What is Vitamin A deficiency?

 

What is Vitamin A deficiency?

Vitamins are an important part of your diet. They are a group of substances that are consumed in small amounts that help support your overall well-being. Vitamin A specifically is necessary for maintaining healthy eyes, good vision, healthy skin, and helps you fight off infection.

Because the human body can't produce vitamin A on its own, you must incorporate it into your diet in other ways.

When you don't get enough vitamin A in your diet, you may be at risk of developing a vitamin A deficiency. Over time, this can lead to numerous health concerns including vision problems, decreased immunity, and death.

Luckily, you can treat mild forms of vitamin A deficiency without any long-term problems. A severe deficiency is much more common in countries experiencing challenging socioeconomic conditions as well as limited to no access to vitamin A-rich foods.

Signs and symptoms of Vitamin A Deficiency

The following can be the signs and symptoms of Vitamin A Deficiency.

1.     Dryness patches on the skin: Skin cells need Vitamin A to grow and heal themselves. It also aids in reducing inflammation brought on by specific skin problems. Eczema  and other skin conditions may be caused by a lack of Vitamin A in the body. Skin that is dry, itchy, and irritated is also a symptom. 

2.     Itchy eyes: The most well-known effects of Vitamin A Deficiency include eye problems. In severe cases, inadequate Vitamin A intake can result in total blindness or dying corneas, marked by patches known as Bitot's Spots. One of the initial symptoms of Vitamin A Deficiency is dry eyes or the inability to produce tears. Children who eat diets low in Vitamin A, such as those in Southeast Asia, Africa, and India, are particularly at risk of getting dry eyes. According to research, high doses of Vitamin A decreased the rate of dry eyes by 63% in infants and kids who consumed supplements for 16 months. 

3.     Low light or night blindness: Night blindness can result from severe Vitamin A Deficiency. According to several observational studies, there is a high prevalence of night blindness in underdeveloped countries. Health practitioners have attempted to raise Vitamin A levels in patients at risk of night blindness due to the severity of this issue. In one trial, Vitamin A in the form of meals or supplements was given to women who had night blindness. Their condition improved. 

4.     Issues with fertility: Both male and female reproduction and healthy infant development depend on Vitamin A. Vitamin A Deficiency could be one of the causes of your inability to conceive. Infertility can result from a Vitamin A deficit in both men and women. According to research, infertile men may require more antioxidants since their bodies experience more oxidative stress. One of the substances that functions in the body as an antioxidant is Vitamin A. Miscarriages are also linked to Vitamin A Deficiency.

5.     Delayed development: Vitamin A Deficiency in children's diets may cause stunted growth. This is because Vitamin A is essential for the healthy development of the human body. Vitamin A, combined with other nutrients, has been demonstrated in numerous trials to enhance growth. Research in Indonesia involving more than 1,000 kids found that those who were given Vitamin A in high-dose supplements for 4 months saw a growth of 0.39 cm more than kids who received a placebo.

6.     Slow healing of wounds: Low Vitamin A levels may cause slow wound healing following surgery or injury. The reason could be that Vitamin A encourages the production of collagen, which is essential for maintaining healthy skin. According to research, it can assist in repairing the skin locally and orally. Older men who used topical Vitamin A to heal their wounds saw a 50% reduction in the size of their wounds compared to those who didn't.

7.     Chest infections: Infections that frequently recur, especially in the chest or throat, may indicate a Vitamin A deficit. Research findings on Vitamin A supplementation and respiratory tract infections are conflicting. According to a study of children's health, children in Ecuador who received 10,000 IU of Vitamin A per week had less respiratory illness than those who received a placebo. However, a review of research involving kids revealed that taking Vitamin A supplements may raise the risk of chest and throat infections by 8%. According to the studies, people should receive supplements only when they lack certain nutrients. High blood levels of pro Vitamin A may guard against respiratory infections.

 

8.     One of the early signs of vitamin A deficiency is night blindness (nyctalopia).  If you have night blindness, you have trouble seeing well in the dark, but you can see normally if enough light is present. A retinal disorder causes night blindness.

9.     As the vitamin A deficiency worsens, the whites of your eyes and your corneas can become dry and you aren’t able to produce tears (xerophthalmia). Foamy spots called Bitot spots may appear in the whites of your eyes. Open sores on your corneas (corneal ulcers) may appear, or drying or clouding of your corneas (keratomalacia), which can lead to blindness.

What causes vitamin A deficiency?

Vitamin A deficiency occurs when you don’t get enough vitamin A in your diet. While rare in the United States, vitamin A deficiency happens frequently in developing countries around the world. People in impoverished nations don’t get enough food with vitamin A.

Vitamin A deficiency also occurs because of liver disorders. Your liver stores most of your body’s vitamin A, and liver disorders can interfere with vitamin storage.

Diseases and conditions that impair your intestine’s ability to absorb fat can also cause vitamin A deficiency. These conditions can reduce your body’s ability to absorb vitamins such as vitamin A. These conditions include:

• Chronic diarrhea.
• Celiac disease.
• Cystic fibrosis.
• Certain pancreatic disorders.
• Bile duct blockage.
• Zinc or iron deficiency.
• Small bowel bypass or bariatric surgery.  
• Alcohol use disorder.
• Intestine or pancreas surgery.

Who Is At Risk for a Vitamin A Deficiency?

A Vitamin A deficiency is prevalent in Africa and Southeast Asia, where it is estimated that 250 million preschoolers suffer from it due to a lack of carotenoids — yellow, orange, and red organic pigments that are produced by plants and algae — in their diet. Symptoms are made worse by serious infections, particularly measles.

Vitamin A deficiency can also occur in adults with diseases of the gastrointestinal system that interfere with the absorption of Vitamin A. These may include:

• ‌Celiac disease
• Cirrhosis of the liver
• Pancreatic insufficiency
• Bile duct disorder
• Giardiasis
• Duodenal bypass

 

 

Diagnosis of vitamin A deficiency

• Serum retinol levels, clinical evaluation, and response to vitamin A

Ocular findings suggest vitamin A deficiency. Dark adaptation can be impaired in other disorders (eg, zinc deficiency, retinitis pigmentosa, severe refractive errors, cataracts, diabetic retinopathy). If dark adaptation is impaired, rod scotometry and electroretinography are done to determine whether vitamin A deficiency is the cause.

Serum levels of retinol are measured. Normal range is 28 to 86 mcg/dL (1 to 3 mcmol/L). However, levels decrease only after the deficiency is advanced because the liver contains large stores of vitamin A. Also, decreased levels may result from acute infection, which causes retinol-binding protein and transthyretin (also called prealbumin) levels to decrease transiently.

A therapeutic trial of vitamin A may help confirm the diagnosis.

 

 

Treatment of vitamin A deficiency

 

·         Vitamin A

Dietary deficiency of vitamin A is traditionally treated with vitamin A palmitate in oil 60,000 units orally once a day for 2 days, followed by 4500 units orally once a day. If vomiting or malabsorption is present or xerophthalmia is probable, a dose of 50,000 units for infants < 6 months, 100,000 units for infants 6 to 12 months, or 200,000 units for children > 12 months and adults should be given for 2 days, with a third dose at least 2 weeks later. The same doses are recommended for infants and children with complicated measles.

Vitamin A deficiency is a risk factor for severe measles: treatment with vitamin A can shorten the duration of the disorder and may reduce the severity of symptoms and risk of death. It is recommended that all children with measles receive 2 doses of vitamin A (100,000 units for children < 12 months and 200,000 units for those > 12 months) given 24 hours apart (see also  WHO: measles fact sheet  

Infants born of HIV-positive mothers should receive 50,000 units (15,000 RAE) within 48 hours of birth. Prolonged daily administration of large doses, especially to infants, must be avoided because toxicity may result.

For pregnant or breastfeeding women, prophylactic or therapeutic doses should not exceed 10,000 units (3000 RAE)/day to avoid possible damage to the fetus or infant.

Prevention of vitamin A Deficiency

The diet should include dark green leafy vegetables, deep- or bright-colored fruits (eg, papayas, oranges), carrots, and yellow vegetables (eg, squash, pumpkin). Vitamin A–fortified milk and cereals, liver, egg yolks, and fish liver oils are helpful. Carotenoids are absorbed better when consumed with some dietary fat. If milk allergy is suspected in infants, they should be given adequate vitamin A in formula feedings. 

In countries with high rates of food insecurity, prophylactic supplements of vitamin A palmitate in oil 200,000 units (60,000 retinol activity equivalent [RAE]) orally every 6 months are advised for all children between 1 and 5 years of age; infants < 6 months can be given a one-time dose of 50,000 units (15,000 RAE), and those aged 6 to 12 months can be given a one-time dose of 100,000 units (30,000 RAE).