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8: Nutrition

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    An array of fresh foods at a buffet with lettuces, chopped vegetables, legumes, and proteins.
    Figure \(\PageIndex{1}\): Nutrition is about color. (Macro Shot of vegetables; Dan Gold via Unsplash)

    Introduction to Nutrition

    Nutrition is a fundamental component of health and well-being, providing the energy and nutrients the body needs to function, grow, and repair itself. Understanding nutrition is essential for making informed choices about the foods we eat and the habits we develop, as these choices directly affect physical performance, cognitive function, and long-term health. This chapter explores the science of nutrition, breaking down key concepts that help individuals meet their daily energy and nutrient needs while maintaining a balanced diet. The roles of macronutrients and micronutrients are examined, and how the body uses food to sustain life. It then examines energy and nutrient requirements, highlighting how factors such as age, sex, activity level, and health status influence dietary needs. Subsequent sections focus on specific nutrients, including carbohydrates, proteins, lipids, vitamins, minerals, and water, explaining their functions, dietary sources, and recommended intakes. Practical applications are also emphasized, with guidance on understanding food labels to make healthier choices, as well as the relationship between nutrition and physical activity. By integrating evidence-based principles with actionable strategies, this chapter provides a comprehensive foundation for developing lifelong healthy eating habits and supporting overall wellness.

    Learning Objectives
    • Learn about the different sources of energy in a balanced diet.
    • Discover the essential nutrients required for health and wellness.
    • Differentiate between the three main types of macronutrients: carbohydrates, proteins, and lipids (fats)
    • Learn about the role of micronutrients in the body's functioning
    • Recognize the importance of water for health and wellness, and its role in body function
    • Learn to read and understand food labels and use them to compare energy and nutrients in food choices
    • Recognize the role of nutrition in physical activity.
    • Determine personal energy intake needs and compare to recommended intakes.

    • 8.1: Nutrition Basics
      Nutrition begins with understanding the essential nutrients the body needs to function, grow, and stay healthy. These nutrients are classified into macronutrients, which provide energy and structural support, and micronutrients, which regulate metabolic and cellular processes. Water is also considered an essential nutrient, as it supports nearly every bodily function despite providing no calories. An understanding of these nutrients can help to create a healthy, nutrient-based diet for everyone.
    • 8.2: Energy and Nutrient Requirements
      Nutrients from food are essential for energy, growth, repair, and regulating body functions. Macronutrients provide energy, while micronutrients support metabolism and overall health. Water is also vital for nearly every body process, even though it has no calories. Foods like fruits, vegetables, eggs, and milk are nutrient-dense, while alcohol lacks nutritional value and can interfere with nutrient absorption.
    • 8.3: Carbohydrates
      Carbohydrates are a primary source of energy and should make up a significant portion of daily calories. Emphasis is placed on choosing nutrient-dense sources such as fruits, vegetables, whole grains, legumes, and low-fat dairy, which provide fiber, vitamins, and minerals. Limiting added sugars and increasing fiber intake are key strategies to support digestive health, reduce the risk of chronic disease, and promote overall well-being through balanced nutrition.
    • 8.4: Protein
      Protein is an essential macronutrient made of amino acids that supports tissue growth, repair, and maintenance. The body requires 20 amino acids, including nine essential ones that must come from food. Complete proteins, found in animal foods and select plants like soy and quinoa, provide all essential amino acids, while incomplete proteins can be combined for balance. Adequate intake, from both plant and animal sources, supports immune function, metabolism, and overall health.
    • 8.5: Lipids (Fats)
      Lipids, or fats, are essential macronutrients that provide energy, support vitamin absorption, protect organs, and aid in hormone and cell function. Dietary fats include saturated, unsaturated, and trans fats, each with different health effects. Unsaturated fats from plants and fish support heart and brain health, while saturated and trans fats increase disease risk. Cholesterol also plays a vital role but requires balance between LDL (“bad”) and HDL (“good”).
    • 8.6: Vitamins and Minerals
      Vitamins and minerals are essential micronutrients that support growth, immune function, energy metabolism, and bone health. Vitamins are classified as fat-soluble or water-soluble, each with distinct absorption, storage, and toxicity risks. Minerals, including major and trace types, regulate fluid balance, nerve function, and structural health. Antioxidants and phytochemicals from whole foods protect cells from oxidative stress.
    • 8.7: Water
      Water is an essential nutrient that supports nearly every bodily function, including temperature regulation, nutrient transport, waste removal, and joint lubrication. The body is 50–60% water, which must be replenished daily through beverages and water-rich foods like fruits, vegetables, dairy, and soups. Plain water is the primary hydration source, while sugary drinks and excessive alcohol should be limited.
    • 8.8: Understanding Food Labels
      Understanding food labels enables individuals to make healthier dietary choices by comparing products and managing nutrition needs. Labels show calories, macronutrients, micronutrients, and %Daily Value to guide intake. Monitoring fats, sodium, and protein helps support health, while ingredient lists, organic, and bioengineered labels provide insight into food quality and production practices.
    • 8.9: Nutrition and Physical Activity
      Adequate hydration and energy intake are essential for supporting exercise performance, recovery, and overall health. Daily fluid needs vary, although active individuals often require more. Exercise increases fluid loss through sweating, making individualized hydration important to prevent both dehydration and overhydration. Carbohydrates fuel moderate- to high-intensity exercise, protein supports muscle repair and adaptation, and fats provide energy at rest and during lower-intensity activity.
    • 8.10: Comprehension Check
      Chapter 8 summary and test your understanding
    • 8.11: Glossary
      Glossary terms for Chapter 8
    • 8.12: References
      References from Chapter 8

    Thumbnail: An array of fresh foods at a buffet with lettuces, chopped vegetables, legumes, and proteins. (Macro Shot of vegetables; Dan Gold via Unsplash)
    This chapter was remixed and authored by Danielle Altman.

    This page titled 8: Nutrition was last modified on Mon, 31 Aug 2026 22:48:08 GMT and is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Danielle Altman, Rusty Johnson, and Cheryl Owiesny.