- Vitamin A is essential to vision, wound healing, bone formation (e.g., teeth), healthy skin and growth, mucous membranes, and lactation. Further, it may also be a factor in preventing cancers. It is important to the immune function, and has been shown to have antiviral properties.
- In the United States, this disease is most often seen in the elderly and poor. In the rest of the world where vitamin deficiencies are more common, it is one of the most common causes of blindness.
- The major sources of vitamin A
include vegetables, milk, eggs, kidney beans, fish (cod and
halibut), and liver. In the body, beta-carotene from plants
such as carrots, apricots, broccoli, and other dark green
leafy vegetables is converted to vitamin A.
- Night blindness (difficulty seeing at night or in dim light) may be the first symptom of Vitamin A Deficiency.
- Other symptoms include dry eye, loss of taste, poor wound healing, and the formation of small, white spots in the inner eyelids.
- Eventually, vitamin A-deficient
patients develop problems with the cornea (the clear part of
the eye) and may even become
- Vitamin A Deficiency is usually due to poor diet. At highest risk are the elderly and the poor.
- It is very common in other parts of the world where poor nutrition is endemic.
- It also tends to occur in patients
with problems absorbing nutrients from the intestine, or in
those who abuse mineral
- A problem seeing at night suggests the possibility of Vitamin A Deficiency.
- Blood tests are available to check
vitamin A levels.
- If detected early, treat with 30,000 IU of vitamin A daily for a week.
- In cases of advanced Vitamin A Deficiency, 20,000 IU of vitamin A per kilogram of body weight is given every day for at least 5 days.
- Treatment needs to be started as
soon as possible. If it is delayed too long, problems may
- A healthy diet will help prevent
the complications of Vitamin A Deficiency. Foods rich in
vitamin A include milk, cheese, liver, kidney, cod oil,
carrots, sweet potatoes, broccoli, spinach, cantaloupe, pink
grapefruit, and most leafy green vegetables.
Vitamin A Toxicity
- This is a potentially serious problem. It usually occurs by taking more that 50,000 IU per day for more than 3 months. It can lead to dry skin, mouth sores, vomiting, and poor appetite. Eventually, it can cause increased pressure within the brain, headaches, and problems thinking clearly. It may also lead to an enlarged liver or to liver failure.
- Some may take too much vitamin A at once, absorbed via overdose or by eating polar bear liver. This can cause stomach pain, nausea, vomiting, headache, and difficulty sleeping. The treatment is to stop taking vitamin A immediately. The symptoms usually improve in a few days.