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.
To register – click here.
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.
Anyone interested in the issue of obesity and cardiovascular disease may want to get a copy of the latest edition of the Canadian Journal of Cardiology, which includes a number of review articles and opinion pieces on a wide range of issues related to obesity and cardiovascular disease.
Here is the table of contents:
Lim SP, Arasaratnam P, Chow BJ, Beanlands RS, Hessian RC: Obesity and the challenges of noninvasive imaging for the detection of coronary artery disease.
Garcia-Labbé D, Ruka E, Bertrand OF, Voisine P, Costerousse O, Poirier P. Obesity and Coronary Artery Disease: Evaluation and Treatment.
Lovren F, Teoh H, Verma S. Obesity and Atherosclerosis: Mechanistic Insights.
Sankaralingam S, Kim RB, Padwal RS. The Impact of Obesity on the Pharmacology of Medications Used for Cardiovascular Risk Factor Control.
Piché MÈ, Auclair A, Harvey J, Marceau S, Poirier P. How to Choose and Use Bariatric Surgery in 2015.
Poirier P, McCrindle BW, Leiter LA. Obesity-it must not remain the neglected risk factor in cardiology.
Lang JJ, McNeil J, Tremblay MS, Saunders TJ. Sit less, stand more: A randomized point-of-decision prompt intervention to reduce sedentary time.
One of the most common misconceptions in the simplistic “eat less – move more” narrative, is equating the calories in a food with the amount of work that would be needed to burn those calories (e.g. X potato chips equal y minutes of riding your bike).
Not only are things rarely that simple (given that individual “fuel efficiency” varies widely based on size, age, conditioning, fitness, and probably countless other variables), but these messages just serve to reinforce the notion that exercise (or for that matter any form of physical activity) is indeed a viable strategy to “burn off” excess calories.
For what it’s worth, a study by Viera and Antonelli from the University of North Carolina, published in Pediatrics, shows that physical activity calorie equivalent labeling (PACE) has no more impact on parents’ fast food decisions than showing calories only.
The study was conducted as a national survey of 1000 parents randomized to 1 of 4 fast food menus: no labels, calories only, calories plus minutes, or calories plus miles needed to walk to burn the calories.
After excluding implausible answers, the researchers were left with 823 parents, with the mean age of the child for whom the meal was “ordered” being about 9.5 years.
While parents whose menus displayed no calorie label ordered an average of 1294 calories, those those shown calories in any form ordered about 200 calories less, irrespective of whether they were shown calories only, calories plus minutes, or calories plus miles.
Despite this lack of difference, when parents were asked to rate the likelihood each label would influence them to encourage their child to exercise, 20% of parents reported that calories-only labeling would be “very likely” to prompt them to encourage their children to exercise versus 38% for calories plus minutes and 37% for calories plus miles.
From these findings the authors rather enthusiastically conclude that PACE labeling may influence parents’ decisions on what fast food items to order for their children and encourage them to get their children to exercise.
Both of these conclusions are rather optimistic at best.
As for influencing the parents choice, there was clearly no difference between wether or not calories were shown alone or equated to time or miles – calories alone did the job.
And as for whether equating calories to activity would do anything at all in terms of parents actually getting their kids to do more, I would remain rather sceptical till I actually see a study that reliably measures physical activity.
Overall, this study does nothing to alleviate my concerns about equating food calories to calories burnt – this is a narrative that both the food and the fitness industry often favours in their marketing – the former to suggest that with enough physical activity, you can eat as many calories as you want; the latter to suggest that exercising is the best way to lose weight.
I for one would be perfectly happy to just see calories on menus.
According to a study by Thomas Reinehr from the University of Witten/Herdecke, Germany, published in Pediatric Obesity, extremely obese children respond better than extremely obese adolescents to behavioural interventions.
The researchers looked at data from a one-year intensive behavioural intervention 1291 children (mean age 11.0years, mean BMI 27.5, 55.8% female, 37.6% extremely obese (defined by BMI-SDS >2.3) at end of intervention and 1 year later.
While the overall mean BMI-SDS wqs indeed reduced (−0.20 ± 0.32 at end of intervention and −0.14 ± 0.37 1 year later), and there were no significant differences in the outcomes of overweight and obese kids vs. overweight and obese adolescents, this was not the case for the severely obese group.
Here, the group of extremely obese kids (>10 years), showed only a rather modest treatment effect compared to younger extremely obese kids (<10 years).
Thus the authors conclude that,
“Our study demonstrated an encouraging effect of lifestyle intervention in extremely obese children ≤10 years at the end of intervention and 1 year later, but only a limited effect in extremely obese adolescents >10 years.”
This is not unlike the situation for other chronic diseases, where management in adolescents tends to be more challenging than managing younger kids or adults.
I guess this is simply another fact that obesity management shares with the management of other chronic diseases.
If you have experience with managing adolescent obesity, I’d certainly like to hear from you.