Description
This book is about vitamin A, an essential micronutrient for humans. The role of vitamin A in vision was discovered in the 1950s, but not until the 1980s was the full scope of its effects on human health understood. It essential nature in sustaining life was discovered in the 1930s, largely forgotten, and then rediscovered almost 55 years later. Today we know that vitamin A deficiency threatens the vision, well-being, and the very lives of millions of children in the developing world. The book describes how we came to discover vitamins and their roles in nutrition. During this time of discovery, a new paradigm was introduced into the understanding of health, namely, that in addition to infectious agents, the absence of essential micronutrients could produce disease, and even death. A chapter is devoted to a simplified outline of the chemistry and biology of vitamin A in its various forms, after which the many effects of vitamin A on human health are described in detail. There are strategies for providing micronutrients such as vitamin A in parts of the world where it is in low supply, including what appears to be a robust and sustainable solution in parts of sub-Saharan Africa that involves the growth of the orange-fleshed sweet potato. A strategy is needed for the three billion people of the world who depend on rice for their well-being, beyond the provision of vitamin A capsules, which provide only partial coverage. A chapter presents and explores a controversial solution, involving genetic engineering of a food crop, for such populations. It closes with a detailed analysis of the arguments for and against this solution, and a plea for evidence-based, case-specific solutions for the vitamin A requirements of children in the developing world.
