Unit 1
An Overview of Nutrition

The human body is constantly undergoing changes that are governed by genetics and that are highly dependent on the availability of nutrients. In this unit, we define the terms nutrition and nutrient, and identify the major classes of nutrients. We also examine some of the factors that influence our food intake. Eating too little or too much can create an imbalance of nutrients and result in nutritional problems; therefore, we discuss different techniques for assessing nutritional status. Finally, we identify the criteria for determining the reliability of nutrition information and its sources.

This unit consists of three sections:

1.1—The Nutrients
1.2—Assessing Nutritional Status
1.3—Appraising Nutritional Information

Objectives

After completing this unit, you should be able to

1. define the term nutrition.
2. define nutrient, and identify the major classes of nutrients.
3. define and differentiate among, calorie, kilocalorie (Calorie), and kilojoule; and give the kilocalorie values (per gram) for carbohydrate, lipid, protein, and alcohol.
4. explain some of the factors that govern the way we eat.
5. identify the four components of a complete nutritional assessment, and describe the type of information supplied by each component.
6. identify the four methods of collecting diet information: 24-hour food recall, food diary or diet record, food frequency, and diet history.
7. list the factors that can influence the nutrient values in the food composition table, and discuss the limitations of food composition tables.
8. describe the criteria for evaluating the reliability of experimental studies or published research.
9. identify some reliable sources of nutritional information.