VITAMIN A DEFICIENCY

WHO: Global challenges in nutrition and health

• Protein-energy-malnutrition (Approximately 220 million children under five)
• Iodine-deficiency (Marked improvement in recent years due to enrichment of salt)
• Vitamin A-deficiency (100 million children under five)
• Iron-deficiency (1 billion children and adults)
• Over-nutrition (Several hundred millions in both developed and developing countries)

See WHO's information on Vitamin A deficiency

Clinical vitamin A deficiency:

• Defined as xerophthalmia : 5 million children in pre-school age have clinical symptoms (xerophthalmia)
• Public health problem in 39 countries, 250.000 - 500.000 go blind every year as a result of xerophthalmia.

Causes of vitamin A deficiency

1. Low dietary intake
2. High infection frequency: the vicious circle:

Vitamin A deficiency
→ increased infection risk
→ infections
→ increased vitamin A combustion and reduced vitamin A absorbtion, increased vitamin A elimination
→ more severe vitamin A deficiency

Risk groups/status

Deficiency: children of pre-school age and pregnant and lactating women with a low vitamin A intake, alcoholics, persons with chronic liver disease.

Marginal: children and women living in poverty with an insufficient food supply, populations prone to infections (the vicious circle).

Adequate: typical for a population with good nutrition.

Too much: chronic use of dietary supplements, frequent intake of food items high in vitamin A (e.g. liver).

Toxic: ”food faddists” and users of high-dose supplements, patients treated with retinoids e.g for specific cancer types or skin conditions (acne, psoriasis).