Arguments Against Obesity As A Disease #1: BMI Is Not A Good Measure Of Health

Over the past months, I have been involved in countless discussions and debates about whether or not obesity should be considered a chronic disease (as it has by the American and Canadian Medical Associations and a number of other organisations). I therefore thought it perhaps helpful if I discussed each of the common pros and cons on this issue in a series of blog posts. To begin this short series, I’d like to discuss perhaps the most common argument against calling obesity a disease, namely, the well-known shortcomings of BMI. As regular readers will know, I have long railed against the use of BMI as a clinical definition of obesity as it is neither a direct measure of body fatness nor does it directly measure health. In fact, its specificity and sensitivity to pick up health problems commonly associated with obesity (such as type 2 diabetes or hypertension) is so limited, that it would not even remotely meet the criteria commonly applied to other diseases for diagnostic testing. Thus, especially around the BMI cut off of 30 (widely used to “define” obesity in Caucasians), anywhere from 5-25% of individuals would be considered pretty healthy by almost any clinical measure. Even at higher BMI cut offs, it is not all that difficult to find individuals with very mild to non-existent health problems related to their size (as in EOSS 0-1). While some of these individuals may well go on to develop health problems over time, “risk for” a disease is generally not considered a “diagnosis” of that disease. Thus, even if an elevated BMI may indicate increased risk of obesity, it cannot be used to “define” an individual as having the “disease of obesity”. This shortcoming of BMI has been widely (albeit perhaps not widely enough) recognised, which is exactly why, for e.g. the Canadian Medical Association, in their declaration of obesity specifically states that, “BMI is a useful operational definition for obesity but should not be used as the defining characteristic of the disease….in the case of individuals who are very obese, issues of definition and measurement are not relevant.” (emphasis mine) Similarly the WHO in its definition of obesity states that, “BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide because it may not correspond to the same degree of fatness… Read More »

Obesity & Energetic Offerings

For several months now, my colleagues at the University of Alabama have been compiling a weekly list of selected obesity related articles in a list they call Obesity and Energetic Offerings. The list is compiled by David B. Allison, Michelle Bohan-Brown, Emily Dhurandhar, Kathryn Kaiser, and Andrew Brown. The following is this week’s list – the selection are theirs, not mine: Findings Contrary to Hypotheses or Common Beliefs RCT: Calorie menu labeling had no effect on total calories ordered. Click Here The density of healthy food outlets did not predict consumption of fruits or vegetables in NYC. Click Here Densities of supermarkets and other retail outlets are not associated with fruit and vegetable purchases. Click Here Non-monotonic relation of dietary energy density to body composition and growth in pigs. Click Here Are plant-based diets environmentally friendly? Click Here Compared with infants fed formulas, infants fed breast milk had higher fat mass at age 3 months, and lower fat-free mass at age 6-12 months. Click Here Policy-Related Unambiguous Identification of Obesity Trials. Click Here Substitution Patterns Can Limit the Effects of Sugar-Sweetened Beverage Taxes on Obesity. Click Here Sugar-Related RCT: Effects of Caloric and Non-caloric Beverages Consumed Freely at Meal-time on Ad libitum intake. Click Here RCT: Neither HFCS nor table sugar increases liver fat under ‘real world’ conditions. Click Here RCT: Four hypocaloric diets containing different levels of sucrose or high fructose corn syrup do not produce different weight losses.Click Here Basic Science X and Y Chromosome Complement Influence Adiposity and Metabolism in Mice. Click Here The immune system’s involvement in obesity-driven type 2 diabetes. Click Here Accelerated fat cell aging links oxidative stress and insulin resistance in adipocytes. Click Here Asthma drug amlexanox reverses obesity and diabetes in mice. Click Here Children with obese fathers show epigenetic changes that may affect their health. Click Here Chronic treatment with a melanocortin-4 receptor agonist causes weight loss, reduces insulin resistance, and improves cardiovascular function in obese rhesus macaques. Click Here Cycles of protein restriction improved memory and slowed advance of the Alzheimer’s-like disease in mice. Click Here Early Life Nutritional Programming of Obesity: Mother-Child Cohort Studies. Click Here Evidence of Brown Fat Activity in Constitutional Leanness. Click Here Gut Microbiota Helicobacter pylori colonization suppressed weight gain in mice. Click Here RCT: A Mixture of trans-Galactooligosaccharides Reduces Markers of Metabolic Syndrome and Modulates Fecal Microbiota and Immune Function of Overweight Adults. Click… Read More »

Weekend Roundup, Aug 30, 2012

As not everyone may have a chance during the week to read every post, here’s a roundup of last week’s posts: Pulse Grain Consumption Lowers Obesity Risk? What Are Patients Eating One Year After Gastric Banding? 4-6 Months of Exclusive Breast Feeding Associated With Lower Obesity Risk Across 8 European Countries All Obese Patients Should Be Screened For ADHD Training Obesity Specialists from Around the Globe Have a great Sunday! (or what is left of it) AMS Cambridge, UK

Mental Health and Obesity: Day 1

Yesterday, in my talk, at the sold-out standing-room-only Hot Topics Conference on Obesity and Mental Health here in Toronto, I pointed out that individuals presenting with obesity often also present with mental health problems ranging from mood to attention deficit or addiction disorders. In addition, they often have eating disorders, poor self-esteem and body image and other challenges that affect their eating and activity behaviours. Thus, routine assessment and management of mental health problems should be part of obesity management practice. I also presented a brief overview of the Canadian Obesity Network’s 5As of Obesity Management. Roger McIntyre (U of Toronto) presented data showing that individuals with bipolar disorder (BD) are differentially affected by overweight, obesity, and abdominal obesity. The hazards posed by excess weight in the Bd population on illness presentation, clinical course, and outcome have underscored the need to prioritize the prevention and treatment of overweight in this vulnerable population. Emerging evidence indicates that overweight/obesity may adversely affect neurocognitive performance in individuals with BD and may also be inversely associated with other addictive behaviours (e.g. substance use disorders). The contribution of distal adversity (e.g. childhood physical, sexual abuse) as a vulnerability factor for obesity has not been sufficiently reported or characterized. He also presented results from two recently completed studies documenting the effect of obesity on white matter integrity and as well the (positive) impact of bariatric surgery on the course of BD. Randy Sansone (Wright State University, Dayton, Ohio) spoke on the role of borderline personality disorder (an Axis II dysfunction that is characterized by inherent difficulties with self-regulation), which may coexist in syndromes that are characterized by self-regulation difficulties. Perhaps, not surprisingly, studies in various eating disorder samples clearly suggest that restrictive personality styles are associated with restrictive eating pathology whereas impulsive personality styles are associated with impulsive eating pathology. Present data indicate that slightly over one-quarter of obese individuals may suffer from varying degrees of borderline personality disorder. Obviously, this has a number of clinical implications, particularly in terms of assessment, treatment strategies, and outcome. Allan Kaplan (U of Toronto) focussed in his presentation on the fascinating phenomenology and etiology of the two commonest recognized eating disorders, bulimia nervosa and binge eating disorder, and their relationship to obesity. Needless to say, all health professionals dealing with obesity have to be well qualified to recognise and address these eating disorders in their patients and, if necessary,… Read More »

Hot Topics Conference on Obesity and Mental Health, Toronto, June 26-28, 2012

Following a most successful 3rd Canadian Obesity Student Meeting in Edmonton last week, tomorrow sees the start of the Canadian Obesity Network’s Hot Topics Conference on Obesity and Mental Health, organised in partnership with the International Association for the Study of Obesity (IASO) and the Centre for Mental Health and Addiction (CAMH). Attendees will learn about: • Clinical assessment and management of patients with obesity and mental illness • Current evidence and best practices in psychological and behavioural interventions • Current evidence on emerging pharmacological treatments for obesity and mental illness • Current understanding the neuropsychobiology of ingestive behaviour and mental health disorders • Bias and stigma associated with obesity and mental illness • Research priorities in the emerging field of obesity and mental illness. The list of distinguished speakers include: Day 1 (Tuesday, June 26, 13.00-18.00): Opening and Welcome David S. Goldbloom, Chair, Mental Health Commission of Canada Etiological Assessment of obesity and the Role of Mental Health Arya m Sharma, Edmonton, Canada The Neurobiology of Appetite: Hunger as Addiction Alain Dagher, Montreal, Canada Neural Integration of Metabolic, Cognitive, and Emotional Signals in the Control of Ingestive Behavior Hans-Rudolf Berthoud, Baton Rouge, USA A Psychogenetic Analysis of Appetite and Overeating Caroline Davis, Toronto, Canada The Effect of Obesity in Mood Disorders Roger McIntyre, Toronto, Canada ADHD and Obesity Caroline Davis, Toronto, Canada Borderline Personality Disorder and Obesity Randy Sansone, Dayton, USA Binge Eating and Bulimia Allan Kaplan, Toronto, Canada Day 2 (Wednesday, June 27, 8.00-17.30) Stress and Obesity Zul Merali, Ottawa, Canada Gut Hormones for Treating Obesity Nick Finer, London, UK An overview of Current Surgical Treatments for Obesity Teodor Grantcharov, Toronto, Canada Pregnancy and the Post-Partum Period: A Vulnerable Window for Obesity and Mental Illness Valerie Taylor, Toronto, Canada Motivational Interviewing in Bariatric Patients Michael Vallis, Halifax, Canada Psychological and Psychiatric Predictors of Response and Failure to Bariatric Surgery Anthony N Fabricatore, Pennsylvania, USA Behaviour Change for Weight Loss: State of the Science Rohan Ganguli, Toronto, Canada Body Image Across Weight Status Shelly Russell-Mayhew, Calgary, Canada Changing Social Standards Associated with Weight and Body Image Fannie Dagnais, Montreal, Canada Assessing Quality of Life in Obesity Ronette Kolotkin, Durham, USA Perspectives of Persons Living with Obesity: Quality of Life and Engagement in Everyday Life Mary Forhan, Hamilton, Canada Day 3 (Thursday, June 28, 8.00-12.30) Disorders of Consumption: Learnings from Smoking Cessation Peter Selby, Toronto, Canada Preventing Obesity Through Mental… Read More »