Still, vitamins were entirely unrecognized, and some fatal diseases that we now know to be due to vitamin deficiency were then thought to be due to infection. For instance, when Dutch scientist Christian Eijkman began studying the fatal nerve disease beriberi in the 1880s, he conducted experiments designed to ferret out the causative bacterium. Finally,Eijkman discovered that replacing the polished white rice in a patient’s diet with whole grain brown rice cured the disease. Still, he surmised that something in the brown rice conferred resistance to the beriberi “germ.” It was not until the 20th century that the substance missing in polished rice—the B-vitamin thiamin—was identified and beriberi was definitively classified as a deficiency disease.1 Another B-vitamin, niacin, was discovered through the work of Dr. Joseph Goldberger in the early 1900s. The accompanying High light box describes Dr. Goldberger’s daring work.Nutrition research continued to focus on identifying and preventing deficiency diseases through the first half of the 20th century. Then, as the higher standard of living after World War II led to an improvement in the American diet, nutrition research began pursuing anew objective: supporting wellness and preventing and treating chronic diseases—that is,diseases that come on slowly and can persist for years, often despite treatment. Chronic diseases of particular interest to nutrition researchers include heart disease, obesity, type 2 diabetes, and various cancers. This new research has raised as many questions as it has answered,and we still have a great deal to learn about the relationship between nutrition andchronic disease.
In the closing decades of the 20th century, an exciting new area of nutrition research began to emerge. Reflecting our growing understanding of genetics, nutrigenomics seeks toun cover links between our genes, our environment, and our diet. The Nutrition Debate on pages 35–38 describes this new field of research in detail.
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