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Chapter 1: Nutrition and You: An Introduction and How to Achieve a Healthy Diet

  • Page ID
    1824
  • In this Chapter, we provide an overview of nutrition as an evidence-based science and explore the concepts of health, wellness, and disease. We also provide an introduction to the different types of nutrients, health factors, personal health assessment, and the concept of sustainable food systems.

    • 1.1: Chapter Introduction
      Nutrition is an evidence-based science. Nutritional scientists continuously advance our knowledge of nutrition by building on prior research. A primary goal of this text is to provide you with information backed by nutritional science, and with a variety of resources that use scientific evidence to optimize health and prevent disease. In this chapter you will see that there are many conditions and deadly diseases that can be prevented by good nutrition.
    • 1.2: Defining Nutrition, Health, and Disease
      Health is defined as “a state of complete physical, mental, and social well-being, and not merely the absence of disease or infirmity.” World Health Organization.  Disease is defined as any abnormal condition that affects the health of an organism, and is characterized by specific signs and symptoms. Disease affects all three aspects of the health triangle. Good nutrition provides a mechanism to promote health and prevent disease.
    • 1.3: What Are Nutrients?
      Foods contain nutrients that are essential for our bodies to function.  Four of the classes of nutrients required for bodily function are needed in large amounts. They are carbohydrates, lipids, proteins, and water, and are referred to as macronutrients.  Two of the classes of nutrients are needed in lesser amounts, but are still essential for bodily function. They are vitamins and minerals.  One measurement of food quality is the ratio of essential nutrients to the amount of energy in a food.
    • 1.4: Historical Perspectives on Food
      Perspectives and practices related to food and nutrition have greatly changed from the ancient era to today. In the ancient world, location and economic status had a profound effect on what people ate. Also, societies often were based on crop cultivation and livestock rearing, which influenced how people ate, worked, and lived. During the Medieval Era, people became more exposed to food from other parts of the world because of the growing ability to ship goods among other factors.
    • 1.5: The Broad Role of Nutritional Science
      The scientific method is an organized process of inquiry used in nutritional science to determine if the food suspect fits the claim. The scientific method is part of the overall evidence-based approach to designing nutritional guidelines that are based on facts. There are different types of scientific studies—epidemiological studies, randomized clinical interventional trial studies, and laboratory animal and cell studies—which all provide different, complementary lines of evidence.
    • 1.6: Health Factors and Their Impact
      The expression of genes determines all of your traits including your risk for certain diseases. Nutrients can change the way genes are turned “on” and “off,” consequently affecting health. Certain stages of life require changes in nutrition to maintain bodily functions, such as growing. The traits that a person has are largely a product of their genes and environment. One aspect of a person’s environment is socioeconomic status, which is dependent on income, occupation, and education.
    • 1.7: Nutrition and the Media
      Reliable nutritional news will be based upon solid scientific evidence, supported by multiple studies, and published in peer-reviewed journals. Be sure the website you use for information comes from a credible and trustworthy source, such as the USDA Food and Nutrition Center, the HHS, and the CDC.
    • 1.8: Assessing Personal Health
      Some tools to assess your lifestyle and make changes towards a healthier one.  1: Take charge of tracking your personal health.  2: Assess your diet and identify where it can be changed to promote health and prevent disease. 3: Start finding out the medical history of your family and identify the diseases you may be more susceptible to getting. 4: Assess your lifestyle by evaluating your personal habits, emotional health, sleep patterns, and work-life balance. 5: Start living a healthier life.
    • 1.9: Dietary Toolkit
      The government works to provide citizens with information, guidance, and access to healthy foods. How will you decide which information to follow? What are the elements of a healthy diet, and how do you figure out ways to incorporate them into your personal diet plan? The dietary toolkit can be likened to a mechanics toolkit, with every tool designed for a specific task(s). Likewise, there are many tools in the dietary toolkit that can help you build, fix, or maintain your diet for good health.
    • 1.10: A Healthy Philosophy toward Food
      Nutrition promotes vitality and an overall sense of health and well-being by providing the body with energy and nutrients that fuel growth, healing, and all body systems and functions. Good nutrition will also help to ward off the development of chronic disease.  A person is malnourished by being either undernourished or overnourished. Malnutrition results when the body does not receive the required amounts of calories, fats, proteins, carbohydrates, vitamins, and minerals necessary.
    • 1.11: Understanding the Bigger Picture of Dietary Guidelines
      US dietary guidelines are based on evolving scientific evidence and are updated every five years. The goals of the 2015 Dietary Guidelines are to provide guidance for choosing a healthy diet and prevent chronic disease.  To have a healthy eating pattern, reduce the intake of sodium, saturated and trans fats, cholesterol, added sugars, and refined grains. Increase consumption of fruits, vegetables, low-fat dairy products, dietary fiber, and oils.
    • 1.12: What Is Nutritional Balance and Moderation?
      A healthful diet is adequate in providing proper amounts of nutrient-dense foods, is balanced in relation to food types so that one nutrient is not consumed at the expense of another, practices calorie control by supplying food energy to match energy output, is moderate in unwanted constituents, and draws from a variety of nutritious foods.     Nutrient-dense foods contribute to daily nutritional requirements while limiting caloric intake to either lose weight or to maintain a healthy weight.
    • 1.13: National Goals for Nutrition and Health: Healthy People 2020
      Healthy People 2020 is a health initiative with a ten-year objective of helping Americans improve health and well-being, and to live long, healthy lives. The goals of Healthy People 2020 are founded upon a determinants of health approach, which means they are reflective of the circumstances in which people are born, live, and work, as well as the conditions that shape their circumstances such as money, power, and resources at the local, national, and global levels.
    • 1.14: Recommendations for Optimal Health
      The Food Pyramid has been replaced by MyPlate, a system that was designed to be easier to implement. The new MyPlate encourages all plates to be filled with fruits and vegetables (50 percent), protein (25 percent), and grains (25 percent). Half of daily grain intake should be from whole-grain sources. Dairy choices should be switched to low-fat or non-fat sources. A diet rich in fresh fruits and vegetables will help you lose and/or maintain weight.
    • 1.15: Understanding Dietary Reference Intakes
      Nutrient-intake recommendations set for healthy people living in the United States and Canada are known as Dietary Reference Intakes.     The DRIs includes the AI, EAR, RDA, and UL for micronutrients and the AMDR ranges for energy-yielding macronutrients. The DRI provide a set of standards for researchers and government policy-makers, and specifies nutrient consumption guidelines for individuals.
    • 1.16: Discovering Nutrition Facts
      The Nutrition Labeling and Education Act made it a law that foods sold in the United States have a food label that provides the accurate contents of nutrients within them. A Nutrition Facts panel gives information on the amount of servings per container, the amount of calories per serving, and the amounts of certain nutrients. The percent DV is the percentage of the amount of the nutrient in the food in relationship to its recommended intake.
    • 1.17: When Enough is Enough
      Judging portion sizes can be done using your hand or household objects in comparison. It can also be done using the MyPlate guide to determine how much food is a portion for that meal.
    • 1.18: Foodborne Illness and Food Safety
      Foodborne illness is caused by pathogens, such as bacteria and viruses, toxins, such as those produced by molds and poisonous mushrooms, and chemical contaminants, such as pesticide residues and pollutants. A number of government agencies work to regulate food, manage outbreaks, and inform the public about foodborne illness and food safety. Consumers also should take measures to protect their health, including following the rules for four key steps: clean, separate, cook, and chill.
    • 1.E: Nutrition and You (Exercises)