Diets based upon root and tuber crops are found in many specific locations, for example parts of the Pacific and the Andes in South America. But the main areas where such crops still seem to predominate in national diets are in central and west Africa. Of course, quantities of vitamins and minerals are required for an adequate diet. Thus one FAO definition of malnutrition is ‘a pathological state, general or specific, resulting from a relative or absolute deficiency or an excess in the diet of one or more essential nutrients’.
Clearly, this definition can pertain to calories, proteins, vitamins and minerals (Dyson, & Maharatna, 1992). Because food is never distributed equally between all households in a country-the rich typically getting more than average, and the poor typically getting less-FAO then attempts to estimate the distribution of calorie supplies within each national population, using various statistical procedures and assumptions, and whatever information on patterns of household income or expenditure may be at hand.
But perhaps the most contentious step in FAO’s process of gauging the extent of undernutrition is that of estimating national per capita calorie requirements. This involves estimating the basal metabolic rate (BMR) for each country-i. e. the number of calories required for an average person to maintain essential body functions, while lying at complete rest-taking account of variation in factors like national bodyweights and population age composition. Levels of calorie requirements are obtained by multiplying the BMRs by a constant.
The value of this constant has been repeatedly revised upwards with time, which, other things being equal, increases the number of people estimated as undernourished. Finally, comparison of the estimated calorie requirements with the estimated levels and distributions of calorie supplies provides estimates of the numbers of undernourished people (Ehrlich, & Ehrlich, 1990). Clearly, such a complicated and indirect approach, embodying a host of assumptions, and ultimately being based upon rather patchy empirical foundations, is far from ideal!
Quite minor changes to the methods and assumptions can produce very large differences to the estimated numbers of undernourished people. And it is not inconceivable that an organization which is devoted to food and agricultural production may have an interest in presenting estimates of global hunger which err on the high side. Food is a topic full of opposites. Nearly everyone has views. There can be times of feast, and times of famine. Some see human hunger as primarily a problem of production, while others emphasize issues of distribution.
There are those who advocate national self-sufficiency in food, and those who favour policies of unrestricted free trade. Many people regard low food prices as a boon, but most farmers want higher prices. Usually there is some merit in both opposing views. Usually reality and sense rest somewhere in between. Hunger and food insecurity are widespread in the modern world. Sub-Saharan Africa suffers chronically from both phenomena. But South Asia probably contains the greatest number of hungry people.
Levels of per capita food availability are somewhat higher in the Far East, yet there is still much hunger there, and levels of national food security in the region are generally low. In the Middle East relatively high levels of average food availability often belie the extent of food insecurity-and this region is already singularly dependent upon imported food. Even Latin America-with its relatively rich agricultural resource base-confronts serious food problems (Anderson, & Tyers, 1991).
However, while population growth certainly sometimes adds to the task of raising levels of per capita food production (and consumption), it is not the principal cause of contemporary world hunger. It is important to remember that, until relatively recently in human history, ‘hunger’ (at least as we would define it today) has probably been the lot of most people, in most places, at most times. Moreover, we have seen that in recent years and decades food production has generally grown faster than population.
It is true that world grain output has fallen behind demographic growth since 1984. But the reason for this lies largely in the rich world’s overproduction of cereals, compared to the quantities which could reasonably be sold (even at heavily subsidized prices) or otherwise dispensed. Very low selling prices discouraged many of the world’s farmers from growing grain. Deliberate curbs on cereal production – especially, but not exclusively, in North America-constitute a large part of the explanation for the fall in global per capita cereal output since the early 1980s.