Module 4: The Scourge of Eye Health: Vitamin A Deficiency

            “Vitamin A deficiency (VAD) is the leading cause of preventable blindness in children and increases the risk of disease and death from severe infections. In pregnant women VAD causes night blindness and may increase the risk of maternal mortality… Vitamin A deficiency is a public health problem in more than half of all countries, especially in Africa and South-East Asia, hitting hardest young children and pregnant women in low-income countries.”(1) – World Health Organization

4.1 Vitamin A Deficiency (VAD): Causes & Consequences

Some salient statistics from the World Health Organization:
“An estimated 250 million preschool children are vitamin A deficient and it is likely that in vitamin A deficient areas a substantial proportion of pregnant women is vitamin A deficient…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.”(2)

Vitamin A is an essential nutrient for cell growth, wound healing, maintaining healthy skin and lungs as well as maintaining healthy vision. VAD is mostly the result of eating a poor diet, and it is more prevalent amongst the elderly and the poor. Vitamin A is also stored in the body, and sometimes stores of Vitamin A are depleted in illness, pregnancy and lactation.(3) VAD is the leading cause of preventable blindness in children.(4)

VAD leads to night blindness, or the lack of ability to see clearly in the dark. More seriously, it can lead to xerophthalmia, which scars and damages the eye, leading to blindness (more details in 4.2).(5)

4.2 Vitamin A Deficiency: Signs & Symptoms

Eye-related symptoms include:

Other symptoms include:(7)

4.3 Prevention

To prevent or treat vitamin A deficiency,

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Footnotes

(1) "WHO/Micronutrient Deficiencies." World Health Organization. World Health Organization. 9 Jul 2009 <http://www.who.int/nutrition/topics/vad/en/index.html>.

(2) Ibid.

(3) World Health Organization. Department of Vaccines and Other Biologicals & Department of Nutrition for Health Development. Distribution of vitamin A during National Immunization Days. Geneva: 1999. Web. <http://www.who.int/vaccines-documents/DocsPDF/www9836.pdf>.

(4) "Nightblindness and Xerophthalmia: Vitamin A Deficiency - Explore Vitamins (UK)." Explore Vitamins. Explore Vitamins. 9 Jul 2009 <http://www.explorevitamins.co.uk/nightblindness-xerophthalmia-vitamin-a.html>.

(5) Ibid.

(6) Ibid.

(7) Ansstas, George, Jigna Thakore, and N Gopalswamy. "Vitamin A Deficiency." emedecine 16 Jun 2008 Web.09 Jul 2009. <http://emedicine.medscape.com/article/126004-overview>.

(8) Ansstas, George, Jigna Thakore, and N Gopalswamy. "Vitamin A Deficiency: Treatment & Medication." emedecine 16 Jun 2008 Web.09 Jul 2009. <http://emedicine.medscape.com/article/126004-treatment>.

(9) See for example World Health Organization. Department of Vaccines and Other Biologicals & Department of Nutrition for Health Development. Distribution of vitamin A during National Immunization Days. Geneva: 1999. Web. <http://www.who.int/vaccines-documents/DocsPDF/www9836.pdf>.

(10) United Nations Educational, Scientific and Cultural Organization. United Nations Education, . Vitamin A Deficiency (VAD). 2004. Web. <http://74.125.95.132/search?q=cache:W5xuVyg_5N8J:portal.unesco.org/education/en/files/36928/11014809123FINAL_cc3-fnt06vad.doc/FINAL%252Bcc3-fnt06vad.doc+breastfeeding,+VAD&cd=4&hl=en&ct=clnk&gl=us>.