Many people in the developing world do not get enough vitamin A or beta-carotene from the food they eat, contributing to the serious public health problem of vitamin A deficiency.
Vitamin A is an essential nutrient needed for the visual system, growth, development, and a healthy immune system. Everybody needs vitamin A to grow and thrive, particularly mothers and young children.
Vitamin A is found in animal products and breastmilk. Carotenoids are substances like beta carotene that the body converts into vitamin A. They are found in orange-colored fruits and vegetables and in dark-green leafy vegetables.
Vitamin A deficiency
Vitamin A deficiency (VAD) results from a lack of vitamin A in the diet. VAD can also be caused by infections that reduce appetite or the body’s ability to absorb vitamin A.
Persistent VAD is the leading cause of preventable childhood blindness and increases the risk of death from common childhood infections. VAD remains a serious global public health problem where an estimated 250 000 to 500 000 vitamin A-deficient children become blind every year, half of them dying within 12 months of losing their sight. VAD can damage the immune system and decrease the body’s ability to resist or fight infections, therefore increasing the risk of mortality from common diseases especially among young children. VAD may also result in impaired vision, including night blindness (the inability to see at night or in dim light) and may result in permanent, partial, or total blindness if left untreated.
Providing adequate amounts of vitamin A, on the other hand, reduces overall child mortality by 23%.
Vitamin A deficiency is most common among young children and pregnant and nursing women as they have increased nutrient requirements.
The World Health Organization (WHO) estimates that 190 million preschool children and 19 million pregnant women are vitamin A-deficient globally. Children with vitamin A deficiency are more likely to suffer from poor health and premature death. Vitamin A deficiency is the leading cause of preventable blindness among children in developing countries. Each year, up to 500,000 children go blind as a result of this condition. Half of them die within 12 months of going blind.
The poor in the developing world, who live primarily on a diet of starchy staples that lack vital micronutrients like vitamin A (such as rice), are particularly vulnerable to vitamin A deficiency.
Vitamin A deficiency in Asia
Asia has one of the highest prevalence of vitamin A deficiency in the world, with the most clinical cases found there. Vitamin A deficiency is still considered a public-health problem in many countries of Asia including the Philippines, Bangladesh and Indonesia.
- According to the most recent National Nutrition Survey conducted by the Department of Science and Technology – Food and Nutrition Research Institute (DOST-FNRI), in the Philippines, VAD among preschool children has increased from 15.2% in 2008 to 20.4%.
- In Bangladesh, one in five children is living with VAD. The prevalence appears to be higher among children living in slums at 38% (among pre-school aged children) and 27 per cent (among school aged children.
- In Indonesia, 20% of preschool-age children have VAD.
- promotion of optimal breastfeeding practices;
- promotion of proper complementary feeding practices;
- nutrition education and consumption of a diversified diet that includes nutrient-rich fruits and vegetables and foods from animal sources;
- vitamin A capsule supplementation;
- food fortification; and
- other public health measures, including control of infectious diseases.
These approaches to VAD have had real successes. However, VAD remains a public health problem in many parts of the world. Target populations are sometimes missed with these interventions, especially in hard to reach areas.
If proven to be efficacious and improve vitamin A status, Golden Rice has the potential to be an intervention that could be used to complement these proven VAD control approaches.
Because rice is widely produced and consumed, Golden Rice has the potential to reach many people, including those who do not have reliable access to or cannot afford other sources of vitamin A.
Golden Rice is intended to be used in combination with existing approaches to overcome VAD, including eating foods that are naturally high in vitamin A or beta-carotene, eating foods fortified with vitamin A, taking vitamin A supplements, and optimal breastfeeding practices.
The body converts beta-carotene in Golden Rice to vitamin A as it is needed. According to research published in the American Journal of Clinical Nutrition in 2009, daily consumption of a very modest amount of Golden Rice – about a cup (or around 150 g uncooked weight) – could supply 50% of the Recommended Daily Allowance of vitamin A for an adult.