, for healthy eye function, and plays a role in growth and the proper functioning of the immune system.
Functions of Vitamin A
Red blood cells: Vitamin A is involved in the production of new red blood cells.
Bone formation: Vitamin A is essential for growth and fracture repair.
Protein metabolism: Vitamin A plays a role in protein production in the body. In stressful situations, the need for protein increases, and therefore also the need for vitamin A. This vitamin is also important for fat metabolism in the liver.
Growth: Skin, eyes, mucous membranes, lymphatic system, reproductive cells, teeth, and bones. Vitamin A supports and regulates the growth and development of cells involved in these processes.
Skin and mucous membranes: Vitamin A enables healthy cell growth in the skin and walls of the respiratory, digestive, and urinary tracts. It therefore plays an important role in the barrier between the body and the outside world.
Reproduction: Vitamin A plays an important role in the production of the sex hormones testosterone and estrogen. The same applies to sperm quality. A vitamin A deficiency is often associated with female infertility.
Immunity: Healthy skin and mucous membranes form a barrier against pathogenic bacteria, viruses, and parasites. But vitamin A is involved in more processes. The production of antibodies that neutralize invaders is also impossible without vitamin A.
Nervous system: Vitamin A nourishes the nerve cells in the brain, the spinal cord, and the nerve pathways.
Vision: The conversion of light into nerve impulses in the eye, which are then processed in the brain. This is partly made possible by vitamin A. Night vision is so dependent on vitamin A that even a small deficiency can lead to poorer vision at night.
Foods rich in Vitamin A
Vitamin A (retinol) occurs naturally only in natural products like meat, fish, dairy, and eggs. Liver is rich in A. Vitamin A is added to margarine and low-fat margarine. Beta-carotene gives vegetables and fruits their yellow or orange color. Carrots are also rich in beta-carotene, but so are cabbage and dark leafy greens.
Foods with Vitamin A
| Food Item | Quantity | Micrograms |
|---|---|---|
| Liver (beef) | 100 g | 9,000 |
| Egg | Medium | 120 |
| Cheese (cheddar) | 30 g | 102 |
| Butter | 10 g | 60 |
| Whole milk | 1 dl | 30 |
Foods with Beta-carotene
| Food Item | Quantity | Milligrams |
|---|---|---|
| Sweet potato | 1 large | 6.0 |
| Carrot | 1 large | 5.5 |
| Cantaloupe | ½ | 1.5 |
| Spinach | 100 g | 1.5 |
Causes of deficiencies
Alcohol: Regular alcohol consumption negatively affects the absorption and storage of vitamin A.
Diabetes/thyroid disorders: The conversion of plant carotenes into vitamin A is difficult in people with diabetes and thyroid disorders.
Medications: Cholesterol-lowering drugs and laxatives limit vitamin A absorption. Some sleeping pills affect the liver’s stored vitamin A reserves.
Liver disorders: People who do not absorb sufficient fats due to problems with the liver, pancreas, or gallbladder often develop a vitamin A deficiency.
Smoking: Inhaling cigarette smoke (including passive smoking!) and other polluted air leads to the consumption of extra vitamin A.
Stress, inflammation, and surgery: In these situations, extra vitamin A is consumed.
Sun: Especially in people with fair skin, bright sunlight (glare on water, snow) can deplete so much vitamin A in the eyes that deficiencies arise elsewhere in the body.
Applications
Arteriosclerosis: A vitamin A deficiency is associated with arteriosclerosis. Beta-carotene reduces the negative effects of bad LDL cholesterol.
Asthma: Vitamin A can reduce asthma symptoms.
Skin and scalp: Dry skin, dandruff, premature skin aging, and eczema can benefit from vitamin A.
Infections: Inflammations of the skin and mucous membranes, ear infections, bladder infections, as well as the flu, acne, and bronchitis, are shorter and milder with vitamin A.
Stomach ulcers: Vitamin A is important for a healthy stomach lining. A healthy lining protects the stomach wall from strong stomach acids.
Menstruation: Vitamin A can reduce symptoms of heavy bleeding and breast tenderness.
Eye diseases: Vitamin A can reduce problems such as night blindness, blurred vision, and eye infections. The risk of cataracts can also decrease.
Consequences of a disturbed vitamin A balance
- Dry eyes, red eyes, reduced night vision.
- Increased susceptibility to infection.
- Increased risk of kidney stones (due to increased calcium excretion).
- Symptoms of fatigue.
- Growth disorders in children.
- Fertility problems.
- Dry, itchy skin with a rash.
- Dry, split hair and brittle nails.
Daily amount
Recommended daily amount of Vitamin A (micrograms)
| Man | 900 |
| Women | 700 |
