Vitamin A deficiency: who is at risk?
According to the World Health Organization (WHO), vitamin A deficiency is present when the level of the vitamin in the blood plasma is less than 10 micrograms per decilitre (µg/dl). But even the range before this (between 10 and 20 µg/dl) is considered to be the beginning of a deficiency.
Vitamin A deficiency is the most common vitamin deficiency worldwide. It is particularly widespread in developing countries. In Germany and other industrialized countries, the vitamin A supply is generally good. Risk groups for vitamin A deficiency are premature babies, children susceptible to infections, pregnant and breastfeeding women, people over 65 and people with an inadequate, predominantly plant-based diet. This is because the fat-soluble vitamin A is mainly found in animal foods. Precursors (carotenoids) are found in plant foods, which are then converted into the active vitamin A in the body.
Vitamin A deficiency: causes
A vitamin A deficiency can have various causes:
- insufficient intake (e.g. unbalanced diet)
- impaired absorption (e.g. due to gastrointestinal diseases)
- poor storage capacity (e.g. due to alcohol abuse)
- increased requirement that is not met (e.g. during pregnancy)
Temporarily low vitamin A levels can also occur with some infectious diseases, such as measles.
Vitamin A deficiency: symptoms
So-called Bitot spots (whitish spots in the palpebral fissure area of the conjunctiva) can also occur as an early symptom.
Other possible symptoms of a vitamin A deficiency:
- Thickened, dry conjunctiva
- Corneal ulcers, possibly with melting of the cornea in an almost unresponsive eye (keratomalacia)
- keratinization of the skin and mucous membranes in the respiratory tract, digestive tract and urinary tract
- weakened immune system
- impaired growth in children
- Disturbance of sperm cell production
Vitamin A deficiency: effects during pregnancy
According to the German Society for Nutrition, pregnant women should take in 1.1 milligrams of vitamin A per day from the 4th month onwards. This is more than the recommended daily requirement for women of childbearing age outside of pregnancy (between 0.8 and 1.0 milligrams, depending on age).
If expectant mothers develop a vitamin A deficiency, this can affect not only their own health but also that of their unborn child: according to studies, the child’s development can be impaired if too little vitamin A is available.
However, expectant mothers should not overdose on vitamin A either, as this can lead to malformations in the child (e.g. cleft palate, growth, liver and eye damage).
