This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

You can download an iPhone app for the 13th edition from the App Store (search for Weeks Population).

If you are a user of my textbook and would like to suggest a blog post idea, please email me at: john.weeks@sdsu.edu

Saturday, August 27, 2011

Why Are We Still Even Talking About Vitamin A?

The BBC News today highlights a paper just published in the British Medical Journal that extols the virtue of Vitamin A supplements for children.

UK and Pakistani experts assessed 43 studies involving 200,000 children, and found deaths were cut by 24% if children were given the vitamin. And they say taking it would also cut rates of measles and diarrhoea. The body needs vitamin A for the visual and immune systems to work properly. It is found in foods including cheese, eggs, liver and oily fish.
The incredibly sad part of this is that we have to keep talking about it in order to get the world to remember how important Vitamin A is for children. A very nice history of the discovery of how important Vitamin A can be is told in the PBS special of "Rx for Survival--Back to the Basics." Dr. Alfred Sommer at The Johns Hopkins Bloomberg School of Public Health is interviewed in this program, which I highly recommend to you:
In the early 1970s, Sommer, an ophthalmologist by training, was working in some of the poorest countries on Earth for the Epidemic Intelligence Service of the Centers for Disease Control. There he began to focus his work on a devastating, startlingly prevalent eye condition called nightblindness.
"A child who is night-blind in a village in India or Bangladesh or Nepal literally can't fend for him- or herself," Sommer explains. "While other kids are walking around the village or playing with toys, these children huddle in a corner."
Sommer saw firsthand the tragic consequences of leaving the condition untreated. "The children will go truly blind, because what happens is the cornea, that clear front of the eye, just melts away. And it can melt away in the course of one day." Millions of children were losing their vision permanently, Sommer learned, because of a simple lack of vitamin A in their diet.
Discovered in 1913 by nutritionist EV McCollum, vitamin A was one of the first essential "micronutrients" to be identified. One of its functions is to produce a light-sensitive chemical called rhodopsin in the retina, which allows us to see in low light. This is why carrots help us see in the dark, along with liver and dark green leafy vegetables like spinach — all foods that were missing from the diets of the children Sommer encountered.
There was only one way to find out. Sommer and his team gave an oral dose of vitamin A to 10,000 children and compared them with children not getting vitamin A. The results were astounding: Just two cents' worth of vitamin A given twice a year reduced childhood mortality by a third. "We were absolutely elated," he recalls. "Suddenly you have a very inexpensive, practical way to save more than a million lives a year of young children, year in and year out, and prevent half a million children from going blind."
But critics dismissed Sommer's results as too good to be true, and he couldn't convince them that such a simple solution could save so many lives. "What was most frustrating of all was when you present the hard data and people just say they don't believe it. I mean, how do you deal with that?"
And so it is that decades later we are still having to convince the world that we need to get Vitamin A to children, instead of it just being an automatic thing to do. And don't get me going on people who don't want to give their children vaccinations...

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