What are some of the widespread misconceptions about obesity?

This summary is based on the article published in Canadian Family Physician: Widespread misconceptions about obesity (November 2014)

Jean-Philippe Chaput PhD, Zachary M. Ferraro PhD, Denis Prud’homme MD MSc FRCPC, and Arya M. Sharma MD PhD FRCPC

Related Article of Interest: Addressing the Obesity Epidemic: What Is the Dentist’s Role?

Context

Although obesity can be a serious health threat, there is a lack effective strategies to address this condition on an individual and a societal level. Myths and misconceptions about obesity are pervasive in the media, popular culture, and scientific literature.

As recently discussed in the New England Journal of Medicine, the promulgation of unsupported beliefs might yield poorly informed clinical decisions, inaccurate public health recommendations, and unproductive allocation of limited research resources. 1

Purpose of the Article

Pose a challenge to rethink how we should approach obesity and its management.

Main Points

Obesity is primarily caused by a lack of physical activity or by unhealthy dietary habits.

• There is increasing evidence to support many other putative contributors to the increase in obesity, such as insufficient sleep, psychological stress, endocrine disruptors, medications, intrauterine, and intergenerational effects.
• These nontraditional or new determinants of obesity influence energy input and output; therefore, overeating and reduced energy expenditure are perceived as “symptoms” and not as the root causes of the excess weight. ¹
• An accumulating body of evidence shows that insufficient sleep can impede weight loss and addressing sleep for weight management has recently been endorsed by the Canadian Obesity Network. ²
• More evidence is suggesting that health practitioners and clinicians might need to consider a broader range of influential factors (e.g., medications, lack of time, psychological stress, fatigue, chronic pain) to adequately identify and address the key factors responsible for the patient’s obesity, which is likely a clinical sign of chronic caloric “retention” (similar to edema being a clinical sign of fluid “retention”). ¹

Obese individuals are less active than their normal-weight counterparts.

• The most recent data from the Canadian Health Measures Survey suggest otherwise. Based on objective measures, only 7% of Canadian children and youth ³ and 15% of Canadian adults ⁴ meet physical activity guidelines.
• Overall, the message is that there is a physical inactivity crisis in Canada— most people do not meet the recommended amount of physical activity required each day for health benefits— and every Canadian, regardless of body size, would benefit from an increase in physical activity and a decrease in sitting time.

Diets work in the long term.

• Approximately two-thirds of people who lose weight will regain it within 1 year, and almost all of them will regain it within 5 years. ⁵
• Although dieting (i.e., caloric restriction) to lose weight is a difficult task, the maintenance of lost weight requires the patient to deploy even greater efforts.
• Although sustained weight loss with diet alone can be possible for some individuals, ⁶ agreeing on realistic weight-loss expectations and sustainable behavioural changes is critical to avoid disappointment and non-adherence. Weight regain (relapse) should not be framed as failure but as an expected consequence of dealing with a chronic and complex condition like obesity.

Weight loss does not have significant adverse effects.

• The strong biological response to weight loss (even the recommended 5% to 10% of baseline weight) involves comprehensive, persistent, and redundant adaptations in energy homeostasis that underlie the high recidivism rate of obesity treatment. ⁷
• Among the adverse effects of weight loss, it is well known that body fat loss increases the drive to eat, reduces energy expenditure to a greater extent than predicted, and increases the tendency toward hypoglycemia.17
• Weight loss is also related to psychological stress, increased risk of depressive symptoms, and increased levels of persistent organic pollutants that promote hormone disruption and metabolic complications, all of which are adaptations that substantially increase the risk of weight regain.17
• There is considerable concern about the negative effect of “failed” weight loss attempts on self-esteem, body image, and mental health.18
• Clinicians should document and consider the powerful biological counter-regulatory responses and potential undesired effects of weight loss to maximize the success of their interventions. Obesity is a chronic condition and its management requires realistic and sustainable treatment strategies.

Exercising is better than dieting to lose weight.

• A consistent body of evidence showing that exercise alone, despite a range of health benefits associated with regular exercise, results in rather modest weight loss (less than 2 kg on average). ^{8, 9}
• Individuals who include regular exercise and active living as part of a weight-loss program are more likely to improve their overall health and keep the weight off. ¹⁰
• This latter finding might be attributable to the effect of regular exercise on caloric intake rather than on caloric expenditure per se. ¹¹

Everyone can lose weight with enough willpower.

• The magnitude of weight loss is very different among individuals with the same weight-loss intervention and prescription, and the same compliance to the program—one size does not fit all.
• So, for some people (especially those who have already lost some weight), simply putting more effort into a weight-loss program will not always result in additional weight loss given the different compensatory adaptations to weight loss. 7

A successful obesity management program is measured by the amount of weight lost.

• A growing body of evidence suggests that a focus on weight loss as an indicator of success is not only ineffective at producing thinner, healthier bodies, but could also be damaging, contributing to food and body preoccupation, repeated cycles of weight loss and regain, reduced self-esteem, eating disorders, and social weight stigmatization and discrimination. ¹²
• Obesity management should focus on promoting healthier behaviour rather than simply reducing numbers on the scale.

References

1. Sharma AM, Padwal R. Obesity is a sign—over-eating is a symptom: an aetiological framework for the assessment and management of obesity. Obes Rev 2010; 11(5):362-70. Epub 2009 Nov 17.
2. Chaput JP, Tremblay A. Adequate sleep to improve the treatment of obesity. CMAJ 2012; 184 (18):1975-6. Epub 2012 Sep 17.
3. Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS. Physical activity of Canadian children and youth: accelerometer results from the 2007 to 2009 Canadian Health Measures Survey. Health Rep 2011;22(1):15-23.
4. Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS. Physical activity of Canadian adults: accelerometer results from the 2007 to 2009 Canadian Health Measures Survey. Health Rep 2011;22(1):7-14.
5. Wadden TA. Treatment of obesity by moderate and severe caloric restriction. Results of clinical research trials. Ann Intern Med 1993;119(7 Pt 2):688-93.
6. Franz MJ, VanWormer JJ, Crain AL, Boucher JL, Histon T, Caplan W, et al. Weight-loss outcomes: a systematic review and meta-analysis of weightloss clinical trials with a minimum 1-year follow-up. J Am Diet Assoc 2007;107(10):1755-67.
7. Maclean PS, Bergouignan A, Cornier MA, Jackman MR. Biology’s response to dieting: the impetus for weight regain. Am J Physiol Regul Integr Comp Physiol 2011;301(3):R581-600. Epub 2011 Jun 15.
8. Thorogood A, Mottillo S, Shimony A, Filion KB, Joseph L, Genest J, et al. Isolated aerobic exercise and weight loss: a systematic review and meta-analysis of randomized controlled trials. Am J Med 2011;124(8):747-55.
9. Wing RR. Physical activity in the treatment of the adulthood overweight and obesity: current evidence and research issues. Med Sci Sports Exerc 1999;31(11 Suppl):S547-52.
10. Hill JO, Wyatt HR, Peters JC. Energy balance and obesity. Circulation 2012;126(1):126-32.
11. Chaput JP, Sharma AM. Is physical activity in weight management more about ‘calories in’ than ‘calories out’? Br J Nutr 2011;106(11):1768-9.
12. Bacon L, Aphramor L. Weight science: evaluating the evidence for a paradigm shift. Nutr J 2011;10:9.