Vitamin A is a nutrient necessary for cell development, reproductive health, vision, bone growth, immune function, and organ function. You can find it in foods like milk, eggs, green leafy vegetables, salmon, and fortified cereals. While it’s rare for people in the United States to have a vitamin A deficiency, you can develop it if you don’t get enough vitamin A to meet your body’s needs.
Vitamin A is important for your immune system health. When you’re deficient in it, you may be more prone to infections in the:
- Gastrointestinal system: Having low levels of vitamin A can damage the lining of your GI tract, also known as the gut, which is the tube that carries food through the body. People with vitamin A deficiencies may be more vulnerable to gut infections, such as Giardia. Giardia causes diarrhea and malabsorption, which is when it’s difficult to digest or absorb nutrients in the intestines.
- Urinary Tract: This is the body’s system that makes and removes urine from the body. It includes the kidneys, bladder, urethra, and ureters, small tubes that carry urine from the kidneys to the bladder. Being deficient in vitamin A can weaken the urinary tract’s protective layer, which prevents bacteria from getting in, leading to more frequent urinary tract infections (UTIs).
- Respiratory system: Because low vitamin A levels can affect the immune system, this can make you more vulnerable to respiratory infections, which affect the nose, throat, airways, and lungs. Infections include the common cold, the flu, and pneumonia.
Vitamin A deficiency may cause gradual vision loss or xerophthalmia, a serious dry eye condition that can lead to night blindness. Night blindness, which can be one of the first signs of vitamin A deficiency, makes it difficult to see in the dark or low-lit areas, resulting in difficulty driving at night. Untreated vision loss due to vitamin A deficiency can eventually lead to blindness.
Moderate and severe vitamin A deficiencies can lead to:
- Impaired tooth formation
- Incomplete development of tooth enamel (the thin, outer coating of the tooth)
- Periodontitis (gum disease)
Vitamin A is important for healthy bones. Some research suggests that maintaining the right amount of vitamin A for your body can lead to better bone strength and a lower risk of fracture (broken bones). However, getting too much or too little vitamin A can lead to brittle bones and make you more prone to damage.
More research is needed to better understand the differences in these findings and how exactly the source of vitamin A may impact bone health.
Underconsuming vitamin A can lead to hair loss. One of the main active derivatives of vitamin A, retinoic acid, impacts hair health and growth. Retinoic acid regulates hair follicle stem cells and impacts the functioning of the hair growth cycle.
Overconsuming vitamin A can also lead to hair loss, so having a proper intake of vitamin A through diet or supplementation can help prevent hair loss.
Vitamin A deficiency can lead to a skin condition called phrynoderma, a type of follicular hyperkeratosis that causes small, hardened bumps on areas of the body such as the shoulders, buttocks, elbows, and knees. Follicular hyperkeratosis happens when the hair follicles become clogged with keratin (a protein found in the skin).
Symptoms of vitamin A deficiency in children include:
- Diarrhea, possibly with vomiting
- Cough with fever
- Bitot spots, which are triangular or oval-shaped, foamy lesions on the surface of the eye
- Blindness
However, vitamin A deficiency is not common in the U.S. It’s more often seen among children 5 or younger experiencing malnutrition in developing countries.
People who are pregnant or breastfeeding in developing countries are at a higher risk for vitamin A deficiency. This is because they may not be able to obtain enough vitamin A from food and will require supplements to meet their daily needs.
Vitamin A deficiency in pregnant people can result in anemia, night blindness, a compromised immune system, and a higher chance of contracting infections. Around the world, 15% of pregnant people experience vision loss due to vitamin A deficiency. This is uncommon in the U.S., though.
Though rare, vitamin A deficiency can become chronic (long-term). Chronic vitamin A deficiency can lead to a higher risk of infections, such as measles, and respiratory diseases, such as pneumonia.
Chronic vitamin A deficiency can also cause anemia, a condition where the body does not have enough red blood cells to carry oxygen throughout the body.
See a doctor if you experience any vitamin A deficiency symptoms, such as vision loss, dry or inflamed eyes, night blindness, and recurring infections. While vitamin A deficiency is not common in the U.S., a provider can determine whether it or something else is causing your symptoms. A doctor can speak with you about your symptoms and order the appropriate diagnostic tests.
Vitamin A deficiency is when your body lacks enough vitamin A to properly function. This can lead to symptoms such as vision loss, hair loss, night blindness, and infections. The deficiency is rare in the U.S., more commonly affecting people in developing countries who have malnutrition. If you have any symptoms that you suspect may be from a vitamin deficiency, consider reaching out to a doctor for guidance.
