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 wellbeing. 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.

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 infection, particularly measles.

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

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

Signs and Symptoms

Vitamin A is a fat-soluble vitamin that is important for many bodily functions, including proper vision, a strong immune system, reproduction and good skin health.

There are two types of vitamin A found in foods: preformed vitamin A and provitamin A (1Trusted Source).

Preformed vitamin A is also known as retinol and commonly found in meat, fish, eggs and dairy products.

On the other hand, the body converts carotenoids in plant foods, such as red, green, yellow and orange fruits and vegetables, into vitamin A (2Trusted Source).

While deficiency is rare in developed countries, many people in developing countries do not get enough vitamin A.

Those at highest risk of deficiency are pregnant women, breastfeeding mothers, infants and children. Cystic fibrosis and chronic diarrhea may also increase your risk of deficiency.

Here are 8 signs and symptoms of vitamin A deficiency

1. Dry Skin

• Vitamin A is important for the creation and repair of skin cells. It also helps fight inflammation due to certain skin issues (3Trusted Source).
• Not getting enough vitamin A may be to blame for the development of eczema and other skin problems (4Trusted Source).
• Eczema is a condition that causes dry, itchy and inflamed skin. Several clinical studies have shown alitretinoin, a prescription medication with vitamin A activity, to be effective in treating eczema (3Trusted Source, 5, 6Trusted Source).
• In one 12-week study, people with chronic eczema who took 10–40 mg of alitretinoin per day experienced up to a 53% reduction in their symptoms (6Trusted Source).
• Keep in mind that dry skin can have many causes, but chronic vitamin A deficiency may be the reason.

2. Dry Eyes

• Eye problems are some of the most well-known issues related to vitamin A deficiency.
• In extreme cases, not getting enough vitamin A can lead to complete blindness or dying corneas, which are characterized by marks called Bitot’s spots (7Trusted Source, 8Trusted Source).
• Dry eyes, or the inability to produce tears, is one of the first signs of vitamin A deficiency.
• Young children in India, Africa and Southeast Asia who have diets lacking in vitamin A are most at risk of developing dry eyes (9Trusted Source).
• Supplementing with vitamin A can improve this condition.
• One study found that high doses of vitamin A decreased the prevalence of dry eyes by 63% among infants and children who took supplements for 16 months

3. Night Blindness

• Severe vitamin A deficiency can lead to night blindness (11Trusted Source).
• Several observational studies have reported a high prevalence of night blindness in developing nations (12Trusted Source, 13Trusted Source, 14Trusted Source, 15Trusted Source).
• Due to the extent of this problem, health professionals have worked to improve vitamin A levels in people at risk of night blindness.
• In one study, women with night blindness were given vitamin A in the form of food or supplements. Both forms of vitamin A improved the condition. The women’s ability to adapt to darkness increased by over 50% over six weeks of treatment

4. Infertility and Trouble Conceiving

• Vitamin A is necessary for reproduction in both men and women, as well as proper development in babies.
• If you are having trouble getting pregnant, a lack of vitamin A may be one of the reasons why. Vitamin A deficiency can lead to infertility in both men and women.
• Studies show that female rats with vitamin A deficiency have difficulty getting pregnant and may have embryos with birth defects (17).
• Other research suggests that infertile men may have a greater need for antioxidants due to higher levels of oxidative stress in their bodies. Vitamin A is one of the nutrients that acts as an antioxidant in the body (18Trusted So
• Vitamin A deficiency is also related to miscarriages.
• A study that analyzed the blood levels of different nutrients in women who had recurrent miscarriages found that they had low levels of vitamin A 

5. Delayed Growth

• Children who do not get enough vitamin A may experience stunted growth. This is because vitamin A is necessary for the proper development of the human body.
• Several studies have shown that vitamin A supplements, alone or with other nutrients, can improve growth. Most of these studies were conducted in children in developing nations (20Trusted Source, 21Trusted Source, 22Trusted Source, 23Trusted Source).
• In fact, a study in over 1,000 children in Indonesia found that those with vitamin A deficiency who took high-dose supplements over four months grew 0.15 inches (0.39 cm) more than children who took a placebo (20Trusted Source).
• However, a review of studies found that supplementing with vitamin A in combination with other nutrients may have a greater impact on growth than supplementing with vitamin A alone (22Trusted Source).
• For example, children with stunted growth in South Africa who received multiple vitamins and minerals had length-for-age scores that were half a point better than those who received only vitamin A

6. Throat and Chest Infections

• Frequent infections, especially in the throat or chest, may be a sign of vitamin A deficiency.
• Vitamin A supplements may help with respiratory tract infections, but research results are mixed.
• A study in children in Ecuador showed that underweight children who took 10,000 IU of vitamin A per week had fewer respiratory infections than those who received a placebo (24Trusted Source).
• On the other hand, a review of studies in children found that vitamin A supplements may increase the risk of developing throat and chest infections by 8% (25Trusted Source).
• The authors suggested that supplements should only be given to those with true deficiency (25Trusted Source).
• Furthermore, according to one study in elderly people, high blood levels of the provitamin A carotenoid beta-carotene may protect against respiratory infections 

7. Poor Wound Healing

• Wounds that do not heal well after injury or surgery may be linked to low vitamin A levels.
• This is because vitamin A promotes the creation of collagen, an important component of healthy skin. Research suggests that both oral and topical vitamin A can strengthen skin.
• A study in rats found that oral vitamin A improved collagen production. The vitamin had this effect even though the rats were taking steroids, which can inhibit wound healing (27Trusted Source).
• Additional research in rats found that treating skin with topical vitamin A appeared to prevent wounds associated with diabetes (28Trusted Source).
• Research in humans shows similar results. Elderly men who treated wounds with topical vitamin A had a 50% reduction in the size of their wounds, compared to men who did not use the cream 

8. Acne and Breakouts

• Since vitamin A promotes skin development and fights inflammation, it may help prevent or treat acne.
• Multiple studies have linked low vitamin A levels to the presence of acne (30Trusted Source, 31Trusted Source).
• In one study in 200 adults, vitamin A levels in those with acne were over 80 mcg lower than in those without the condition (30Trusted Source).
• Topical and oral vitamin A may treat acne. Research shows that creams containing vitamin A can reduce the number of acne lesions by 50% (32Trusted Source).
• The most well-known form of oral vitamin A used to treat acne is isotretinoin, or Accutane. This medication can be very effective at treating acne but may have a number of side effects, including mood changes and birth defects

Dangers of Too Much Vitamin A

Vitamin A is valuable to overall health. However, too much of it can be dangerous.

Hypervitaminosis A, or vitamin A toxicity, typically results from taking high-dose supplements over long periods of time. People rarely get too much vitamin A from diet alone (34Trusted Source).

Excess vitamin A is stored in the liver and can lead to toxicity and problematic symptoms, such as vision changes, swelling of the bones, dry and rough skin, mouth ulcers and confusion.

Pregnant women should be especially careful not to consume too much vitamin A to prevent possible birth defects.

Always check with your healthcare provider before starting vitamin A supplements.

People with certain health conditions may need a higher amount of vitamin A. However, most healthy adults need 700–900 mcg per day. Women who are nursing need more, while children need less

The Bottom Line

Vitamin A deficiency is prevalent in developing nations but rare in America and other developed nations.

Too little vitamin A can lead to inflamed skin, night blindness, infertility, delayed growth and respiratory infections.

People with wounds and acne may have lower blood levels of vitamin A and benefit from treatment with higher doses of the vitamin.

Vitamin A is found in meat, dairy and eggs, as well as red, orange, yellow and green plant foods. To make sure you get enough vitamin A, eat a variety of these foods.

If you suspect you have a vitamin A deficiency, talk to your doctor or healthcare provider. With the right foods and supplements, fixing a deficiency can be simple

Causes of Vitamin A Deficiency

Vitamin A deficiency is usually caused by

A diet that has been deficient in vitamin A for a long time

This deficiency is common in areas of the world where people do not eat enough of foods that are good sources of vitamin A, such as

• Animal and fish liver
• Orange, yellow, and dark green vegetables and yellow and orange fruits
• Eggs
• Fortified milk products

For example, vitamin A deficiency occurs in southern and eastern Asia, where regular rice, which contains no vitamin A, is the main food. Golden rice has higher amounts of beta carotene, and may decrease vitamin A deficiency.

Disorders that impair the intestine’s absorption of fats can reduce the absorption of the fat-soluble vitamin A and increase the risk of vitamin A deficiency. These disorders include chronic diarrhea, celiac disease, cystic fibrosis, certain pancreatic disorders, and blockage of the bile ducts. Surgery on the intestine or pancreas can have the same effect.

Liver disorders can interfere with the storage of vitamin A. (Most of the body's vitamin A is stored in the liver.)

Causes

Vitamin A deficiency is common among people who have had a severe deficiency of protein and calories ( protein-energy undernutrition) for a long time. People with this disorder do not consume enough vitamin A, and storage and use of vitamin A is impaired.

Diagnosis of Vitamin A Deficiency

• A doctor's evaluation
• Blood tests
• Relief of symptoms when vitamin A supplements are taken
• Doctors suspect vitamin A deficiency based on symptoms, such as night blindness.
• Doctors measure the level of vitamin A in the blood. However, levels do not decrease until the deficiency is severe because the body stores large amounts of vitamin A.
• If people have problems seeing in the dark, eye tests, such as electroretinography, may be done to determine whether vitamin A deficiency is the cause.
• To help confirm vitamin A deficiency, doctors may give people vitamin A supplements to see whether they relieve symptoms

Prevention of Vitamin A Deficiency

To help prevent vitamin A deficiency, people should eat dark green leafy vegetables, yellow and orange fruits (such as papayas and oranges), carrots, and yellow vegetables (such as squash and pumpkin). Other food sources include milk and cereals that are fortified with vitamin A, liver, egg yolks, and fish liver oils. The carotenoids that give fruits and vegetables their yellow, orange, or red color and that are converted to vitamin A in the body, are best absorbed from cooked or homogenized vegetables served with some fat or oil.

Children who live in developing countries and are at risk of vitamin A deficiency should take vitamin A supplements.

Treatment of Vitamin A Deficiency

Vitamin A supplements

People who have vitamin A deficiency are given high doses of vitamin A, usually by mouth, for several days, followed by lower doses until vision and skin improve. Infants should not be given high doses repeatedly because such doses can be toxic.