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4: Body Composition and Obesity

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    73811

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    Learning Objectives

    By the end of this chapter you will be able to:

    • Recognize the role fat plays in health and disease
    • Explain the prevalence of obesity
    • Compare and contrast the use of BMI and Body Composition measurements
    • Describe negative health consequences of obesity and overweight
    • Explain the difference between type 1 and type 2 diabetes
    • Identify actions that could be implemented to reduce obesity
    • Recognize the signs of body dysmorphic disorders and eating disorders

    How much of your body weight comes from your bones, muscles, organs, or body fat?

    Have you ever tried a diet to lose weight?

    Are there differences in health outcomes based on where you store body fat?

    • 4.1: Introduction to Weight Management
      This page covers body weight and composition, emphasizing the prevalence and risks associated with overweight and obesity compared to underweight. It defines key concepts, including total body mass and the composition of fat, muscle, and bones. The chapter outlines essential body fat ranges, explains the Calorie Balance Equation, and discusses metabolism's role in weight management.
    • 4.2: Obesity Epidemic
      This page discusses the alarming rise in obesity rates in the U.S. and globally over recent decades. In the U.S., adult obesity increased from 22.9% in 1988-1994 to 42.4% in 2017-2018, with severe obesity rising from 2.8% to 9.2%, and nearly 19.3% of children are now affected. Globally, obesity has nearly tripled since 1975, with 39% of adults overweight and 13% obese, indicating a significant health concern surpassing underweight conditions.
    • 4.3: Negative Health Implications of Obesity
      This page discusses the impact of obesity on health, highlighting its association with serious conditions like diabetes and mental health disorders. It details the two main types of diabetes: type 1, primarily affecting youth, and type 2, linked to insulin resistance in adults. With over 122 million Americans affected, it emphasizes risk factors for type 2 diabetes, including obesity and lifestyle choices, and stresses the importance of preventive measures through a healthy lifestyle.
    • 4.4: Assessing Body Composition
      This page covers BMI as a common screening tool for weight categories, while pointing out its limitations in assessing body composition. It stresses the need to understand body fat distribution, distinguishing between subcutaneous and visceral fat and their health effects.
    • 4.5: Factors Contributing to Obesity
      This page covers the multifaceted nature of weight management, detailing how obesity stems from both modifiable factors (lifestyle choices) and non-modifiable factors (genetics, age, sex). It explores the influence of environmental elements like geography and community design, as well as individual aspects such as race and health conditions. The interplay between genetics and environmental factors in contributing to obesity risk is emphasized, highlighting its complexity.
    • 4.6: Weight Loss Strategies
      This page focuses on weight loss strategies, highlighting goal setting, lifestyle assessment, and tracking food intake. It discusses effective weight loss programs that provide behavioral treatment and support, along with dietary recommendations and the role of bariatric surgery for severe obesity.
    • 4.7: Body Image, Eating Disorders, and Low Body Weight
      This page covers body image, outlining its cognitive, perceptual, affective, and behavioral dimensions, and examines factors influencing it, such as media and self-esteem. It contrasts positive body image, marked by acceptance and confidence, with negative body image, linked to shame and dissatisfaction, potentially resulting in eating disorders. Various eating disorders like anorexia nervosa, bulimia nervosa, and binge-eating disorder are described, along with their symptoms and complications.
    • 4.8: End-of-Chapter Material
      This page highlights the importance of fat in health and the limitations of Body Mass Index (BMI) as a measure of healthy weight. It discusses the obesity epidemic and factors leading to it, including lifestyle, environment, and genetics. The need for a healthy diet and regular physical activity for effective weight management is emphasized, mentioning the health risks associated with both overweight and underweight conditions.

    The information in this chapter comes primarily from the following websites:

    This page titled 4: Body Composition and Obesity is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Kelly Falcone via source content that was edited to the style and standards of the LibreTexts platform.