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After completing this chapter, you should be able to do the following:

  • Identify the six classes of nutrients.

  • Describe the major function of the nutrients.

  • Analyze your diet for nutritional quality using U.S. Dietary Guidelines and MyPlate.

  • Explain the relationship of nutrition to enhancing performance.

  • Describe the advantages or disadvantages of dietary supplementation in the diet.

  • Discuss common eating and drinking practices in the physically active population


  • nutrition

  • diet

  • nutrients

  • macronutrients

  • micronutrients

  • deficiencies

  • undernutrition

  • overnutrition

  • diuretics

  • nutrient dense

  • requirement

  • recommendation

  • foodborne illness

  • salmonella

Why Do You Need to Know About Nutrition?

For a car engine to run smoothly and function efficiently, the car owner must provide the appropriate type and amount of fuel. In the case of a human body, the owner of that body must take personal responsibility for choosing the correct nutrients in the appropriate quantity that provides sufficient fuel to allow the body to function efficiently.

"Sports drinks," "anabolic amino acids," "antioxidants," "fat burners" —it seems that every day we read or hear about the health benefits of some nutrition-related product or service. Nutrition "experts" promote their opinions in the social media, in their blogs, or tweets, on TV or radio. Salespeople in health food stores praise the virtues of nutrient supplements, and friends give advice about diets that guarantee to melt pounds fast. Nutrition appears to be the key that unlocks the door to a healthy, more attractive body. How true are all of the nutrition claims about foods, nutrients, or diet plans? What role does nutrition play in maximizing fitness? Lab Activity 7-1 will help you determine how much you know about nutrition. By understanding the basics of nutrition, you will be more likely to recognize the many forms of nutritional misinformation. And, armed with some basic nutrition information, you will be able to identify "weak" areas of your diet and work to strengthen them. Are you fueling your body with a nutritious diet now? Lab Activity 7-2 will help you assess your eating patterns and find out whether you are currently eating a nutritious diet.

nutrition: the science of certain food substances

Basic Principles of Nutrition

What do you think of when you hear the word diet? Although many people think of losing weight, diet actually refers to your usual food selections. Everyone is on a diet based on the foods that they choose! When a person eats less food in an effort to lose weight, he or she is on a weight reduction diet. Nutrition is the science of consuming certain food substances, nutrients, and how they act to fuel your body's needs. Nutrients perform three major roles:

diet: refers to the types of food substances consumed

nutrients: perform three major roles, including growth, repair, and maintenance of all body cells; regulation ...

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