Preface

Obesity is considered one of the most important factors associated with overall health. There are several definitions for obesity, the most common being body mass index (BMI). Individuals with a BMI of 25 or more are considered overweight and those with a BMI of 30 or more are considered obese. There is convincing scientific evidence to indicate a positive association between obesity and several human health disorders such as cardiovascular diseases like heart disease and stroke, high blood pressure, type 2 diabetes, osteoarthritis, high cholesterol, and asthma and chronic obstructive pulmonary disease, among others. The good news is that obesity is a treatable health disorder. However, the bad news is that despite efforts by health professionals to regulate obesity, its prevalence has increased globally in the past two to three decades. Obesity was shown to be only behind high blood pressure, smoking, and high blood sugar in terms of number of deaths. A better understanding of the causes of obesity and mechanisms by which obesity increases the risk of human diseases can and will lead to developing effective strategies that could save lives. Studies have shown conclusively that genetic, environmental, and lifestyle factors, individually and collectively, influence the prevalence of obesity. Diet and exercise are among the important lifestyle factors.

*Role of Obesity in Human Health and Disease* contains chapters authored by international researchers that address some important aspects of the relationship between obesity and human health.

This book is organized into three sections. Section 1 "Obesity and Health," contains five chapters. The emphasis of Chapter 1 is on how food intake in various Japanese populations is correlated to BMI. Since BMI is an important indicator of obesity and health, this chapter provides an important understanding of how management of food intake can be a good strategy to control obesity and thereby health and quality of life. Chapter 2 provides a basic understanding of the causes and effects of endocrine disorders on obesity. This knowledge can be used effectively in the management of endocrine disorders and thereby obesity. Chapter 3, which is a review of the most recent research being carried out in the area of obesity and health, provides information about the nature of this research and the direction of future research. Chapter 4 addresses the relationship between obesity and endometrial cancer. The information provided in this chapter goes beyond the scope of cancer and provides insight into suggested mechanisms and management strategies that can be used to undertake research in other areas of health disorders as they relate to obesity. Chapter 5 looks at the recent popularity of a ketogenic diet and how it relates to sarcopenic obesity-related health issues. It provides some new guidelines regarding the role of diet in the management of obesity and health.

Section 2, "Causes of Obesity," contains two chapters. of Chapter 6 focuses on understanding the role of lifestyle factors on obesity and thereby overall health. Chapter 7 takes a broader approach to understanding the multiple causes of obesity. Both these chapters are important for understanding the causes of obesity, which can then be used to develop effective strategies to control obesity and improve the quality of human health.

Section 3, "Mechanisms by Which Obesity Influences Health Risks," contains three chapters. Chapter 8 looks at obesity in a pediatric patient and how basal metabolic profile might be an important influential factor. Chapter 9 presents information about leptin and its role in oxidative stress-induced apoptosis. Although it does not directly address obesity, it does deal with oxidative stress as a working mechanism perhaps for other human health disorders including obesity. Finally, Chapter 10 provides an interesting alternate model of *Drosophila* to study obesity by exploring the central taste circuits of fruit flies. It is possible that knowledge gained through this model may lead to applications for humans.

Overall, this book provides important information to health professionals, researchers, and other scientists that will be very useful in understanding the pathobiology of obesity, its causes, and mechanisms by which it can influence human health. The chapters provide thought-provoking ideas for future research in this important area of human health as well as for developing applicable and effective strategies to manage obesity and thereby improve human health and quality of life.

> **Dr. Venketeshwer Rao and Dr. Leticia Rao** University of Toronto, Canada
