By Germaine Cornelissen-Guillaume
Undeniably, obesity has become a major health concern today. Laura Dawes brings a welcome overview of the problem from a historical perspective. She carefully reviews how opinions, practices, and beliefs regarding childhood obesity changed in the 20th century. In sharp contrast with today’s prevalence of the condition, she reminds us how rare it was a century ago. It was then considered that some plumpness was beneficial as it protected children from infectious disease. The book chronicles the course of obesity in children–from infancy through adolescence–in the United States, starting when it first became a medical concern up to now, as it has evolved into a full-fledged epidemic. It examines how answers changed over the years to major questions regarding causes underlying obesity, its diagnosis, and how it should be treated.
The first part of the book is devoted to the problem of diagnosing obesity and measuring body size, body composition, and fat mass. As pediatrics emerged as a medical discipline in the 1870s, interest in body weight stemmed primarily from a concern for the underweight child who failed to strive. By the 1920s, anthropometric measurements facilitated by the availability of inexpensive small scales had become a standard screening procedure, turning medical attention towards excess weight. Factors contributing to the shift in emphasis include a receding threat from infectious disease, improved nutrition, sanitation and housing, vaccination, and the growing awareness that obesity in adulthood was bad for one’s health. Dawes clearly describes the difficulties in establishing reference standards to distinguish between health and obesity, the subjectivity in deriving thresholds, and the importance of measuring body fat in preference to indices based on height and weight. Whereas the body mass index emerged as the primary measure in view of its ease of determination for screening large numbers of children and its correlation with body fat content, the debate continues as the health risks of “normal weight obesity” (excess fat without excess weight) are starting to be elucidated.
The second part of the book reviews how the understanding of causes underlying childhood obesity changed during the 20th century, and how treatment modalities changed accordingly. The picture that emerged was a complex, multifactorial condition, each proposed therapeutic approach fraught with its own problems. Dawes identifies three major vogues. First, childhood obesity was thought to be an endocrine dysfunction that could be fixed with gland-based drugs, notably thyroid and pituitary extracts, in view of their success in treating cretinism and Fröhlich’s syndrome, respectively. With the realization that thyroid treatment was symptomatic rather than causal, working as a slimming agent because it led to a state of hyperthyroidism that poisoned the child, the validity of this approach was questioned. By then, it had been observed that treatment of depression and exhaustion with amphetamines was associated with weight loss in some patients, thought to be related to a lessened appetite and increased activity. It did not take long for amphetamines to become part of the standard therapeutic armamentarium for treating childhood obesity, based on metabolic theories and often used in conjunction with a low-calorie diet. But enthusiasm for this approach faded as did the use of diet pills in general, as dieting alone was considered more appropriate. The development of anti-obesity drugs based on physiological and genetic studies of the body’s signaling hormones continues to this day despite the disappointing results with leptin.
As the contribution of both nature and nurture to childhood obesity became better understood, behavior, emotions, and the influence of family became popular concepts, also relevant to psychology and sociology, beyond just medicine. Based on the idea of energy balance, dieting and exercise, which had always been advocated, were emphasized in the second half of the 20th century, when new evidence from longitudinal studies showed that childhood obesity was likely to persist into adulthood, and actuarial statistics linked obesity in adulthood to a higher mortality rate. Diet books directed at overweight children appeared on the market, first tapping into parental support but recently suggesting that children become personally responsible for their own health. Fat camps also became popular to deal with the ills of the modern environment.
In the third and last section of her book, Dawes examines reasons underlying the increasing demand for child weight-loss treatments, childhood obesity having reached epidemic proportions. The increase in prevalence was too large and happened too fast to have a genetic origin. Childhood obesity became viewed as a symptom of social and cultural failure, a thrifty genotype further complicating the negative effects of modern lifestyle. The author singles out television and television advertising of unhealthy food to children as a major culprit, while examining the particular choices, decisions, and policies that shaped American society in the second half of the 20th century. She also asks whether the courts could and should play a role in either individual or public health.
Laura Dawes’ historical lens on childhood obesity offers hope by its powerful way of undoing the sense of inevitability of the situation as she points out that choices made, options discounted, and pathways taken, reflecting social values as much as scientific knowledge, may further evolve, this time to reverse course. She is very skillful in illustrating how each step associated with the changing understanding of childhood obesity parallels medical and scientific progress offering new insights into the condition.
The combination of stories and anecdotes with an impressive number of scientific facts presented clearly and concisely makes Childhood Obesity in America an easy and interesting read. The mention of critical periods in the course of pregnancy as well as growth and development is particularly appreciated as timing offers a further opportunity to deal with the problem. When to eat also matters in relation to weight gain versus weight loss.
This book is an excellent example of how much can be learned from history, something that should be encouraged in all scientific matters.
Germaine Cornelissen-Guillaume is a professor of integrative biology and physiology and director of the Halberg Chronobiology Center at the University of Minnesota, Twin Cities.