1.1 INTRODUCTION
Obesity is a pandemic which represents one of the most significant public health issues for the world in recent history. It is currently estimated that 2.1 billion people in the world are obese [1]. Furthermore, obesity significantly contributes to both worldwide morbidity and mortality [2]. In 2013, obesity was recognized by the American Medical Association as a disease. Furthermore, research supports that obesity increases the risk for many chronic diseases including cardiovascular disease (CVD), cancer, type 2 diabetes (T2DM), metabolic syndrome (MetS), chronic kidney disease, and many musculoskeletal conditions.
The prevalence of obesity in the United States has been increasing for almost 100 years [3]. Since the 1960s, the National Health and Nutrition Examination Survey (NHANES) has taken an active role in tracking obesity in the United States [4,5]. The prevalence of obesity remained fairly constant between 1960 and 1980. However, according to the NHANES data, in each interval from 1976 to 1980 and 1988 to 1994 the prevalence of adult obesity increased by eight percentage points. Recent data suggest that obesity plateaued with no significant increase in prevalence in the United States in the interval between 2003 and 2010, but increased in the intervals from 2005 to 2006 and 2013 to 2014 [6,7]. The current prevalence of obesity is more than double that of 1970 with 42.5% of the population considered obese and 73.6% considered overweight or obese in the United States
1.2 THE BURDEN OF OVERWEIGHT AND OBESITY IN THE UNITED STATES
Childhood obesity represents a relatively new chronic disease epidemic with significant medical and health implications. The prevalence of children with obesity has increased significantly since the 1980s, paralleling the increase in adults with obesity during this period [8]. The prevalence of obesity among 2–19 year olds in the United States is 18.5% and continues to rise across all age groups. Obesity disproportionately affects black, Hispanic, and other minority youths. Comorbid conditions such as T2DM are projected to increase dramatically as generations of children carry obesity into adulthood.
In addition to the enormous health toll attributable to obesity, the obesity epidemic is also driving enormous costs. It is estimated in the United States, for example, that obesity may cost as much as $147 billion each year [9]. Roughly one-half of this total is paid by the government (i.e. taxpayers), and the other half is paid by private insurers. Thus, taxes and employee premiums (paid by all employees, regardless of weight) finance much of the cost of treating obesity and its related conditions.
It is estimated that an individual with obesity costs a health plan 47% more in healthcare expenditures and an individual who is overweight costs the health plan 16% more annually than healthy weight individuals. For all of these reasons, multiple stakeholders including governments, employers, taxpayers, and employees all have significant motivation to slow down rising rates of obesity, if only for its financial impact.
It is clear that obesity is a complicated, multifactorial problem with numerous external and internal influences which impact obese individuals. There is no question that in the United States, and in most of the Western world, we live in an obesogenic environment (it has even been called a “toxic” environment) for weight gain. There are multiple factors that impact weight gain and obesity including family, culture, community, government, and world food policies. There is also clearly an influence from genetics since some individuals are more likely to gain weight than others and some ethnic groups (e.g. black and Hispanic women) are more affected than others [9,10].
The recognition that obesity is an urgent national imperative has been articulated by multiple evidence-based documents. Perhaps the most prominent of these are the Dietary Guidelines for Americans 2020–2025, which characterize obesity as the leading nutritional health problem in our country [11]. The Physical Activity Guidelines for Americans 2018 (PAGA 2018) comes to similar conclusions. The goal of limiting obesity to no more than 15% of the adult population was articulated in the Healthy People 2020 document [12] and again in the 2030 document [13]. In the 2020 document, this was clearly wishful thinking. The United States is moving away from this goal rather than toward it.
For all these reasons, it is no longer a viable option for healthcare professionals to stay on the sidelines, both as individual practitioners and community leaders, when it comes to the urgent problems of both adults and children with obesity. This is the underlying premise behind the current book.
