Concern regarding “overweight” and “obesity” is reflected in a diverse range of policy measures aimed at helping individuals reduce their body mass index (BMI). Despite attention from the public health establishment, a private weight loss industry estimated at $58.6 billion annually in the United States, unprecedented levels of body dissatisfaction and repeated attempts to lose weight, the majority of individuals are unable to maintain weight loss over the long term and do not achieve the putative benefits of improved morbidity and mortality.
Concern has arisen that this weight focused paradigm is not only ineffective at producing thinner, healthier bodies, but also damaging, contributing to food and body preoccupation, repeated cycles of weight loss and regain, distraction from other personal health goals and wider health determinants, reduced self-esteem, eating disorders, other health decrement, and weight stigmatization and discrimination. As evidence-based competencies are more firmly embedded in health practitioner standards, attention has been given to the ethical implications of recommending treatment that may be ineffective or damaging.
A growing trans-disciplinary movement called Health at Every SizeSM (HAES)2 shifts the focus from weight management to health promotion. The primary intent of HAES is to support improved health behaviors for people of all sizes without using weight as a mediator; weight loss may or may not be a side effect.
HAES is emerging as standard practice in the eating disorders field: The Academy for Eating Disorders (aedweb.org), Binge Eating Disorder Association (bedaonline.com), Eating Disorder Coalition (eatingdisorderscoalition.org), International Association for Eating Disorder Professionals (iaedp.com), and National Eating Disorder Association (nationaleatingdisorders.org) explicitly support this approach. Civil rights groups including the National Association to Advance Fat Acceptance and the Council on Size and Weight Discrimination also encourage HAES. An international professional organization, the Association for Size Diversity and Health, has developed, composed of individual members across a wide span of professions who are committed to HAES principles.
Several clinical trials comparing HAES to conventional obesity treatment have been conducted. Some investigations were conducted before the name “Health at Every Size” came into common usage; these earlier studies typically used the terms “non-diet” or “intuitive eating” and included an explicit focus on size acceptance (as opposed to weight loss or weight maintenance). A
Pub Med search for “Health at Every Size” or “intuitive eating” or “non-diet” or “nondiet” revealed 57 publications. Randomized controlled trials (RCTs) were vetted from these publications, and additional RCTs were vetted from their references. Only studies with an explicit focus on size acceptance were included.
Evidence from these six RCTs indicates that a HAES approach is associated with statistically and clinically relevant improvements in physiological measures (e.g. blood pressure, blood lipids), health behaviors (e.g. physical activity, eating disorder pathology) and psychosocial outcomes (e.g, mood, self-esteem, body image). All studies indicate significant improvements in psychological and behavioral outcomes; improvements in self-esteem and eating behaviors were particularly noteworthy. Four studies additionally measured metabolic risk factors and three of these studies indicated significant improvement in at least some of these parameters, including blood pressure and blood lipids. No studies found adverse changes in any variables.
Dieting and other weight loss behaviors are popular in the general population and widely encouraged in public health policy and health care practice as a solution for the “problem” of obesity. There is increasing concern about the endemic misrepresentation of evidence in these weight management policies. Researchers have demonstrated ways in which bias and convention interfere with robust scientific reasoning such that obesity research seems to “enjoy special immunity from accepted standards in clinical practice and publishing ethics”. This section discusses the assumptions that underlie the current weight-focused paradigm, presenting evidence that contests their scientific merit and challenges the value of promoting weight management as a public health measure.
Most prospective observational studies suggest that weight loss increases the risk of premature death among obese individuals, even when the weight loss is intentional and the studies are well controlled with regard to known confounding factors, including hazardous behavior and underlying diseases [91-96]. Recent review of NHANES, for example, a nationally representative sample of ethnically diverse people over the age of fifty, shows that mortality increased among those who lost weight.
While many short-term weight loss intervention studies do indicate improvements in health measures, because the weight loss is always accompanied by a change in behavior, it is not known whether or to what extent the improvements can be attributed to the weight loss itself. Liposuction studies that control for behavior change provide additional information about the effects of weight (fat) loss itself. One study which explicitly monitored that there were no changes in diet and activity for 10-12 weeks post abdominal liposuction is a case in point. Participants lost an average of 10.5 kgs but saw no improvements in obesity-associated metabolic abnormalities, including blood pressure, triglycerides, cholesterol, or insulin sensitivity. (Note that liposuction removes subcutaneous fat, not the visceral fat that is more highly associated with disease, and these results should be interpreted carefully.)
In most studies on type 2 diabetes, the improvement in glycemic control is seen within days, before significant weight or fat is lost. Evidence also challenges the assumption that weight loss is associated with improvement in long-term glycemic control, as reflected in HbA1c values. One review of controlled weight-loss studies for people with type 2 diabetes showed that initial improvements were followed by a deterioration back to starting values six to eighteen months after treatment, even when the weight loss was maintained.