Hunger Math is a resource book for persons working on the problem of world hunger. What is hunger? How widespread is hunger? What is the number and percentage of undernourished persons worldwide? In which regions do most undernourished persons live? Which nations are most severely affected? How many calories does a person need per year? How should those calories be divided among the three macronutrients: protein, fat, and carbohydrates? Since most of the hungry have some food, how many calories and how much of each macronutrient do undernourished persons still need? That's chapter 1. The one billion hungry persons in the world need sufficient total kilocalories. They also need sufficient amounts of protein, fat, and carbohydrates. The data and calculations in chapters 2 through 6 analyze various staple crops (food plants that provide substantial amounts of one or more macronutrients) in order to determine which crops would be most effective in alleviating world hunger. Chapter 7 presents an overview of the contributing causes of world hunger: inequitable distribution of food, the Western pattern diet and obesity, the extensive waste of food in wealthy nations, insufficient agricultural production of protein and fat, feeding livestock high-quality grain and soy, the use of farmland to grow biofuel, the lack of fertilizer and irrigation resources in the developing world, the commercial nature of the food and agricultural system, the development of crops for commerce rather than health, the persistence of illiteracy in developing nations, the lack of mechanized agriculture, inequitable distribution of land, misguided government policies, and the need to put more fertile land into agricultural production. Chapter 8 discusses 15 possible solutions to world hunger, based on the data, calculations, and conclusions earlier in the book. These solutions are essentially the antithesis of the contributing causes. Any one of these proposed solutions could, in theory, end or at least substantially alleviate world hunger. But as a practical matter, no single solution is likely to be implemented to such a great extent as to end hunger. The best approach is every approach. Every possible solution to hunger should be attempted, concurrently. What can you as an individual do to address hunger? Chapter 9 presents my suggestions, as well as actions that organizations, small and large, might take to improve our response to world hunger.