City Sewage Predicts Obesity Rates?
And if you thought obesity news could not get quirkier – how about this one? A study by Ryan Newton and colleagues in mBio, the open access journal of the American Society for Microbiology, found that the bacterial composition of city sewage can almost precisely predict obesity rates in that city. The researchers studied the microbial community of sewage from 71 US cities from 31 states using high-througput 165 rRNA gene sequencing technology. Although on average only 15% of bacterial sequences in each sample represented bacteria known to occur in human stool, they were able to capture most (97%) of human fecal oligotypes. Based on the distribution of three primary oligotypes representing different proportions of Bacteroidaceae, Prevotellaceae, or Lachnospiraceae/Ruminococcaceae, the researchers were able to predict whether samples came for cities with high or low prevalence of obesity with 81-89% accuracy. No such relationship was found with non-fecal oligotypes, suggesting that this relationship was indeed due to the representation of human fecal bacteria in the sewage samples. Obviously, it is very possible that the sewage bacterial composition reflects “lifestyles” associated with obesity rather than actual body weights, but the very fact that it was possible to identify important predictive differences in bacterial patterns between cities with varying obesity rates, together with the increasing recognition that gut bacteria may well play a role in obesity (and other metabolic diseases), is fascinating enough. Should these findings be reproducible across other populations, I can only wonder whether sewage sampling may one day serve as a simple way to study changes in nutrition and obesity rates in whole populations. Indeed, I can picture future public health scientists poring over sewage data to check if their public health policies to reduce obesity are in fact working. @DrSharma Edmonton, AB
Patchy Progress on Obesity Prevention – Time To Expand The Food and Activity Paradigm?
In last week’s 2015 Lancet series on obesity, the majority of papers focus on policy interventions to address obesity. It suggests that a reframing of the obesity discussion, that avoids dichotomies (like nature vs. nurture debates) may provide a path forward – both in prevention and management. The policy framework presented by Christina Roberto and colleagues in The Lancet, is based on the NOURISHING framework, proposed by the World Cancer Research Fund International to categorise and describe these actions. Together, the actions in this framework address the food environment (e.g. food availability, taxation, restrictions on advertising, etc.), food systems (e.g. incentives and subsidies for production of healthier foods) and individual behaviour change (e.g through education and counselling). This “food-centric” view of obesity is complemented by recognising that physical activity, much of which is dictated by the built environment and captivity of the population in largely sedentary jobs, also has a role to play. On a positive note, the Christina and colleagues suggest that there may be reasons for careful optimism – apparently 89% of governments now report having units dedicated to the reduction of non-communicable diseases (including obesity), although the size and capacity of many of these units is unknown. On the other hand, despite an increasing number of such efforts over the past decades, no country has yet reversed its epidemice (albeit there is a flattening of obesity growth rates in the lower BMI ranges in some developed countries – with continuing rise in more severe obesity). Despite the potential role of government policies in reducing non-communicable diseases (including obesity) by “nudging” populations towards healthier diets and more physical activity, the authors also note that, “…the reality is that many policy efforts have little support from voters and intended programme participants, and although the passage of policies is crucial, there is also a need to mobilise policy action from the bottom up.” Indeed, there is growing list of examples, where government policies to promote healthy eating have had to be reversed due to lack of acceptance by the public or were simply circumvented by industry and consumers. Nevertheless, there is no doubt that policies in some form or fashion may well be required to improve population health – just how intrusive, costly and effective such measures will prove to be remains to be seen. All of this may change little for people who already have the problem. As the article explains,… Read More »
Early Bird Registration For Canadian Obesity Summit Ends March 3rd
For all my Canadian readers (and any international readers planning to attend), here just a quick reminder that the deadline for early bird discount registration for the upcoming 4th Canadian Obesity Summit in Toronto, April 28 – May 2, ends March 3rd. To anyone who has been at a previous Canadian Summit, attending is certainly a “no-brainer” – for anyone, who hasn’t been, check out these workshops that are only part of the 5-day scientific program – there are also countless plenary sessions and poster presentations – check out the full program here. Workshops: Public Engagement Workshop (By Invitation Only) Pre-Summit Prep Course – Overview of Obesity Management ($50) Achieving Patient‐Centeredness in Obesity Management within Primary Care Settings Obesity in young people with physical disabilities CON-SNP Leadership Workshop: Strengthening CON-SNP from the ground up (Invitation only) Exploring the Interactions Between Physical Well-Being and Obesity Healthy Food Retail: Local public‐private partnerships to improve availability of healthy food in retail settings How Can I Prepare My Patient for Bariatric Surgery? Practical tips from orientation to operating room Intergenerational Determinants of Obesity: From programming to parenting Neighbourhood Walkability and its Relationship with Walking: Does measurement matter? The EPODE Canadian Obesity Forum: Game Changer Achieving and Maintaining Healthy Weight with Every Step Adolescent Bariatric Surgery – Now or Later? Teen and provider perspectives Preventive Care 2020: A workshop to design the ideal experience to engage patients with obesity in preventive healthcare Promoting Healthy Maternal Weights in Pregnancy and Postpartum Rewriting the Script on Weight Management: Interprofessional workshop SciCom-muniCON: Science Communication-Sharing and exchanging knowledge from a variety of vantage points The Canadian Task Force on Preventive Health Care’s guidelines on obesity prevention and management in adults and children in primary care Paediatric Obesity Treatment Workshop (Invitation only) Balanced View: Addressing weight bias and stigma in healthcare Drugs, Drinking and Disordered Eating: Managing challenging cases in bariatric surgery From Mindless to Mindful Waiting: Tools to help the bariatric patient succeed Getting Down to Basics in Designing Effective Programs to Promote Health and Weight Loss Improving Body Image in Our Patients: A key component of weight management Meal Replacements in Obesity Management: A psychosocial and behavioural intervention and/or weight loss tool Type 2 Diabetes in Children and Adolescents: A translational view Weight Bias: What do we know and where can we go from here? Energy Balance in the Weight- Reduced Obese Individual: A biological reality that favours… Read More »
The Lancet’s 2015 Take On Obesity
In 2011, The Lancet dedicated a special issue to the topic of obesity – the general gist being that obesity is a world wide problem which will not be reversed without government leadership and will require a systems approach across multiple sectors. The Lancet also noted that current assumptions about the speed and sustainability of weight loss are wrong. This week, The Lancet again dedicates itself to this topic with ten articles that explore both the prevention and management of obesity. According to Christina Roberto, Assistant Professor of Social and Behavioural Sciences and Nutrition at the Harvard T H Chan School of Public Health and a key figure behind this new Lancet Series, “There has been limited and patchy progress on tackling obesity globally”. Or, as Sabine Kleinert and Richard Horton, note in their accompanying commentary, “While some developed countries have seen an apparent slowing of the rise in obesity prevalence since 2006, no country has reported significant decreases for three decades.” As Kleinert and Horton correctly point out, a huge part of this lack of progress may well be attributable to the increasingly polarised false and unhelpful dichotomies that divide both the experts and the public debate, thereby offering policy makers a perfect excuse for inaction. These dichotomies include: individual blame versus an obesogenic society; obesity as a disease versus sequelae of unrestrained gluttony; obesity as a disability versus the new normal; lack of physical activity as a cause versus overconsumption of unhealthy food and beverages; prevention versus treatment; overnutrition versus undernutrition. I have yet read to read all the articles in this series and will likely be discussing what I find in the coming posts but from what I can tell based on a first glance at the summaries, there appears to be much rehashing of appeals to governments to better control and police the food environments with some acknowledgement that healthcare systems may need to step up to the plate and do their job of providing treatments to people who already have the problem. As much as I commend the authors and The Lancet for this monumental effort, I would be surprised if this new call to action delivers results that are any more compelling that those that followed the 2011 series. I can only hope I am wrong. @DrSharma Edmonton, AB
Are Sedentary Moms Promoting Childhood Obesity?
Last week, Edward Archer from the University of Alabama at Birmingham (UAB), published a paper in the Mayo Clinic Proceedings (to much media fanfare), suggesting that the primary driver of childhood obesity is the shifting of nutrient energy to fetal adipose tissue as a result of increased maternal energy availability paired with decreased maternal energy expenditure, resulting in fetal pancreatic b-cell and adipocyte hyperplasia – a theory, which Edwards labels the “maternal resource hypothesis”. The primary process for these changes, as readers of these pages will have read before, is through epigenetic modification of DNA, which, together with other non-genetic modes of transmission including learned behaviours and environmental exposures (socioenvironmental evolution), leads to “phenotypic evolution”, which Edward describes as, “…a unidirectional, progressive alteration in ontogeny that is propagated over multiple successive generations and may be quantified as the change over time in the population mean for the trait under examination (eg, height and obesity).” Since the beginning of the 20th century, socioevironmental factors have significantly altered the energy balance equation for humans “Socioenvironmental evolution has altered the evolution of human energy metabolism by inducing substantial decrements in EE imposed by daily life while improving both the quality and the quantity of nutrient-energy availability.” “For example, as thermoneutral environments became ubiquitous, the energy cost of thermoregulation declined, and improved sanitation (eg, clean water and safer food) and vaccinations decreased the energy cost of supporting parasites (eg, fleas) and resisting pathogens (eg, communicable diseases and diarrheal infections).” Over the past century, these developments have led to profound phenotypic changes including, “progressive and cumulative increases in height, body stature and mass, birthweight, organ mass, head circumference, fat mass/adiposity as well as decreases in the age at which adolescents attain sexual maturity…” Archer goes on to describe some of the many factors that may have changed in the past century, whereby, he singles out sedentariness as one of the key drivers of these developments (not surprising given Archer’s background in exercise science). Thus, although one could perhaps make very similar arguments for any number of factor that may have changed in the past century to, in turn, affect insulin resistance and ultimately energy partitioning (change in diet, sleep deprivation, increasing maternal age, endocrine disruptors, antibiotic use, gut microbiota, medication use and many other factors I ca think of), Archer chooses to elevate sedentariness to being the main culprit. While this may or may not be the full… Read More »
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