Malnutrition

There is an unequal pattern in the global consumption of nutrition, but there are significant health risks to overnutrition as well as undernutrition. Most people associate the word malnutrition exclusively with poverty, hunger, and a deficiency of vitamins and minerals, but there is a strong case for conceptualizing these deficiencies as undernutrition. The prefix mal- means “harmful.” However, there is a substantial and growing body of evidence and appreciation that over nutrition is also associated with substantial health damage, both physical and cognitively, although the pattern of adverse consequences is different from that of several forms of undernutrition.

Overnutrition is defined as the absorption of calories in excess of that required by metabolism and active energy expenditure to maintain a body mass index (BMI [weight (kg)/height (m)2]) in the recommended range. The BMI, originally known as the Quetelet index, became the preferred measure of desirable weight soon after World War II, although other indicators, such as waist-to-hip ratios and arm length are useful for specific purposes. There has been considerable dispute about the recommended range of the BMI. In the United States a BMI of over 30 is considered obese, but in Australia the maximum recommended BMI is 25.

Being severely overweight increases the risk of many chronic diseases, including cardiovascular disease, diabetes, arthritis, and some forms of cancer. Being obese can be stigmatizing, although formerly it was often a sign of prestige, as only those who are affluent can afford to eat calories in excess of their energetic needs. Obesity is still associated with high status in some cultures, such as parts of Polynesia.

Many scholars have pointed to the paradox of how unbalanced our civilization is to tolerate an almost similar number of adversely overnourished people as of undernourished. In some low-income countries, a pattern is emerging of obesity (parents) and underweight (infants) even in the same family. These patterns are not coincidental but rather reflect and maintain a global pattern of inequality with many other manifestations, such as the unequal distribution of rights, income, health, life expectancy, and “entitlement” to many goods and services, including food. However, further discussion of overnutrition is beyond the scope of this entry, which will instead focus on undernutrition.

Hunger is a feeling of discomfort from insufficient food. It is far less precise than data gathered using anthropometric surveys. The concept of food insecurity is broader than undernutrition, as it adds a cultural element and also refers explicitly to an economic dimension. Food insecurity has been [Page 1096]defined as situations in which people lack physical and economic access to sufficient, safe, nutritious, and culturally acceptable food to meet their dietary needs.