18 January 2013

Averting Blindness with Vitamin A

The deficiency of vitamin A in a child has the ability to lead to blindness and possible death. A new book by Wilmer Eye Institute at the Johns Hopkins School of Medicine Professor Richard Semba tells of the importance of vitamin A. I had the chance to speak with Dr Semba about his book, The Vitamin A Story: Lifting the Shadow of Death, and why vitamin A deficiency is such an important issue.

AVFTC: What makes vitamin A so important to the health of people?
Richard Semba: Vitamin A is essential for the immune system, growth, reproduction, and vision. Vitamin A-deficient children have weakened immune systems and are at greater risk of death from infectious diseases such as diarrhea and measles. Vitamin A deficiency is primarily a problem among poor families in developing countries and is a classic case of health disparities.
How did you become interested in this line of study?
In the late 1980s I began working with vitamin A-deficient children at the Cicendo Eye Hospital in Bandung, Indonesia. It seemed ironic to encounter so many children going blind and dying from vitamin A deficiency in the lush, green tropical island of Java. This experience generated many questions and a search for solutions.
What accounts for the vitamin A deficiency in some people?
Vitamin A deficiency is the companion of poverty. The main cause of vitamin A deficiency is not eating enough liver, eggs, cheese, whole milk, as well as dark green leafy vegetables, sweet potatoes, papaya, and mango. As to the former, liver and dairy products are usually beyond the financial means of poor families. In regard to the latter, very large amounts of vegetables and fruit must be consumed each day to meet nutritional requirements for vitamin A. Is any child going to eat six to nine cups of spinach every day? Thus, here we have a conundrum for poor families in developing countries.
What interventions exist and how can they be implemented?
UNICEF provides vitamin A capsules to over 100 developing countries worldwide for free. These capsules are distributed to pre-school aged children every six months. Some countries are requiring or encouraging the fortification of certain foods, such as sugar or cooking oil, with vitamin A.
Why is there a push back against using known solutions?
The arguments against vitamin A supplementation and fortification of foods seem irresponsible and unethical to me. Some view vitamin A supplementation or fortification as benefiting the vitamin A manufacturers. In reality, vitamin A is cheap to manufacture, and capsules are provided free through UNICEF. Should we stop childhood immunizations because money goes to vaccine producers? Some say national vitamin A programs should cease as “the solution lies in the hands of the farmers.” 
Does that mean developing country governments should subsidize farmers to provide free dairy products, fruit, and vegetables to poor families, who otherwise could not afford these vitamin A-rich foods? Most developing countries are struggling to provide even basic infrastructure to their people. One benighted nutritionist has gone to the extreme in saying that the solution is not providing vitamin A but the elimination of poverty. How many children must die or go blind while we wait for that utopian goal of no poverty on earth?
The ONE Campaign is pushing Sweet Potatoes as a nutrition solution for places like sub-Saharan Africa. Is it an effective way to deliver vitamin A as opposed to other interventions like fortified foods or pills?
The wider use of sweet potatoes should be encouraged and not considered “in opposition” to vitamin A supplementation and fortification of foods. The two approaches should be considered complementary.
Part of the problem seems to need behavior change. What are ways to support and encourage healthy decisions regarding vitamin A?
Behavior change is largely a concept of rich societies. Poor people in developing countries who are living on a dollar a day do not choose between two behaviors: to eat or not to eat certain foods. Food scarcity and food prices mostly determine what they eat. For example, among poor families in southeast Asia, rice is the dominant part of the daily fare. It is the least expensive food and fills the stomach. An egg is a relative luxury and might appear once a month on the table. Liver and dairy products are way beyond the budget of poor families.
The book launch partners with Sight and Life. Why did you choose that organization as a partner?
The humanitarian initiative Sight and Life has a well-established track record since 1986 of supporting efforts to eradicate vitamin A deficiency in developing countries.
What do you hope people will learn from your book?
History shows us that vitamin A deficiency – once common in places like Europe and the U.S. – was eliminated through a combination of supplementation (cod-liver oil), fortification, increased diversity of diet, and rising economic standards. The historical lesson is that a wide variety of approaches must be taken in reducing vitamin A deficiency worldwide.