Vitamin A is a fat-soluble vitamin found naturally in many foods we eat. It is important for a strong immune system, healthy vision and reproduction. Vitamin A also helps the lungs, heart and kidneys function properly.
The two types of vitamin A found in food are preformed vitamin A and provitamin A:
- Preformed vitamin A is found in foods of animal origin, including meat and dairy products.
- Provitamin A is found in foods of plant origin such as fruits and vegetables. The most common form of provitamin A found in foods and supplements is beta-carotene.
Vitamin A deficiency is rare in developed countries. Globally, however, it is one of the most common nutritional deficiencies. Pregnant women and children are most at risk of vitamin A deficiency. 2 This article discusses the signs, causes, complications, and treatment of vitamin A deficiency.
What is vitamin A deficiency?
Vitamin A deficiency usually occurs when a person does not consume enough vitamin A-rich foods to meet their body’s needs. Although rare in developed countries, it remains very common in low-income countries where residents do not have access to dietary sources of provitamin A carotenoids and preformed vitamin A.
Signs and symptoms
Depending on the severity of the deficiency, signs and symptoms may vary. Early signs of vitamin A deficiency include difficulty seeing at night, dry eyes, and dry skin.
Dry eyes can progress to night blindness or difficulty seeing in low light conditions. If the deficiency is not treated, it can lead to complete loss of vision.
Studies also show that vitamin A deficiency is linked to emphysema and other respiratory diseases, including childhood asthma. Therefore, vitamin A supplementation is recommended in high-risk populations for the treatment and prevention of lung disease.
Other symptoms of vitamin A deficiency include:
- Increase in infections
- Dry skin and hair
Causes and risk factors
Pregnant and breastfeeding women, infants and young children in developing countries are most at risk of vitamin A deficiency. It is estimated that 50% of preschool children and pregnant women worldwide are at risk. In fact, vitamin A deficiency is the leading cause of childhood blindness worldwide.
Additionally, premature infants who do not have adequate hepatic stores of vitamin A are at risk of developing a deficiency in their first year of life. Over time, vitamin A deficiency can lead to complications if left untreated.
In addition to vision loss, children who lack vitamin A are at greater risk of stunted growth. Vitamin A deficiency reduces the ability to fight disease and infection. This can lead to increased mortality in children with common childhood infections. Vitamin A deficiency is also associated with pregnancy-related deaths and other negative consequences during pregnancy and lactation.
Diagnosis and evaluation
Vitamin A deficiency is more common if you have an underlying condition that puts you at higher risk of developing a fat-soluble vitamin deficiency. If so, you should get regular tests to make sure you’re not lacking in nutrients.
If you have symptoms related to vitamin A deficiency, such as night blindness or Bitot’s spots, be sure to contact your doctor as soon as possible for an evaluation.
Treatment and prevention
The best way to prevent vitamin A deficiency is to eat a nutrient-dense, well-balanced diet. Vitamin A is found in many foods we eat. It is also added to certain foods such as cereals, juices and milk. Foods Rich in Vitamin A
- Leafy greens like spinach, kale, and broccoli
- Orange and yellow vegetables like sweet potatoes, carrots and squash
- Dairy products
- Beef liver and offal
For most people, an overall healthy diet will allow you to meet your daily vitamin A needs to prevent a deficiency. Make sure your diet is rich in fruits, vegetables, whole grains, lean proteins, and healthy fats.