What is vitamin A deficiency?

Vitamin A deficiency happens when your body doesn’t have enough vitamin A. Vitamin A deficiency usually results from what you do and don’t eat. However, a health condition can also cause it. Your body needs a certain amount of vitamin A to function well.

Vitamin A deficiency is rare in developed countries like Australia where you can generally get fresh produce. You can get enough vitamin A by eating fruit, vegetables and health proteins.

Vitamin A is a fat-soluble vitamin. This means it gets stored in your body’s own cells. If you don’t eat vitamin A-rich foods for a couple of days, you are unlikely to be deficient.

Go here for more information on vitamin A and your health and why you need vitamin A-rich foods in your diet.

What are the symptoms of vitamin A deficiency?

Vitamin A supports good vision. Symptoms of lacking vitamin A include struggling to adjust to low light (‘night blindness’) and xerophthalmia (very dry eyes due to poorly functioning tear ducts).

Problems with vision can often be the first sign of illness associated with vitamin A deficiency.

Am I at risk of vitamin A deficiency?

Because people can generally get vitamin A-rich food in Australia, most deficiency disorders result from illness, injury or restrictive diets.

People at risk of vitamin A deficiency include those with intestinal problems that reduce their ability to absorb vitamin A. Other health conditions linked with vitamin A deficiency are:

• liver disease
• alcoholism
• major gastrointestinal surgery

Anorexia nervosa and other psychiatric disorders can cause poor absorption of vitamin A from foods, which can lead to deficiency.

The Australian Government publishes the recommended dietary intake (RDI) for all vitamins. It is important to check that you get the correct amount of each vitamin. The best way to give your body vitamins is to eat a varied diet that includes a range of fresh fruit and vegetables. The RDI for vitamin A ranges from 250μg (micrograms) daily for infants 0-6 months of age, to 900μg daily for males and 700μg daily for females.

If you are concerned about how much vitamin A you are getting, particularly if you are pregnant or breastfeeding, speak with your doctor or consult a dietitian for advice.

What happens if I have too much vitamin A?

Vitamin A is a fat-soluble vitamin and can accumulate in your body. If you take in more than you need over an extended period, vitamin A will slowly build up in your body. You are unlikely to experience health problems if you get many vitamins from food. However, vitamin supplements (such as vitamin pills or drinks) may cause health problems.

In some rare cases, where a diet involves eating lots of a certain food, someone might get an unhealthy build up over time. For example, very large quantities of carrot juice or liver might cause vitamin A to build up.

There is also an increased risk of birth defects associated with having too much vitamin A. If you are pregnant, it is important that you don’t take too much.

The NSW Cancer Council has reviewed the data on the safety of high-dose beta-carotene. It has concluded that people should avoid taking high doses (more than 18 mg) of beta-carotene supplements, especially if they smoke.

There is also some evidence to suggest that having more than an average of 1.5 mg (1,500 µg) a day of vitamin A over many years can affect your bones, making them more likely to fracture as you get older.

This is important for older people to consider, especially post-menopausal females, who are already at increased risk of osteoporosis.

If you are concerned that you have taken too much of a vitamin A supplement, call the Poisons Information Centre (13 11 26) immediately.