Vitamin A deficiency

Vitamin A deficiency is a serious health concern that arises when the body does not receive adequate amounts of vitamin A, an essential nutrient required for proper vision, metabolism, cell development, and immune system function. The human body is unable to synthesise vitamin A on its own, making it necessary to obtain this vital nutrient through a balanced diet or supplementation. Vitamin A deficiency can stem from a diet lacking in vitamin A-rich foods or from underlying health conditions that hinder the absorption or storage of this nutrient in the liver.

What is Vitamin A Deficiency?

Vitamin A deficiency, also called hypovitaminosis A, happens when there is not enough vitamin A in your body. Vitamin A is a fat-soluble vitamin that plays a crucial role in many bodily functions, including eye health, immune function, and cell growth. If not diagnosed and treated, a vitamin A deficiency can cause serious health issues.

The symptoms of vitamin A deficiency can manifest in various ways, depending on the severity and duration of the deficiency. Some people may experience only mild symptoms, while others may develop severe and potentially life-threatening complications. The following are a few common visible vitamin A deficiency symptoms:

1. Night Blindness

One of the earliest signs is night blindness, a condition caused by a disorder of the retina that makes it difficult to see in low-light conditions. This occurs because vitamin A is essential for the production of rhodopsin, a pigment necessary for night vision.

2. Xerophthalmia

As the deficiency progresses, the eyes may become dry and thick, leading to a condition called xerophthalmia, which can potentially damage the cornea and retina.

3. Bitot's Spots

Bitot's spots are distinctive lesions on the eye's conjunctiva and appear as triangular, grey, or white patches, often described as having a frothy or foamy surface.

4. Keratomalacia

Keratomalacia is a serious eye condition characterised by the softening and clouding of the cornea. This condition often begins with xerophthalmia, which involves extreme dryness of the eyes and conjunctiva, and can lead to significant ocular complications if not treated promptly.

5. Corneal Ulcers

Corneal ulcers, also known as keratitis, are medical conditions characterised by open sores on the cornea, the transparent part of the eye. These ulcers can lead to vision loss if not treated promptly.

6. Dry and Scaly Skin

Vitamin A deficiency can also cause the skin to become dry, itchy, and scaly, as this nutrient plays a crucial role in maintaining healthy skin.

7. Disease Susceptibility

Vitamin A deficiency can also weaken the immune system, making individuals more susceptible to infections, especially infants and children.

8. Poor Growth and Development

Children with vitamin A deficiency may experience stunted growth and development.

9. Dry Eyes:

When you don't get enough vitamin A, your eyes can become dry and irritated, leading to a condition known as "xerophthalmia." In more severe cases, this can damage the cornea, which is the clear, protective outer layer of the eye. Dry eyes can also result in difficulty blinking, increased sensitivity to light, and discomfort.

10. Infertility and Trouble Conceiving:

Vitamin A is important for reproductive health in both men and women. In women, a deficiency can disrupt the production of hormones needed for ovulation, making it harder to conceive. In men, it can affect sperm production and quality, leading to reduced fertility. Vitamin A is also involved in the development of healthy embryos during pregnancy, so a lack of it may affect the ability to carry a pregnancy to term.

11. Delayed Growth:

Vitamin A helps in the formation of bone and tissue. When children do not get enough vitamin A, they may experience stunted growth or may fail to reach developmental milestones at the expected age. This can be due to a weakened immune system, which makes it harder for the body to fight off infections that could slow growth.

12. Throat and Chest Infections:

Vitamin A is a vital nutrient for maintaining the health of your mucous membranes, which line the throat, lungs, and other parts of the respiratory system. These membranes act as barriers to pathogens, helping to protect the body from infections. When vitamin A levels are low, your body becomes more susceptible to respiratory infections, including throat and chest infections like pneumonia and bronchitis. It can also increase the risk of complications from infections such as the common cold.

13. Poor Wound Healing:

One of the key functions of vitamin A is supporting the body’s ability to repair tissues. This vitamin promotes collagen production and helps cells regenerate, both of which are essential for wound healing. When you have a deficiency in vitamin A, your body may struggle to heal cuts, scrapes, or other injuries. Wounds may take longer to close, and scarring can be more prominent due to delayed tissue repair.

14. Acne and Breakouts:

Vitamin A is often used in treatments for acne due to its ability to regulate skin cell production. It helps prevent the excessive build-up of dead skin cells that can clog pores and lead to breakouts. A deficiency in vitamin A can cause skin issues, including acne, blackheads, and other types of blemishes. Additionally, a lack of vitamin A can make the skin more prone to dryness and irritation, which can worsen existing acne or cause new breakouts.

Vitamin A deficiency happens when your diet doesn’t provide enough of this essential nutrient. It is more common in developing countries where people may not have access to foods rich in vitamin A. Another reason for this deficiency is liver disorders. Since the liver stores most of the body's vitamin A, any problems with the liver can interfere with the storage and use of vitamin A in the body. Primary causes encompass:

1. Dietary Deficiencies

Prolonged consumption of a diet lacking in vitamin A-rich foods such as animal liver, eggs, fortified dairy products, and carotenoid-rich fruits and vegetables (like orange and yellow fruits and dark green leafy vegetables) is a common cause of deficiency.

2. Malabsorption Disorders

Health issues that impair the intestines' ability to absorb fats, including chronic diarrhoea, coeliac disease, cystic fibrosis, pancreatic insufficiency, and bile duct disorders, can hinder vitamin A absorption.

3. Liver Diseases

Hepatic conditions such as cirrhosis can interfere with the storage and metabolism of vitamin A, potentially leading to a deficiency.

4. Protein-energy Malnutrition

Severe deficiencies in protein and calories can hamper the body's ability to store and utilise vitamin A effectively.

5. Surgical Procedures

Operations involving the intestines or pancreas may also negatively impact vitamin A absorption.

Recognising the multifaceted nature of vitamin A deficiency causes is crucial for accurate diagnosis and appropriate treatment.

Certain diseases and conditions can affect your intestines and reduce your ability to absorb fats, which is important for absorbing vitamin A. These conditions include:

• Chronic diarrhoea
• Celiac disease
• Cystic fibrosis
• Certain pancreatic disorders
• Bile duct blockages
• Zinc or iron deficiencies
• Small bowel bypass or bariatric surgery
• Alcohol use disorder
• Intestinal or pancreatic surgeries

Certain populations face a heightened risk of developing vitamin A deficiency due to geographical, age-related, and health factors.

Who's at Risk?

People falling under the following criteria are at risk of developing vitamin A deficiency:

• Geographical Regions: Individuals living in developing countries, particularly in Africa and Southeast Asia, where diets often lack sufficient vitamin A-rich foods, are particularly vulnerable.

• Age Groups: Children under five years old in developing countries face a significant risk of vitamin A deficiency.

• Health Conditions:

  • Those with gastrointestinal diseases like coeliac disease, liver cirrhosis, pancreatic insufficiency, bile duct disorders, and giardiasis.

  • Pregnant and breastfeeding women due to increased daily requirements.

  • Individuals with chronic infections, especially measles, which can rapidly deplete vitamin A levels.

  • People who have undergone abdominal surgeries, including small bowel bypass and bariatric procedures.

Understanding these risk factors is essential for targeted prevention and early intervention strategies to combat vitamin A deficiency.

Left untreated, vitamin A deficiency can lead to a range of serious health complications affecting vision, skin, immune function, and overall well-being.

Vision Problems

One of the earliest signs of vitamin A deficiency is changes in your vision, such as:

• Night Blindness: Difficulty seeing in low light conditions, potentially progressing to complete blindness at night

• Xerophthalmia: Dryness and thickening of the conjunctiva and cornea, which may result in blindness if left untreated

• Keratomalacia: Drying and clouding of the cornea, causing vision loss

• Bitot's Spots: Formation of foamy deposits in the whites of the eyes

• Corneal Ulcers: Open sores on the cornea, which can ultimately result in blindness

Skin Issues

Skin issues arising due to vitamin A deficiency include:

• Dry, rough, and scaly skin and mucous membranes

• Follicular Hyperkeratosis: Excessive keratin buildup around hair follicles, leading to skin thickening and a "goose flesh" appearance

Compromised Immune Function

Vitamin A deficiency can also lead to impaired immune function and the risk of contracting secondary infections.

• Increased susceptibility to infections, particularly measles and diarrhoeal diseases

• Delayed wound healing and impaired recovery from illnesses

Other Complications

Apart from vision problems, skin issues, and an impaired immune system, hypovitaminosis A is also responsible for:

• Impaired growth and development in children

• Increased risk of anaemia

• Potential reproductive issues, including birth defects

Promptly addressing vitamin A deficiency through proper diagnosis, treatment, and preventive measures is crucial to avoid these potentially life-altering complications.

To prevent vitamin A deficiency, the best approach is to eat a balanced diet with plenty of vitamin A-rich foods. You can find vitamin A in the following:

• Green vegetables like leafy greens and broccoli
• Orange and yellow vegetables like carrots, pumpkin, sweet potatoes, and squash
• Orange and yellow fruits like oranges, mangos, cantaloupes, and papayas
• Dairy products
• Liver, beef, and chicken
• Fish, especially salmon
• Eggs
• Foods like cereals, rice, potatoes, wheat, and soybeans that are fortified with vitamin A

If needed, you can also take a vitamin A supplement.

Diagnosing vitamin A deficiency involves a combination of clinical assessment, medical history, and laboratory tests.

• Clinical symptoms suggestive of vitamin A deficiency include night blindness (nyctalopia), dry corneas, keratomalacia, dry, itchy, and scaly skin, and impaired immune function. A history of impaired dark adaptation and the presence of xerophthalmia (dry eyes) are key clinical indicators of vitamin A deficiency.

• The doctor will review the patient's medical history, including any conditions that might affect vitamin A absorption, such as liver disorders, intestinal diseases, and chronic infections.

• Laboratory tests for vitamin A deficiency diagnosis include electroretinography to measure the photoreceptor response in the retina and serum retinol concentration tests. Other tests, such as the relative dose-response test and the modified relative dose-response test, can help assess hepatic vitamin A stores.

Prompt diagnosis is essential for initiating appropriate vitamin A deficiency treatment and preventing severe complications.

To treat vitamin A deficiency, your healthcare provider will give you high doses of vitamin A supplements for several days. Once your symptoms begin to improve, they’ll reduce the dosage. Vitamin A supplements can treat night blindness and help moisturize your eyes. However, vision loss caused by scarring from corneal ulcers cannot be reversed.

Infants should not take high doses of vitamin A because it can be toxic for them. However, children can be treated with vitamin A supplements, and your child’s doctor will determine the right amount for their age.

Your healthcare provider can also help you plan a healthy diet that includes vitamin A-rich foods. If your retinol levels are already high (over 30 mcg/dL), taking more vitamin A will not help and could be harmful. In this case, simply make sure you are eating enough vitamin A-rich foods to maintain your levels.

• Vitamin A deficiency is a serious condition that can lead to various health issues, including xerophthalmia, night blindness, increased susceptibility to infections, and even death in severe cases.

• The main causes of vitamin A deficiency include inadequate dietary intake of vitamin A-rich foods, malabsorption disorders, and certain medical conditions that interfere with vitamin A metabolism.

• Symptoms of vitamin A deficiency can vary depending on the severity and duration of the deficiency, with the most common being night blindness, dry eyes, and increased susceptibility to infections.

• Diagnosis of vitamin A deficiency typically involves a combination of clinical assessment, dietary history, and laboratory tests, such as serum retinol levels.

• Treatment involves high doses of vitamin A supplements, with the dosage varying by age and special considerations for pregnant and breastfeeding women.

• Vitamin A deficiency prevention strategies include ensuring adequate intake of vitamin A-rich foods, fortification of staple foods with vitamin A, and supplementation programmes targeting high-risk populations.