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Paul D. Coverdell World Wise Schools

Paul D. Coverdell World Wise Schools

Global Issues | Nutrition


A diverse and nutritious diet is essential for a healthy life. People who are well nourished typically have fewer illnesses and are better able to live productive lives than those without a complete and balanced diet.1 The concept of malnutrition is sometimes confounded with having a lack of sufficient food or nutrients. While this can be a kind of malnutrition, it is only a part of the issue. The World Health Organization defines malnutrition as "inadequate or excess intake of protein, energy, and micronutrients such as vitamins."2 Also included as a part of malnutrition are the infections and disorders that can occur when a person does not consume a healthy diet. 2

Undernutrition is a type of malnutrition that encompasses insufficient intake of protein, calories, vitamins, or minerals. It is a particular concern for very young children, whose cognitive function can be permanently impaired without proper nutrition early in their development. Protein-energy malnutrition (PEM) , or inadequate intake of calories or protein, can affect growth, the ability to resist infections or recover from disease, cognitive function, the ability to do physical work, and the ability for nursing mothers to produce milk.3 These issues are especially prevalent for children in developing countries, where nearly one in four children under age five are underweight.4

Lack of certain types of nutrients can also be forms of undernutrition. People who don't eat or absorb enough iron may develop iron deficiency anemia, the most common and widespread nutritional disorder in the world,15 which can delay cognitive development in children, increase risk for infection, and cause weakness and fatigue.5Iodine deficiency , one of the leading causes of impaired cognitive development, has been cut in half over the past decade, largely due to efforts to improve global access to iodized salt.6 Vitamin A deficiency , the leading cause of preventable blindness in children, which can be reduced by improved access to diverse fruits and vegetables.7

Another form of undernutrition is known as secondary malnutrition . This means that a person's body does not fully utilize or absorb the nutrients they eat.1 Secondary malnutrition is often a result of diarrheal diseases, which are common in regions where people have limited access to sanitation and clean water. Diarrheal diseases caused by drinking contaminated water can prevent the body from digesting food normally and making use of its nutrients.

A final form of malnutrition is the overconsumption of calories, especially from foods with low nutritional value. This can lead to a person becoming overweight or obese, putting them at risk for developing chronic diseases such as Type 2 diabetes , cardiovascular disease, and certain types of cancer . Overweight and obesity are affecting children and adults, in both developing and developed countries, at a growing rate. Worldwide obesity has doubled since 1980.9 Today, 65% of people in the world live in countries where being overweight leads to more health problems than being underweight.9 Overweight and obesity are measured by calculating a person's body mass index , a measure of body fat based on height and weight.10

The World Health Organization has called undernutrition and the global obesity epidemic a "double burden" of disease.9 While many countries, especially low and middle-income countries, continue to experience problems of infectious disease linked with undernutrition, they are also experiencing considerable increases in chronic diseases linked with being overweight or obese. Globally, about 1 billion people in the world are hungry and about 1 billion are overweight.11

In the United States, nutritional issues continue to be national health concerns. Since 1980, hunger in the United States has gone from affecting 20 million Americans to affecting 49 million. Simultaneously, the obesity rates for American adults doubled; for American children, obesity rates tripled.11 In the U.S., national nutrition initiatives are focused on goals including providing better access to nutritious foods?such as through the national school lunch program; increasing the proportion of adults and children who are a healthy weight; reducing hunger by reducing household food insecurity; and reducing overconsumption of unhealthy fats, sugars, and sodium while increasing consumption of whole grains, and a wide variety of fruits and vegetables.12

Looking at nutrition globally, many of the issues in the world are similar to the United States. Today, more than 50% of the world lives in urban areas; by 2050, more than 70% of the world's population will be urban.13 Increased urbanization is linked with particular health concerns, including greater availability of unhealthy food choices, such as fast food, combined with less physical activity. Unique challenges also exist in rural areas, especially where people live as subsistence farmers. Many of the world's undernourished people are directly involved in food production,14 but may lack the resources-such as productive soil-necessary to produce a diverse diet to meet their families' nutritional needs.

Peace Corps Volunteers assist communities with a variety of issues related to nutrition. Health volunteers may provide education and support for groups of people with unique nutritional needs, such as pregnant women, new mothers, and young children. Water and sanitation volunteers may help communities improve access to consistent clean water and sanitation, to help prevent waterborne illnesses that can lead to malnutrition. Agriculture Volunteers assist farmers with gardening practices to improve their soil's productivity and grow more diverse crops in home and school gardens. To learn more about Peace Corps Volunteers' work related to nutrition issues, visit World Wise Schools' Global Issues page.


1. World Health Organization (WHO)
2. World Health Organization (WHO)
4. United Nations Millennium Development Goals
5. World Health Organization (WHO)
6. World Health Organization (WHO)
7. World Health Organization (WHO)
8. World Health Organization (WHO)
9. World Health Organization (WHO)
10. Centers for Disease Control and Prevention (CDC)
11. 30 Project
12. HealthyPeople.gov
13. World Health Organization (WHO)
14. Food and Agriculture Organization (FAO)



Malnutrition: Inadequate or excess intake of protein, energy, and micronutrients.

Undernutrition: Insufficient food and nutrient intake, often accompanied by repeated infectious diseases

Protein-energy malnutrition (PEM): Undernutrition; insufficient calorie or protein intake

Iron deficiency anemia: A health condition resulting from insufficient iron intake; leads to cognitive impairment, increased risk for infection, weakness and fatigue.

Iodine deficiency: Insufficient intake of the mineral iodine; leads to impaired cognitive development

Vitamin A deficiency: Insufficient intake of Vitamin A (usually from fruit and vegetable sources); can lead to blindness

Secondary malnutrition: Insufficient absorption or utilization of consumed nutrients

Chronic disease: Long-lasting or recurrent diseases like cardiovascular disease and Type II diabetes

Type 2 Diabetes : Chronic disease in which the body does not produce insulin or cells ignore insulin

Cardiovascular disease : Diseases affecting the heart or blood vessels

Body mass index (BMI): A measure of body fat based on height and weight