Why Is Vitamin A Important for Your Health?
Deficiency of Vitamin A Causes
Vitamins form an integral part of our diet and help us with normal body growth. The derivation of the word vitamin is from Latin ‘vita’ meaning life and ‘amine’, which means amine of life. If we lack vitamins, we are likely to suffer health issues as a result of vitamin deficiency also known as hypovitaminosis. For example, vitamin A deficiency symptoms are dry and rough skin; dry and inflamed eyes, eyelids and surrounding tissues; throat and chest infection; night blindness; and stunted or delayed growth. The deficiency of vitamin A causes these problems, and they can be resolved by adding a sufficient amount of the vitamin in the affected person’s diet. Hypovitaminosis is caused by a general lack of food or an unbalanced diet in which the food that is the source of the vitamin is lacking in quantity.
What are Vitamins?
Vitamins are the essential micronutrients needed by an organism for the proper functioning of bodily activities like metabolism and development. Most vitamins are not synthesised in an organism; therefore, it has to rely on the supply of vitamins from its diet. However, vitamin K is the exceptional vitamin which is synthesised in the human body, i.e., in the small intestines.
A More Detailed View of Vitamin A
Vitamin A is one of the most essential nutrients needed by our body. It helps us with proper vision. It forms a vital role in the production of certain pigments that are vital for the optimum functioning of the retina. The most important sources of vitamin A are nuts, fish, eggs, liver, fortified margarine, beet greens, milk and milk products like cheese and butter, green leafy vegetables, mangoes, watermelon, banana, pumpkin, carrots and potatoes.
Causes of Vitamin A Deficiency
Vitamin A deficiency is caused by the lack of vitamin A. There could be a number of reasons for vitamin A deficiency. However, the general lack of food and overall deficiency of vitamins and nutrients are associated with Vitamin A hypovitaminosis. However, less intake of animal sources of food like meat and dairy products and less consumption of green leafy vegetables and fruits are also some known causes. As an estimation, 1/3 children under five years of age suffer from the deficiency of Vitamin A globally; as a result, approximately 670,000 children below five die every year.
Effects of Vitamin A Deficiency
Due to the severe lack or deficiency of vitamin A, one can face many physiological problems. The problems are as follows:
(1) Dry Eyes- Vitamin A form the part of creation and repair of skin cells, this may cause an ophthalmological condition like dry eyes or xerophthalmia which is characterised by extremely dry eyes which can lead to the inability to produce tears; the problem may worsen due to eczema.
(2) Diminished Vision and Night Blindness- Due to the lack of vitamin A, and lowering in the pigmentation of the eyes, the affected person may face retinal problems like impaired vision especially in lower light conditions or night blindness.
(3) Infertility- Due to the deficiency of vitamin A, both men and women can experience an impact on their ability to reproduce. The reason behind this is that vitamin A is needed for the development of babies. It also functions as an antioxidant required by men with diminished fertility caused by oxidative stress in the body.
(4) Stunted or Delayed Growth- Vitamin A also helps in the growth and development of the body; hence, its deficiency can lead to stunted or delayed growth in children.
Vitamin A Deficiency Treatment
The best way to treat vitamin A deficiency is by including foodstuffs rich in vitamin A in the diet. However, in an extreme situation, supplementing the diet with vitamin A pills is the best method of faster recovery. In a case like dryness of the eyes, eye drops are recommended during the process of recovery. Also, if the dryness of the eyes has caused infections like eczema, then taking care of the infection is the necessary secondary treatment. For children who have a stunted or delayed growth, along with the supplement of vitamin A, other nutrients vital for the growth like calcium, proteins, and other vitamins can help them reach the previously retarded growth faster.
FAQs on Vitamin A Deficiency: Key Facts, Risks, and Prevention
1. What is Vitamin A, and why is it essential for the human body?
Vitamin A is a group of fat-soluble compounds, including retinol, retinal, and retinyl esters, that are vital for numerous bodily functions. Its importance lies in its role in maintaining healthy vision, particularly in low light (preventing night blindness), supporting the immune system, ensuring normal growth and development in children, and keeping the skin and epithelial tissues healthy.
2. What are the main causes of Vitamin A deficiency?
The primary cause of Vitamin A deficiency is an inadequate dietary intake of foods rich in Vitamin A over a prolonged period. Other contributing factors include:
Malabsorption syndromes, where the body cannot properly absorb fats and, consequently, fat-soluble vitamins like Vitamin A.
Chronic diseases of the liver or pancreas, which interfere with vitamin storage and absorption.
High-risk life stages with increased nutritional demands, such as infancy, childhood, pregnancy, and lactation, if not met with sufficient intake.
3. What are the most common symptoms of Vitamin A deficiency?
The earliest and most specific symptom of Vitamin A deficiency is night blindness (nyctalopia), which is the inability to see well in dim light. Other common signs include dry, rough skin (follicular hyperkeratosis), dry eyes (xerophthalmia), recurrent infections due to a weakened immune system, and stunted growth in children.
4. Which foods are rich in Vitamin A and can help prevent its deficiency?
Foods rich in Vitamin A can be sourced from both animal and plant-based origins. Key sources include:
Animal Sources (Preformed Vitamin A - Retinol): Liver, fish liver oils, egg yolks, milk, and dairy products.
Plant Sources (Provitamin A - Carotenoids): Orange and yellow fruits and vegetables like carrots, sweet potatoes, pumpkins, and mangoes, as well as dark green leafy vegetables like spinach and kale.
5. What are the specific diseases and eye conditions caused by severe Vitamin A deficiency?
Severe and prolonged Vitamin A deficiency leads to a spectrum of eye conditions collectively known as xerophthalmia. This progressive disease starts with night blindness and can advance to more severe stages, including Bitot's spots (foamy patches on the conjunctiva), corneal xerosis (drying of the cornea), and keratomalacia (softening and ulceration of the cornea), which can ultimately result in permanent blindness.
6. Why is night blindness often the first sign of Vitamin A deficiency?
Night blindness is the first sign because Vitamin A, in its form as retinal, is a crucial component of rhodopsin. Rhodopsin is the light-sensitive pigment found in the rod cells of the eye's retina, which are responsible for vision in low-light conditions. When Vitamin A levels are low, the body cannot produce enough rhodopsin, leading to impaired vision in the dark before other systemic symptoms become apparent.
7. How does Vitamin A deficiency increase the risk of infections?
Vitamin A is often called the 'anti-infective vitamin' because it plays a critical role in maintaining the body's natural defences. It helps maintain the structural and functional integrity of mucosal barriers in the respiratory, gastrointestinal, and urinary tracts, which are the body's first line of defence against pathogens. It also supports the growth and differentiation of immune cells, such as lymphocytes, which are essential for a robust immune response.
8. Can Vitamin A deficiency be fatal, especially in children?
Yes, severe Vitamin A deficiency can be fatal, particularly in young children and pregnant women. The deficiency significantly weakens the immune system, making children highly susceptible to common childhood illnesses like diarrhoea and measles, and increasing the severity and mortality rate of these infections. For pregnant women, deficiency increases the risk of maternal mortality and can lead to poor outcomes for the baby.
9. How is Vitamin A deficiency clinically diagnosed?
Clinical diagnosis begins with a physical examination, focusing on signs like dry eyes (xerophthalmia) and skin changes. A dietary history is also taken to assess intake. For a definitive diagnosis, a blood test is conducted to measure the concentration of serum retinol. Levels below the normal range confirm the deficiency, and the severity can be determined to guide the appropriate treatment and supplementation plan.
10. Is it possible to have too much Vitamin A? What are the risks?
Yes, consuming excessive amounts of preformed Vitamin A (retinol), typically through high-dose supplements, can be toxic. This condition is known as hypervitaminosis A. Symptoms of toxicity can include dizziness, nausea, headaches, skin irritation, and, in severe cases, liver damage and pressure on the brain. It is important to note that toxicity is generally associated with supplements, not with high consumption of carotenoids from plant sources like carrots.
