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Obesity medicine doctor and cynical realist.

Weighty Matters
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April 26, 2012
05:30 AM
92 views

The Biggest Loser Destroys Participants' Metabolisms

by Yoni Freedhoff in Weighty Matters

[This is an updated and edited version of a post originally published in February 2011. I'm updating it as the original post referred simply to a poster presentation but yesterday the full article was published ahead of print in the Journal of Clinical Endocrinology and Metabolism]Talk about setting people up for long term struggle.The term metabolic adaptation is given to the phenomenon whereby when a person loses a certain percentage of weight, their metabolisms slow by greater amounts. This process may be theoretically accelerated with more rapid weight loss as a consequence of the rapidly losing body metabolizing calorie burning muscle along with fat to make up for its massive energy deficit. And as far as rapid non-surgical weight loss goes, there's probably no weight loss program more rapid than that of the television show The Biggest Loser, where it’s not uncommon for contestants to lose upwards of 150lbs at an averaged pace of nearly 10lbs a week. Of course what’s different about the Biggest Loser as compared with most other non-televised rapid weight loss programs is the incredibly large amount of exercise concurrently involved, along with an almost certainly severe degree of stress, peer pressure and dietary restriction given the team and competitive nature of the show (where the team who loses the least weight has a member voted off, and where the last man or woman standing wins $250,000).So is the weight lost on the Biggest Loser, a show now formally endorsed by the First Lady as an inspiration to the nation, healthy? Does the huge amount of exercise protect contestants against the show doing marked damage to their metabolisms?The answer to both of those questions certainly appears to be, "No".In an article published yesterday ahead of print, Darcy Johannsen and friends studied the impact 7 months of Biggest Loser weight loss had on the resting and total energy expenditures of 16 participants. They used all the latest gadgets to do so including indirect calorimetry and doubly labeled water. So what happened? By week 6 participants had lost 13% of their body weight and by week 30, 39%. More importantly by week 6 participants metabolisms had slowed by 244 more calories per day than would have been expected simply as a function of their weight loss and by week 30, by 504 more. That's basically a meal's worth of calories a day that Biggest Loser contestants no longer burn as a direct consequence of their involvement. How do you think you'd do at maintaining your weight if you ate an extra meal a day?But maybe that's typical. After all, metabolic adaptations are a known consequence to weight loss - couldn't that be all we're seeing here? I guess it's too bad there's no control group the study could have used for comparison. Actually there kind of is. Bariatric surgery patients lose massive amounts of weight in a hurry as well, and they generally do so without the inane extremes of lifestyle endorsed by the Biggest Loser. If there were a study on the impact bariatric surgery losses had on resting and total energy expenditure, that would certainly offer some insight as to the healthfulness of Biggest Loser's weight loss program.Good news! There is such a study. Published in 2003 in the American Journal of Clinical Nutrition researchers looked at the impact bariatric surgical losses had on the resting and total energy expenditures of 30 men and women whose pre-operative average BMIs of 50 were within 1 point of the Biggest Loser contestants' averages of 49, and who lost a Biggest Loser style average of 117.5lbs. And guess what? While resting energy expenditure indeed was shown to slow, it didn't slow down in excess of what would be expected by weight loss alone. In other words? Looking at these two studies, Biggest Loser style weight loss destroys metabolisms dramatically more than does bariatric surgery and does so in huge excess of what would be expected simply as a consequence of losing weight (though I suppose to be fair, the study on the surgical patients was done at 14 +/- 2 months, while the Biggest Losers' was at 7 - perhaps the Losers' metabolisms will improve with time)That's a rather ironic finding given that one of the Biggest Loser study's authors, Biggest Loser's TV doctor Dr. Robert Huizenga, regularly trash talks bariatric surgery on the show as a terrifically unhealthy way to lose weight. Metabolically speaking, it would seem to me that his own study would suggest bariatric surgical weight loss is far healthier to a body's metabolism than is Biggest Loser style loss.The study concludes, "Unfortunately, fat free mass preservation did not prevent the slowing of metabolic rate during active weight loss, which may predispose to weight regain unless the participants maintain high levels of physical activity or significant caloric restriction"Gee, ya think? "May"?Here's how I'd spell it out. While some contestants of the Biggest Loser will translate their new lifestyles into careers as product spokespeople or fitness trainers and hence have new external motivators to maintain their extreme behaviours, those who don’t are doomed by the show itself to regain their weight, as the lifestyles promoted by the reality television show The Biggest Loser are only "realistic" to those whose livelihoods and/or fame depend on them.Case in point? That picture up above, that's Eric Chopin. He was the winner of the third season of the Biggest Loser. He lost just over 200lbs. A few years later he was on Oprah to talk about his massive regain. Think Eric dropped the ball? Not me. I think the Biggest Loser provided him with a nonsensical and metabolically dangerous approach to weight management, and in the process, stacked his deck entirely against him.Darcy L. Johannsen, Nicolas D. Knuth, Robert Huizenga, Jennifer C. Rood, Eric Ravussin, & Kevin D. Hall (2012). Metabolic Slowing with Massive Weight Loss despite Preservation of Fat-Free Mass The Journal of Clinical Endocrinology and Metabolism : 10.1210/jc.2012-1444Das SK, Roberts SB, McCrory MA, Hsu LK, Shikora SA, Kehayias JJ, Dallal GE, & Saltzman E (2003). Long-term changes in energy expenditure and body composition after massive weight loss induced by gastric bypass surgery. The American journal of clinical nutrition, 78 (1), 22-30 PMID: 12816767
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Darcy L. Johannsen, Nicolas D. Knuth, Robert Huizenga, Jennifer C. Rood, Eric Ravussin, & Kevin D. Hall. (2012) Metabolic Slowing with Massive Weight Loss despite Preservation of Fat-Free Mass. The Journal of Clinical Endocrinology and Metabolism. info:/10.1210/jc.2012-1444

Das SK, Roberts SB, McCrory MA, Hsu LK, Shikora SA, Kehayias JJ, Dallal GE, & Saltzman E. (2003) Long-term changes in energy expenditure and body composition after massive weight loss induced by gastric bypass surgery. The American journal of clinical nutrition, 78(1), 22-30. PMID: 12816767

April 23, 2012
05:30 AM
48 views

The American Diabetes Association Wants Video Games in Your Kids' School Gyms?

by Yoni Freedhoff in Weighty Matters

A waste of a perfectly good gym?Last week saw a press release from Konami bragging about the involvement of the American Diabetic Association in bringing their exergame Dance, Dance, Revolution to schools across the United States.Demonstrating what I would call a questionable understanding of energy balance, the ADA's Director of Youth Markets Mary Baumann was quoted in the release as stating, "We look forward to the impact the new classroom edition can offer schools to help keep children in the healthy fitness zone for BMIs."Putting aside the fact that I don't actually understand what a "healthy fitness zone for BMIs" is, let's just assume Ms. Baumann was suggesting that kids can Dance, Dance their way to lighter weights.So does Dance, Dance, Revolution actually burn a great many calories?Looking to the medical literature helps. Check out this graph that came from a study published in the journal Pediatrics. It's of the measured energy expenditure of kids at rest and playing Dance, Dance, Revolution.Looks awesome right, kids playing DDR were expending more than double the calories expended at rest. But wait, that's a strange way to report energy expenditure, isn't it? Usually energy expenditure is reported as calories burned per hour of activity, why not here?Because reporting it as a function of energy burned at rest is the only way to make this study sound interesting. When you actually crunch the study's numbers you'll find that DDR helps to burn an additional 91 calories/hr. That's less than half the calories you'd burn leisurely walking, let alone actually running around and playing some sort of sport in a gymnasium.While I've got nothing against exer-gaming, suggesting that it will provide any sort of health benefit, be it weight management, diabetes prevention, or heart health, is more than just wrong and a gross misrepresentation of the medical literature, it's irresponsible. Unfortunately, at this stage of exer-gaming's evolution, they are much more game than they are exercise, and teaching kids, their parents and their educators otherwise, while understandable from video-game developer Konami, is inexcusable from the American Diabetes Association, as this is the exact sort of misinformation that might preclude actually healthy initiatives from being rolled out in schools. [Sadly, it's not just the ADA, today's ridiculousness is also being championed by Let's Move and The National Foundation on Fitness and Sports. Shame on all of them.]Lanningham-Foster, L., Jensen, T., Foster, R., Redmond, A., Walker, B., Heinz, D., & Levine, J. (2006). Energy Expenditure of Sedentary Screen Time Compared With Active Screen Time for Children PEDIATRICS, 118 (6) DOI: 10.1542/peds.2006-1087

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Lanningham-Foster, L., Jensen, T., Foster, R., Redmond, A., Walker, B., Heinz, D., & Levine, J. (2006) Energy Expenditure of Sedentary Screen Time Compared With Active Screen Time for Children. PEDIATRICS, 118(6). DOI: 10.1542/peds.2006-1087

April 12, 2012
05:30 AM
41 views

Justin Sherwood, Refreshments Canada President, Defends Sugar

by Yoni Freedhoff in Weighty Matters

I don't envy the food industry spin doctors their jobs, as at least some of them must realize how ridiculous their arguments are to folks who take the time to critically appraise them.Take for instance Justin Sherwood. Mr. Sherwood is the President of the Canadian Beverage Association and just this week he was tasked with defending sugar as a contributor to obesity, diabetes and heart disease.Let's review Mr. Sherwood's letter, but seen through the lens of Kelly Brownell and Kenneth Warner's Big Tobacco Playbook - whereby they came up with a list of plays that the food industry has co-opted from the early days of the fight to prove tobacco harmful:Focus on personal responsibility as the cause of the nation’s unhealthy diet."The Canadian beverage sector is committed as an industry to providing a variety of products for every lifestyle and occasion through our expanding portfolio of low-and no-calorie beverages, smaller package sizes and through our voluntary, national industry calorie label initiative, Clear on Calories, that provides clear calories information on front of pack to enable informed purchasing decisions and consumption"Raise fears that government action usurps personal freedom.Mr. Sherwood failed to make this play (though he did make it here)Vilify critics with totalitarian language, characterizing them as the food police, leaders of a nanny state, and even “food fascists,” and accuse them of desiring to strip people of their civil liberties.Mr. Sherwood failed to make this play (though he did make it here) Criticize studies that hurt industry as “junk science.”"Contrary to the vast amounts of nutritional science available, the article, based on one controversial study, inaccurately tries to paint the consumption of sugar-sweetened beverages as a direct contributor to obesity, heart disease and diabetes."Emphasize physical activity over diet.Mr. Sherwood failed to make this play (though he did make it here) State there are no good or bad foods; hence no food or food type (soft drinks, fast foods, etc.) should be targeted for change."Research shows that no one single food or beverage can be linked to obesity, and scientific evidence does not support that sugar, in any of its various forms, is a unique cause of any health condition.""No one single food or beverage alone is responsible for people being overweight or obese. All calories count from whatever food or beverage they come from."Plant doubt when concerns are raised about the industry.Mr. Sherwood failed to make this play (though he did make it here)So is Mr. Sherwood right? Is there only a single study out there linking sugared soda as a primary contributor to rising rates of obesity, heart disease and diabetes?Of course not.For a brief summary of literature, here's one from Harvard's Frank Hu.I'm not sure how much money Mr. Sherwood takes home each year but I sure hope it's a great deal. It'd have to be in order to make up for the impact his statements must have on how folks might perceive him as a person.Kelly D. Brownell, & Kenneth E. Warner (2009). Big Tobacco Played Dirty and Millions Died. How Similar Is Big Food? The Milbank Quarterly, 87 (1), 259-294 PMID: 19298423[For those interested, I've posted Mr. Sherwood's remarks below in their entirety as I couldn't seem to find a way to link. They were published in the London Free Press on April 10th, 2012 and a hat tip to blog reader Gay for sending my way]"I read with interest the article, "Sugar can be found in unexpected places (April 9 2012)" in The London Free Press. Contrary to the vast amounts of nutritional science available, the article, based on one controversial study, inaccurately tries to paint the consumption of sugar-sweetened beverages as a direct contributor to obesity, heart disease and diabetes. The Canadian Beverage Association would like to provide scientific facts on the consumption of sugar-sweetened beverages. Research shows that no one single food or beverage can be linked to obesity, and scientific evidence does not support that sugar, in any of its various forms, is a unique cause of any health condition. Statistics Canada's own data indicates that, full calorie soft drink consumption has declined by 30 per cent in the past 11 years but obesity continues to rise-these numbers alone show that there is no link between the two. The international scientific community disagrees with the direct association of sugar consumption as the cause of health issues. For example; & From the Canadian Sugar Institute; "Through scientific reviews such as the Institute of Medicine Dietary Reference Intakes (DRI) report, does not support the view that sugar is "toxic" and a cause of non-communicable diseases"[1] & The Dietitians Association of Australia (DAA) "believes it is simplistic and unhelpful to blame sugar alone for rising obesity rates and other related health problems across the world"[2] & British Nutrition Foundation: "Current evidence does not support the dramatic claims about the association between sugar and health" [3] No one single food or beverage alone is responsible for people being overweight or obese. All calories count from whatever food or beverage they come from. The Canadian beverage sector is committed as an industry to providing a variety of products for every lifestyle and occasion through our expanding portfolio of low-and no-calorie beverages, smaller package sizes and through our voluntary, national industry calorie label initiative, Clear on Calories, that provides clear calories information on front of pack to enable informed purchasing decisions and consumption. "

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Kelly D. Brownell, & Kenneth E. Warner. (2009) Big Tobacco Played Dirty and Millions Died. How Similar Is Big Food?. The Milbank Quarterly, 87(1), 259-294. DOI: 19298423

February 20, 2012
05:30 AM
172 views

After School Sports Increase Junk Food and Total Calorie Consumption

by Yoni Freedhoff in Weighty Matters

That's the conclusion drawn by a recent meta-analysis of the impact of after school sports on pediatric obesity and diet.Weight wise, despite what between the lines reading of the paper suggests the authors wanted to find, they were unable to conclude that after school sports had a beneficial impact on weight status. While there were some studies that suggested benefit, there were many others that did not, leading the authors to ultimately state, "there is not sufficient evidence to conclude that sport participation protects against the development of obesity"So why might that be? After all, it may be fair to assume that kids who play after school sports are more active than kids who don't and consequently burn more calories. In fact according to this review paper, that'd be true in that to date the data would suggest that kids in after school sports are in fact more active overall than kids who aren't (they cite one study that used accelerometry to suggest a 30minute daily difference in physical activity due to organized sport).But if they're burning more calories, why aren't they lighter?Well, if they're burning more but aren't lighter, it'd probably follow they're eating more. And indeed, that's what the research also suggests with extra calories in after school sports participants coming from sugar sweetened beverages (can you say, "Gatorade"?) and from fast food (can you say, "Drive-Thru"?).Now bear in mind the review didn't have that many papers to draw upon, and the results consequently aren't the most robust, but if my patients' and my family's experiences are anything to base things on - many families will hit drive-thrus or take out so as to allow for rapid transit to after school sports and it seems as if a child simply setting food on a blade of grass buys him or her some sort of sugar sweetened treat at game's end.Who said fixing this problem was going to be simple?Nelson TF, Stovitz SD, Thomas M, LaVoi NM, Bauer KW, & Neumark-Sztainer D (2011). Do youth sports prevent pediatric obesity? A systematic review and commentary. Current sports medicine reports, 10 (6), 360-70 PMID: 22071397

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Nelson TF, Stovitz SD, Thomas M, LaVoi NM, Bauer KW, & Neumark-Sztainer D. (2011) Do youth sports prevent pediatric obesity? A systematic review and commentary. Current sports medicine reports, 10(6), 360-70. PMID: 22071397

February 15, 2012
05:30 AM
189 views

This Might Just be the Dumbest "Fitness" Study I've Ever Read!

by Yoni Freedhoff in Weighty Matters

File this under "How could this possibly have been published", along with, "Really. Really?".From the University of Tennessee comes a paper that quantifies the calories burned by adults who while watching an hour of television, were instructed to stand up and step in place during commercial breaks.The results? Apparently you can take around 2,000 steps during an hour of television if you just get up and step on the spot during commercials.My favourite part though has to be the researchers' conclusion,"Because adults are spending more time than ever in front of the TV screen and only a small percentage of American adults engage in adequate amounts (30 min·d-1) of physical activity using standard approaches, we believe that modifying TV-viewing behaviors by having adults step in place during commercial breaks could be useful in promoting physical activity."While I think it's unbelievable that there are at least 3 healthy living researchers out there who think that public health departments and allied health professionals should recommend nonsense as a means to combat obesity or to promote physical activity (because it's complete nonsense to imagine anyone would ever stand up during commercials and step in place on a regular and ongoing basis), what's more unbelievable is that this nonsense also passed peer review.But hey, maybe I'm the crazy one. Maybe this is a phenomenally great idea, and so in that spirit, here are ten other super awesome recommendations of my own:When you go to start your car, instead of just getting in, walk around your car at least 20 times, or better yet - run.When you go to the supermarket, carry, don't push, your cart.While waiting for your meal to arrive in a restaurant do jumping jacks.When reading stories to your children pick your kids up and read to them while walking up and down your stairs.When surfing the net do one burpee every time you navigate to a new webpage.If you do take the elevator, do pushups while it's moving.When you shovel your driveway, first shovel it, then shovel it back onto your driveway, then shovel it off again.Tape your fork and knife to at least 10lb dumbbells so that every bite's a workoutWhen you go through a drive thru, put your car in neutral and push.While waiting in your doctor's office, do wall squats.Who knows, maybe those folks from Tennessee will help to quantify the impact of these oh so helpful suggestions?STEEVES, J., THOMPSON, D., & BASSETT, D. (2012). Energy Cost of Stepping in Place while Watching Television Commercials Medicine & Science in Sports & Exercise, 44 (2), 330-335 DOI: 10.1249/MSS.0b013e31822d797e

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STEEVES, J., THOMPSON, D., & BASSETT, D. (2012) Energy Cost of Stepping in Place while Watching Television Commercials. Medicine , 44(2), 330-335. DOI: 10.1249/MSS.0b013e31822d797e

February 6, 2012
05:30 AM
255 views

Why that Diet Soda/Stroke Paper is Worthless and a Failure of Peer Review

by Yoni Freedhoff in Weighty Matters

Ugh.So without spending too much time on this, here's the thing, that paper that purported daily diet soft drink consumption was associated with several vascular risk factors including strokes? It's useless, and moreover, it's a glaring failure of peer review.Why?Because the authors didn't even attempt to control for dietary quality, and moreover, the dietary recall data itself was obviously inherently flawed.First the control issue. As I'm sure you're aware, what we eat has a tremendous impact upon our risk of developing various chronic diseases. Consequently not accounting for the folks who for instance ate 10 meals a week from fast food restaurants, take aways or diners, versus those who actually ate at home and transformed raw ingredients would likely skew the data. But even if you want to try to suggest that such differences would be accounted for by the dietitians conducting the dietary recall effort, if all you actually analyzed at the end of the day was amounts of consumed protein, carbohydrates and fats, what you'd fail miserably in doing would be to actually usefully compare the quality and caliber of the diets you were studying. By not looking at the quality of the macronutrients you'd be comparing quinoa to white rice, salmon to bacon, and olive oil to Crisco. Yet that's exactly what the authors did. And it's certainly not at all implausible that folks who regularly indulge in lower caliber dietary choices assuage some of their dietary guilt and build their own health halos by choosing a diet beverage over a fully loaded one. But even if the authors accounted for (as they should have at the very least tried) meals out, vs transformed raw ingredients, as well as the actual quality of dietary macronutrients this study would still be useless.Why?Because according to the dietary recall data presented in their study, and despite an average body mass index of 28 (overweight), the self-reported overall caloric intake of the study population was a measly 1,575 calories, whereas 2000 NHANES data pegs the average for men between the ages of 59-79 to be between 2,123-2,590 and women between 1,596 and 1,828. And that's 12 year old NHANES data. Given what we've seen with obesity rates, it's certainly quite plausible if not exceedingly likely, that average caloric consumption has risen over the past decade and change.So basically here we have a study where we know the self-reported dietary recall is inaccurate and where the authors didn't even attempt to account for the actual quality of the participants' diets, that's making conclusions about the impact of diet soft drink consumption on strokes and suggesting diet was a controlled for variable? How this got through peer review is completely beyond me, but the worst part is the coverage. This paper got plenty of press making it's publication not only an embarrassment to the Journal of General Internal Medicine and its peer review process, but also a powerful source of misinformation in a world that certainly doesn't lack for nutritional confusion.Gardener, H., Rundek, T., Markert, M., Wright, C., Elkind, M., & Sacco, R. (2012). Diet Soft Drink Consumption is Associated with an Increased Risk of Vascular Events in the Northern Manhattan Study Journal of General Internal Medicine DOI: 10.1007/s11606-011-1968-2

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Gardener, H., Rundek, T., Markert, M., Wright, C., Elkind, M., & Sacco, R. (2012) Diet Soft Drink Consumption is Associated with an Increased Risk of Vascular Events in the Northern Manhattan Study. Journal of General Internal Medicine. DOI: 10.1007/s11606-011-1968-2

February 1, 2012
05:30 AM
226 views

Obesity in Women Linked to Living Near Parks?!

by Yoni Freedhoff in Weighty Matters

If you like your data clean, pretty and predictable, you probably don't want to read the rest of this post.Researchers from my hometown here in Ottawa recently published a study ahead of print in the journal Obesity. The paper, Relationships Between Neighborhoods, Physical Activity, and Obesity: A Multilevel Analysis of a Large Canadian City looked at a number of different built environment variables and their impacts upon the probability of both leisure time physical activity and overweight and obesity in the population.The statistical models controlled for: Age, education, household income, smoking status, and, given we live in a city where there's a lot of snow, season of data collection. The variables that were considered as potential neighborhood based influencers of physical activity and obesity were: Total bike and walking path length, number of free or minimally expensive indoor and outdoor recreational facilities, park area and green space, social cohesion, neighbourhood safety, number of grocery stores, fast food chains, convenience stores, specialty food stores and full service restaurants.The findings?In men, almost nothing mattered. In fact with weight, nothing at all mattered. Number of fast food joints, convenience stores, grocery stores, park space or recreational facilities - none of these things seemed to impact upon a man's weight. There was however one variable that correlated with increased physical activity. Crime rate. Yup, the more dangerous the neighbourhood, the more active the man, to the tune of a 14% increase in their odds of being physically active for every standard deviation increase in crime rate. Running away from the bad guys?In women? With women for every standard deviation increase in park area they were found to be 17% more likely to be physically active. So far so good, but check this, for every same standard deviation increase in park area women were also 15% more likely to be overweight or obese. In fact the increased risk to overweight and obesity seen with increasing park size in women was only ever so slightly eclipsed by the 17% increased risk conferred to their weights by a standard deviation increase in numbers of convenience stores. The riskiest thing for women's weights according to this paper? Fast food restaurants with a 38% increased risk of weight for every standard deviation increase in those. So what do these numbers mean? So many questions. Should inactive men be encouraged to live in dangerous neighbourhoods? Does nothing in a man's environment really matter to their weights? Should women rethink that new home they're considering beside the park?I don't think so.I think all these numbers mean is that the reasons why people gain weight and exercise, they're stupidly complicated and trying to suss out the impact of a dozen or two different criteria on this sort of ridiculous complexity, might in fact be turn out to be a bit of an exercise in statistically meaningful futility.Prince, S., Kristjansson, E., Russell, K., Billette, J., Sawada, M., Ali, A., Tremblay, M., & Prud'homme, D. (2012). Relationships Between Neighborhoods, Physical Activity, and Obesity: A Multilevel Analysis of a Large Canadian City Obesity DOI: 10.1038/oby.2011.392

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Prince, S., Kristjansson, E., Russell, K., Billette, J., Sawada, M., Ali, A., Tremblay, M., & Prud'homme, D. (2012) Relationships Between Neighborhoods, Physical Activity, and Obesity: A Multilevel Analysis of a Large Canadian City. Obesity. DOI: 10.1038/oby.2011.392

January 18, 2012
05:30 AM
178 views

Gastric Bypasses Destroy Lap-bands in Head to Head Study!

by Yoni Freedhoff in Weighty Matters

While this wasn't a randomized or blinded trial, the results were striking.442 case-matched patients were followed for 6 post-operative years. Half received a gastric bypass, and half a gastric band. While early minor complications were higher in the gastric bypass group (triple the rate seen in banding), major complications were similar. Aside from that, it's all bypass with the bypassed patients enjoying quicker losses, larger maximal losses and significantly better maintenance of losses.How much better?After 6 years, for every failed gastric bypass, there were 4 failed lap bands (with failure determined by BMI greater than 35 or reversal of the procedure). For every 1 long-term bypass complication there were 2 lap band complications, and for every 1 re-operation of a bypassed patient, there were 2 of lap banded ones.Given how damning these results were, the journal invited noted band surgeon Jacques Himpens from Brussels to try to provide some balance in an after article commentary.Dr. Himpens critiques?The study could have used surgeons known to be leading experts in banding and bypass.The mechanistic failing of banding to impact on weight related gut peptides might turn out to be an advantage in the very long term.The band is more readily reversible.Of course Dr. Himpens also clearly stated that he himself agrees gastric bypass is a "better" procedure than gastric banding.Seems like the decision of which surgery to have just became a great deal clearer for those who are considering one.Romy, S., Donadini, A., Giusti, V., & Suter, M. (2012). Roux-en-Y Gastric Bypass vs Gastric Banding for Morbid Obesity: A Case-Matched Study of 442 Patients Archives of Surgery DOI: 10.1001/archsurg.2011.1708

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Romy, S., Donadini, A., Giusti, V., & Suter, M. (2012) Roux-en-Y Gastric Bypass vs Gastric Banding for Morbid Obesity: A Case-Matched Study of 442 Patients. Archives of Surgery. DOI: 10.1001/archsurg.2011.1708

August 25, 2011
05:30 AM
668 views

"Fat Children Eat Less Than Their Thinner Peers"!?

by Yoni Freedhoff in Weighty Matters

"Fat Children Eat Less Than Their Thinner Peers". That's the tweet Linda Bacon from HAES fame sent out to her followers at 9:55am yesterday morning.

It certainly fits the HAES narrative that the world's completely backwards in regard to anything and everything weight related.

Sadly it also continues Linda's confusing practice of tweeting bad data.

Linda's HAES platform, whether you agree or disagree with it, rests on the shoulders of her critical analysis of the medical literature on obesity, and her take is that many of the studies with which researchers and clinicians have vilified obesity, were either poorly designed or poorly analyzed.

But yet here's Linda promoting a Medscape news piece on a non-peer reviewed, poster presentation from a pediatric conference, where the findings are readily debatable.

The poster whose findings she was authoritatively retweeting, tracked the dietary recall of 12,316 children between the ages of 1 and 17 years of age.

Tweet and actual data accuracy aside, what the researchers truly reported wasn't that all fat children eat less than their thinner peers, but rather that the caloric intake of overweight and obese kids aged 1-7 exceeded that of their thinner peers but that the pattern "flipped" at age 7.

So what does "flipped" mean?

According to the poster, 9-11 year old kids with overweight and obesity reported consuming 1,988 calories daily, while their thinner peers reported consuming 2,069 (a difference of 4% which I'd venture isn't likely to be a statistically significant one). The study's 15-17 year olds with overweight and obesity reported consuming 2,271 calories daily, while their thinner counterparts reported 2,537 (a difference of 12%).

But can we really trust the dietary recall of children with overweight and obesity?

I'm not trying to be harsh. This world is not kind to overweight and obese children (or adults), and Linda would certainly know better than most of the stigma, bias and bullying those kids likely face on a daily basis - potentially even from their parents, their schools and their physicians. I don't think it would be an even remotely surprising finding that when participating in dietary recall surveys, children with overweight and obesity, especially older children who've had more time to experience hateful weight bias, might be more likely to under report.

So is there data to suggest that's a real possibility? Could these kids be under-reporting by more than the 12% seen in the oldest age group?

Absolutely.

In fact just this past February there was a review paper published in the International Journal of Pediatric Obesity titled, Assessing dietary intake in children and adolescents: Considerations and recommendations for obesity research. Regarding under-estimation, here's what the review paper's authors had to say, "One of the most robust findings in dietary studies of children and adolescents is the positive association between under reporting and increased body fatness, particularly in adolescents (4,14,15). This is consistent with studies in overweight and obese adults (16). The extent of mis-reporting irrespective of weight status increases with age and has been reported as 14% of energy intake in 6-year-olds (17), 25% in 10-year-olds (18) and 40% (4,19) to 50% (14) in obese adolescents.."The authors further report that the type of study most likely to suffer from under-reporting is the very type performed for the poster in question, "Studies characterising under-reporting have focused on total diet assessment methods and in particular, energy intake"To be clear, I think Linda Bacon's contribution to the field of overweight and obesity research, as well as public policy and attitude, is tremendously important. I just can't rationalize the scientifically critical Linda Bacon with her Twitter persona that seems to just retweet anything that satisfies the HAES narrative, no matter how weak or poorly designed the study (or in this case, the poster) may be.

Sigh.

There's got to be a better way to fight misinformation and statistically indefensible conclusions than the promulgation of misinformation and statistically indefensible conclusions.

Magarey, A., Watson, J., Golley, R., Burrows, T., Sutherland, R., McNaughton, S., Denney-Wilson, E., Campbell, K., & Collins, C. (2011). Assessing dietary intake in children and adolescents: Considerations and recommendations for obesity research International Journal of Pediatric Obesity, 6 (1), 2-11 DOI: 10.3109/17477161003728469

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Magarey, A., Watson, J., Golley, R., Burrows, T., Sutherland, R., McNaughton, S., Denney-Wilson, E., Campbell, K., & Collins, C. (2011) Assessing dietary intake in children and adolescents: Considerations and recommendations for obesity research. International Journal of Pediatric Obesity, 6(1), 2-11. DOI: 10.3109/17477161003728469

August 18, 2011
05:30 AM
692 views

Why are there less "fit and fat" folks than there used to be?

by Yoni Freedhoff in Weighty Matters

That was the question that leaped to mind after looking at one of the appendices of the recent Edmonton Obesity Staging System paper in the CMAJ.

Looking at the graphic up above (if you click it, it'll get larger), it would appear that the earlier NHANES III cohort (1988-1994) included a significantly higher percentage of so-called, "fit and fat" folks, as compared with the later NHANES 1999-2004 cohort.

In the later cohort, the percentage of the study population with an EOSS score of zero (meaning folks with overweight and obesity and no medical or life related co-morbidity) was pretty much zero, whereas in the earlier cohort it would appear that over 15% of overweight folks had an EOSS score of zero, as did just under 10% of folks whose BMIs ranged between 30 and 35 and just over 5% of folks whose BMIs were greater than 35.

Now I'm far from a statistician, but certainly were than any stats savvy folks reading this post, I'd be very curious to know if that differences up above were statistically significant. Given the size of the cohorts and the dramatic differences seen, I'd be surprised if they weren't.

In terms of what's going on?

According to Obesity Panacea's Travis Saunders', one possibility is that the distribution of our weight is changing, and that where we're carrying it is the problem, with increasing abdominal distribution weight-independently increasing our risks of developing a constellation of different chronic diseases.

Travis forwarded me a paper written by Ian Janssen, Margot Shields, Cora L. Craig and Mark S. Tremblay that looked at differences in waist circumferences and 5 skinfold thicknesses for given weights between 1981 and 2009. What they found was that for any given weight, waist circumferences were higher, as were skinfold thickness values.

Their conclusion in the paper seems downright prescient when applied to that graph up above, "These findings suggest that even in the absence of a change in population obesity prevalence as determined by BMI, the population health consequences of obesity seem likely to increase more than anticipated"Given the impact of exercise on distribution of body weight, this definitely lends ammunition to ongoing exercise promotion efforts, and combining that impact along with the results of the second EOSS paper, the one that suggests lifestyle dramatically attenuates EOSS staged risk, and together they would suggest that exercise promotion should take obesity treatment out of the rationale for exercise, and instead focus on exercise/health at any size.

To suss things out further, I'd love to see which weight related co-morbidities increased in the later years cohort - certainly knowing which co-morbidities are on the rise, would help in understanding what exactly's going on.

So whether it's increased abdominal distribution of weight or not, it would certainly seem that there's something else out there, something other than absolute weight, that's increasing morbidity in the population with overweight and obesity. My recommendation is that we redouble our efforts to figure out what that something else is and work on it, as I'm guessing we'll have more luck treating it, than we do treating weight.

Padwal, R., Pajewski, N., Allison, D., & Sharma, A. (2011). Using the Edmonton obesity staging system to predict mortality in a population-representative cohort of people with overweight and obesity Canadian Medical Association Journal DOI: 10.1503/cmaj.110387

Janssen, I., Shields, M., Craig, C., & Tremblay, M. (2011). Changes in the Obesity Phenotype Within Canadian Children and Adults, 1981 to 2007–2009 Obesity DOI: 10.1038/oby.2011.122

Jennifer L. Kuk, Chris I. Ardern, Timothy S. Church, Arya M. Sharma, Raj Padwal, Xuemei Sui, & Steven Blair (2011). Edmonton Obesity Staging System: association with weight history and mortality risk Appl. Physiol. Nutr. Metab., 36, 570-576 : 10.1139/H11-058

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Padwal, R., Pajewski, N., Allison, D., & Sharma, A. (2011) Using the Edmonton obesity staging system to predict mortality in a population-representative cohort of people with overweight and obesity. Canadian Medical Association Journal. DOI: 10.1503/cmaj.110387

Janssen, I., Shields, M., Craig, C., & Tremblay, M. (2011) Changes in the Obesity Phenotype Within Canadian Children and Adults, 1981 to 2007–2009. Obesity. DOI: 10.1038/oby.2011.122

Jennifer L. Kuk, Chris I. Ardern, Timothy S. Church, Arya M. Sharma, Raj Padwal, Xuemei Sui, & Steven Blair. (2011) Edmonton Obesity Staging System: association with weight history and mortality risk. Appl. Physiol. Nutr. Metab., 570-576. info:/10.1139/H11-058

August 11, 2011
05:30 AM
695 views

Did you hear the one about kids who eat candy being thinner?

by Yoni Freedhoff in Weighty Matters

I did.

I heard about it when Linda Bacon from HAES tweeted a link to a press release about it multiple times, calling it "Myth Busting". Knowing that Linda knows how to critically appraise a journal article, I figured it'd be worth reading the actual study.

I was wrong.

The study looked at one solitary day's 24hr. dietary recall collected from 11,182 children between the ages of 2-18 years of age, and then compared candy intake to overweight and obesity status in those same children.

Now dietary recall is known to be fraught with error, especially when it comes to less than healthy foods.

So is there evidence of error here?

Well according to their results, only 30% of children have candy on a daily basis, where candy means a sugar candy or chocolate (more on that in a bit).

That sure sounds like an awfully small number.

And of the kids who actually admitted eating candy, how much were they found to be eating?

One chocolate bar worth for teens aged 14-18 and about 2/3 of a chocolate bar worth for kids aged 2-13.

That sounds like an awfully small number too.

Now maybe kids really don't eat candy any more. Maybe the world's changed more than I've envisioned and only 3 out of 10 children eat candy daily, and do so in rather tempered amounts. And maybe candy's not only not bad for you, but it's good for you, specifically good for you in regard to weight in that this study found that the kids who reported eating candy, were 22 to 26 percent less likely to be overweight or obese!

Of course the other possibility is that it's just an awful study that doesn't fairly lend itself to any conclusion whatsoever (pro or con).

And while we're at the awful study angle, given that this is a study where the authors' conclusion and the public relations spin is that candy's not bad for you, and apparently is protective against overweight and obesity, I think it's probably also worth asking what wasn't counted as candy?

Cookies, freezies, ice-cream, pudding, fruit roll ups, cake, pie, etc. Just chocolate candy and sugar candy. So what else wouldn't fit? Any other junk food - chips, pretzels etc.

Sigh.

The only conclusion I'm able to fairly draw from this study is that those of us who have any degree of Twitter influence, we really have to hold ourselves to a higher standard of retweeting. It's always tempting to retweet a press release or a blog post about a study that fits within our own confirmation biases, but before we do, we should really feel obligated to first read the actual study and evaluate it just as critically as we would those studies that don't fit neatly within our personal narratives.

E. O'Neil, C., L. Fulgoni Iii, V., & A. Nicklas, T. (2011). Association of candy consumption with body weight measures, other health risk factors for cardiovascular disease, and diet quality in US children and adolescents: NHANES 1999–2004 Food & Nutrition Research, 55 DOI: 10.3402/fnr.v55i0.5794

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E. O'Neil, C., L. Fulgoni Iii, V., & A. Nicklas, T. (2011) Association of candy consumption with body weight measures, other health risk factors for cardiovascular disease, and diet quality in US children and adolescents: NHANES 1999–2004. Food . DOI: 10.3402/fnr.v55i0.5794

August 9, 2011
05:30 AM
671 views

Hidden vegetables for one and all!

by Yoni Freedhoff in Weighty Matters

But also don't hide them too!

What am I talking about?

A recent study out of Volumetrics' Barbara Rolls' lab that found incorporating pureed vegetables into 3-5 year olds' bread, pasta sauce, and chicken noodle casserole reduced energy intake in kids by 12%! And don't worry, Dr. Rolls has shown these same type of effects over and over again in adults.

That's not an insignificant, or unexpected reduction - decreasing the energy density of food by adding in piles of pureed vegetables means if you eat the same portion you always eat, you'll consume fewer calories.

You'll also consume more fibre, vitamins and minerals and phytonutrients.

While I do think it's crucial to continually encourage your children (and yourselves) to consume more whole, actual, real, visible, vegetables, there's nothing stopping you from mucking not just with their recipes, but yours too.

So puree to your hearts content, AND don't forget to start with a salad.

[According to Amazon.com, The Sneaky Chef is the highest rated hide the veggies cookbook around]

Spill, M., Birch, L., Roe, L., & Rolls, B. (2011). Hiding vegetables to reduce energy density: an effective strategy to increase children's vegetable intake and reduce energy intake American Journal of Clinical Nutrition DOI: 10.3945/ajcn.111.015206

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Spill, M., Birch, L., Roe, L., & Rolls, B. (2011) Hiding vegetables to reduce energy density: an effective strategy to increase children's vegetable intake and reduce energy intake. American Journal of Clinical Nutrition. DOI: 10.3945/ajcn.111.015206

July 19, 2011
05:30 AM
404 views

Are large amounts of exercise essential for weight loss maintenance?

by Yoni Freedhoff in Weighty Matters

Let me start things off by telling you that I do believe exercise to be extremely helpful in long term weight management. I'll also tell you that I'm a huge fan of the National Weight Control Registry. For those of you who aren't familiar with the Registry, Registrants are folks who are supremely good at maintaining their weight-losses. In fact, the average Registrant has lost 67lbs and kept it off for 5.5 years!There's a great deal of variety in the Registry. Different types of dietary approaches and different strategies as a whole, but there are some commonalities, and exercise is one.Studies on Registrants have their self-reported exercise as being quite high - an average of 58.6 minutes a day!What we didn't have was an objective measurement of same, and sadly, despite a new study with Registrants and accelerometry, I'd argue we still don't, though it seems it wasn't the researchers fault.26 Registrants were recruited to wear accelerometers for a full week and were matched with a never obese group, and an overweight, not Registrant control group. The results were pretty interesting. Measured exercise actually turned out to be significantly less than self reported at 41.5 minutes a day (rather than nearly an hour), but was still of greater duration in Registrants than overweight non-Registrant controls and marginally more than never obese weight-matched controls. But are the results useful? Do they really answer the question as to the importance of exercise in successful weight maintenance?I'm not so sure. The problem I've got with the study's methodology is that Registrants were recruited with a description of the study's aim. Meaning that prior to enrolling they knew they were enrolling themselves in a study that involved objectively measuring their activity levels.To me that's a big deal. It's a big deal because I would imagine that human nature would dictate that the folks who respond to just such a study are the ones who are the most proud of their activity levels (or the least embarrassed depending on how you want to look at it).I suspect too that this was a limitation the authors were aware of as beside the disclosure in the methodology section is the parenthetic explanation, "(as required by our institutional review board)".Another frustration from the study was the fact that individual data points weren't provided. Given the small number of subjects, I would have loved to see the distribution of minutes of exercise - especially given that in their discussion they mention that 2/3 of subjects engaged in >150 minutes weekly, and 1/3 of subjects >300. Did exercise reflect a normal distribution? Was it bimodal? Were there dramatic outliers? Bottom line for me, I'd have loved to see this study performed with a random sample of Registrants, not a sample who may have self-selected for being more active. That's not to say the findings wouldn't necessarily be the same, but given this study's methodology, I wouldn't be hanging my hat on these results. [Also fascinating (though not surprising) was the result that objectively measured exercise was significantly less than self-reported. Furthermore, if my assertion that folks who were better exercisers were more likely to have agreed to enroll, that result casts major doubt on the National Weight Control's finding of massive amounts of exercise being integral to maintenance.]Catenacci VA, Grunwald GK, Ingebrigtsen JP, Jakicic JM, McDermott MD, Phelan S, Wing RR, Hill JO, & Wyatt HR (2011). Physical activity patterns using accelerometry in the national weight control registry. Obesity (Silver Spring, Md.), 19 (6), 1163-70 PMID: 21030947

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Catenacci VA, Grunwald GK, Ingebrigtsen JP, Jakicic JM, McDermott MD, Phelan S, Wing RR, Hill JO, & Wyatt HR. (2011) Physical activity patterns using accelerometry in the national weight control registry. Obesity (Silver Spring, Md.), 19(6), 1163-70. PMID: 21030947

July 11, 2011
05:30 AM
717 views

The American Journal of Clinical Nutrition's recent peer review failure.

by Yoni Freedhoff in Weighty Matters

There's got to be a better way than peer review, because if papers like this one can make it through, the system is broken.The paper's entitled, Dairy attenuates oxidation and inflammatory stress in metabolic syndrome, and it's written by Renee Stancliffe, Teresa Thorpe and Michael Zemel.The paper's aim was to study the impact of dairy on oxidative and inflammatory biomarkers in individuals with metabolic syndrome, following 12 weeks of being randomized to different levels of dietary dairy. They also measured waist circumference.So what's got my feathers ruffled?The whole point of this study was to determine the impact dairy intake had on oxidative stress and inflammation, yet the design of the study had the folks in the "low" dairy group substituting dairy with 3 daily servings of prepackaged non-dairy foods so as to maintain comparable macronutrient intakes between groups.So? Wouldn't ensuring a uniform macronutrient intake be a good idea?Absolutely, but not if the foods you use to ensure uniformity have a known impact on oxidative stress and inflammation! And so what was on the list of foods provided to the low-dairy folks? Among other things processed luncheon meats and trans-fat containing peanut butter crackers.The authors do in fact mention this as a potential confounder in their conclusion, but certainly for me, given that there was no need whatsoever to provide the subjects trans-fat containing foods (there are plenty of trans-fat free cracker choices) or processed meats, it'd have been a peer review deal breaker.Unfortunately, there's more.Waist circumference was also a variable they measured, and they concluded that the higher dairy group significantly reduced their waist circumference and trunk fat. Yet they chose to measure waist circumference, not from an anatomical landmark, but rather from midway between the lateral lower rib margin and the ileac crest at mid-exhalation. While the NHLBI and NIH recommend using an anatomical landmark (the ileac crest), the WHO recommends the midway point described in this paper. However no one recommends mid-exhalation because that's a fairly impossible thing to measure. What this translates to mean is that there was ample room for subjective error, all the more so given that there's no mention of blinding at all in the study methodology.Next there's their description of their diet modalities. They describe their dairy arms as, "low" and "adequate". Adequate is a subjective term. To me, adequate means sufficient, but certainly not ideal. While they might argue they used the term "adequate" because that arm consumed the USDA recommended number of dairy servings, then perhaps they could have used, "USDA recommended" in place of "adequate". Subjective adjectives have no place in a research paper, and it clearly suggests author bias as to the benefits of more dairy.So do the authors have a conflict of interest?Not according to them. The last line of the published paper clearly states, "The authors reported no conflicts of interest" Yet conflicts of interest are almost unavoidable in research. If you're an expert at something, chances are you've benefited from your expertise, and even if you feel that your benefits don't put you into conflict, conflicts of interest must be disclosed if there's a possibility that a person's interests could be even just be fairly perceived as a conflict.So let me ask you, do you think it could fairly be perceived as a conflict of interest to be an author of a study aiming to look at the outcomes of differing degrees of dairy on inflammatory biomarkers and waist circumferences, that's designed with an entirely unnecessarily built in trans-fat containing inflammatory confounder, a lack of blinding, and a subjective means of measuring waist circumference, when you yourself have a patent on the use of dairy to affect fat loss? Or how about if you authored a diet book called, The Calcium Key, where one of your claims was that dairy would, "Triple the rate of fat lost from your abdominal area–the "belly fat" that puts you at greatest risk for high blood pressure, high cholesterol, heart disease, and Type 2 diabetes"If you answer, "yes", then the next question you've got to ask yourself is why Michael Zemel reported no conflicts of interest to the American Journal of Clinical Nutrition, and also just who the heck peer reviewed this paper, as clearly, if they didn't see a conflict with Zemel, then they don't know dairy literature well enough to have been chosen as a peer reviewer.Of course you'd think the editors of the journal ought to have known about the conflict of interest too.Shameful.(of course this isn't the first time Zemel's withheld his conflicts of interest from a journal - see this note published by the editor of the International Journal of Obesity)Stancliffe RA, Thorpe T, & Zemel MB (2011). Dairy attentuates oxidative and inflammatory stress in metabolic syndrome. The American journal of clinical nutrition PMID: 21715516

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Stancliffe RA, Thorpe T, & Zemel MB. (2011) Dairy attentuates oxidative and inflammatory stress in metabolic syndrome. The American journal of clinical nutrition. PMID: 21715516

June 30, 2011
05:30 AM
799 views

Amazing, shocking, unbelievable news about type 2 diabetes and diet!

by Yoni Freedhoff in Weighty Matters

Have you caught the amazing, shocking, unbelievable news that type 2 diabetes can be managed through weight loss and lifestyle change?I sure did.Um, I first caught it in medical school nearly 20 years ago and see it virtually daily in my office. I'm guessing if you've got type 2 diabetes, you caught that news from your doctor. In fact I'd be shocked to learn if there were a single type 2 diabetic on the planet who wasn't told at diagnosis that weight loss and/or lifestyle change could reverse the course of their disease, and while they'd need to maintain their losses/changes to maintain the reversal, that lifestyle can have at least as great an impact on disease course as drugs.So how is it possible that suddenly it's making headline news?,Well you see there was this study that got published in the journal Diabetologia. In it, the authors report that when 11 recently diagnosed, non-insulin dependent, type 2 diabetics were put on a low-carb, 600 calorie diet for 2 months, their diabetes magically disappeared, and that in 7 of them, by adhering to lifestyle/dietary changes, it stayed gone for an additional 3 whole months.Wanna know what else disappeared for the participants?Weight. In the first week they lost nearly 10lbs, or 5% of their presenting body weights. By the end of 8 weeks, they lost nearly 30lbs or 13% of their presenting body weights.So is it surprising that a recently diagnosed type 2 diabetic who loses 30lbs living off an extremely low calorie, low carb diet, can come off of their oral hypoglycemics?About as surprising as a lemon tasting sour.What's perhaps more surprising than the fact that this study was published (small sample size, not even remotely surprising results, and an incredibly extreme and potentially dangerous intervention) was the authors' first line assertion, "Type 2 diabetes is regarded as inevitably progressive, with irreversible beta cell failure"Really? Who regards it that way? Certainly not any doctors I know. Every doctor I know counsels their patients that lifestyle management (weight and/or fitness) can mitigate risk, and in many cases, even reverse the condition.But here's the biggest bee in my bonnet.Studies on extremely low-calorie dieting very clearly state that the vast, vast majority of dieters regain all of the weight they so rapidly lose. We also know that ultra-rapid weight loss leads to disproportionate muscle loss, which in turn may help to explain why folks who lose weight extremely rapidly, when they inevitably head back to their old lifestyles, gain back more weight than they lost. What this means for these study participants, is that there's an extremely real likelihood that they'll not only gain back the 30lbs they lost as participants of this study, but that they'll gain back more. What they'll also almost certainly gain back is their type 2 diabetes, and this time, consequent to their disproportionately lost muscle mass, and their greater than before regain, may well require more, not less, medication to manage their resurgent disease.Ethics should have stopped this study dead in its tracks.Finally, the authors' enthusiastic conclusion about their work?"It carries major implications for information to be given to newly diagnosed patients, who should know that they have a potentially reversible condition and not one that is inevitably progressive"To me anyhow, that demonstrates an incredible lack of perspective, as not only have physicians been counseling their newly diagnosed, type 2 diabetic patients that their condition is potentially reversible with lifestyle change for decades, but the intervention recommended by the authors in this paper is in fact likely to lead to a regain of both weight and type 2 diabetes. Taking this one step further, I'd argue folks who follow these authors' amazing, shocking, unbelievable, major-implications approach, their diabetes will in fact be "inevitably progressive".Where's a good peer reviewer when you need one?Lim, E., Hollingsworth, K., Aribisala, B., Chen, M., Mathers, J., & Taylor, R. (2011). Reversal of type 2 diabetes: normalisation of beta cell function in association with decreased pancreas and liver triacylglycerol Diabetologia DOI: 10.1007/s00125-011-2204-7

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Lim, E., Hollingsworth, K., Aribisala, B., Chen, M., Mathers, J., & Taylor, R. (2011) Reversal of type 2 diabetes: normalisation of beta cell function in association with decreased pancreas and liver triacylglycerol. Diabetologia. DOI: 10.1007/s00125-011-2204-7

June 27, 2011
05:30 AM
764 views

The deleterious impact of snacking on journalistic integrity

by Yoni Freedhoff in Weighty Matters

It's been a bad few weeks for obesity related press releases.The first was that press release from CIHI, where its headline and first paragraph served here in Canada, to lead journalists to declare that all that's necessary to combat obesity are 15 minutes of exercise a day, and a diet rich in fruits and vegetables (and consequently anyone who's obese is lazy and eats Ding Dongs for supper).Now there's this one.It came from the University of North Carolina at Chapel Hill, and it was released in response to the cover story of this month's Obesity medical journal.The press release was entitled, "New Study Highlights Perils of Snack-Filled Diet", and it made quite a splash, working its way through the Twitterverse, which in turn painted "snacking" as a dangerous behaviour for weight management.Of course anyone who reads this blog will know that I'm a huge fan of snacking, and so I quickly clicked away at the links to see if maybe I'm wrong and that I should revamp my approach.So what'd I find?It had pretty much nothing to do with what I'd call, "snacking".The article detailed the weight gain history of male Wistar rats, who for 15 weeks were fed one of 3 different diets: A high fat diet, a low fat diet, or a diet the researchers called the "cafeteria" diet, which in turn consisted of all you can eat chow, superimposed with, "3 human snack foods varied daily". And guess what, rats who were offered unlimited amounts of human "snack" food 3x a day, ate a great deal more calories than their counterparts who were allowed to eat as much boring, unchanging, rat chow as they wanted. Shocker, no? Rats given unlimited access to food almost certainly more palatable than that of their chow-eating counterparts, ate more.But again I've got to come back to the question, what's a snack? After all, the press release has me worried that there are perils to my snack-filled diet.For me a snack might be 25 almonds, or an apple along with an ounce of cheese, or some vegetables and hummus. I strive to have between 150 and 200 calories and a protein source each and every time I snack. So is that what the rats were fed?Nope.Here's the list of foods to which the rats were given unlimited access:Froot Loops, Cocoa Puffs, Little Debbies' Fudge Rounds, peanut butter cookies, Reese's Pieces, Hostess blueberry mini-muffins, Cheez-its, Nestle Crunch bars, nacho cheese Doritos, Keebler Townhouse Butter Crackers, Sugar Wafers, Kroger hot dogs, Kroger cheeses, Wedding Cakes, Frito-Lay Lays Wavy chips, Kroger BBQ pork rinds and Kroger pepperoni slices.So ultimately what this study showed was that caged rats love junk food.Is that news? How this got published as a cover story for the reputable journal Obesity, rather than simply a footnote in the Journal of Duh, is beyond me (though the authors report the physiologic changes in the junk food fed rats mimic human physiologic changes with metabolic syndrome) , but more importantly, the press release out of the University of North Carolina at Chapel Hill, along with last week's from CIHI, has me wondering about the journalistic ethics of press releases, and the responsibilities of institutional PR departments.I know that it's all about the headlines, but snacking, while certainly open to debate as to its utility in weight management (in the vein of multiple small meals vs. three square ones) simply wasn't the subject of this journal article. And in this day and age, where multitudes of people get their information in 140 character sound bites, and at best gloss over full press releases, and rarely if ever click through to actual journal articles, headlines matter even more. Folks reading the University of North Carolina at Chapel Hill's headline will take from it that their plan of healthy between meal snacks is a bad one. Makes me wonder whether or not the rise of Twitter actually puts a greater onus on PR departments to issue non-misleading headlines, even if a truthful one such as, "New Study Highlights the Perils of Unlimited Junk Food Diets", wouldn't garner as many hits.Sampey, B., Vanhoose, A., Winfield, H., Freemerman, A., Muehlbauer, M., Fueger, P., Newgard, C., & Makowski, L. (2011). Cafeteria Diet Is a Robust Model of Human Metabolic Syndrome With Liver and Adipose Inflammation: Comparison to High-Fat Diet Obesity, 19 (6), 1109-1117 DOI: 10.1038/oby.2011.18

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Sampey, B., Vanhoose, A., Winfield, H., Freemerman, A., Muehlbauer, M., Fueger, P., Newgard, C., & Makowski, L. (2011) Cafeteria Diet Is a Robust Model of Human Metabolic Syndrome With Liver and Adipose Inflammation: Comparison to High-Fat Diet. Obesity, 19(6), 1109-1117. DOI: 10.1038/oby.2011.18

June 20, 2011
05:30 AM
830 views

Obesity's contagious, or is it? A sober second look at obesity and social networks.

by Yoni Freedhoff in Weighty Matters

Right off the top let me say I'm not well versed enough in statistics to know who's right.On one side of the fence are the findings of Christakis and Fowler, famously published in the New England Journal of Medicine that posited obesity is socially contagious. Non-statistically, their paper didn't sit right with me, but as far as stats go, I'm no maven.On the other side of the fence is a new paper published by Russel Lyons who posits that Christakis' and Fowler's work is a great example of statistical illiteracy, and that the conclusion drawn from their data, that obesity is socially contagious, is severely flawed and can't be made.Lyons' paper, in a nutshell, gives statistical meat to my gut's firm belief - that shared environments and self-selection may well be explanatory for the clustering of obesity in social networks. That folks whose lifestyles may be more conducive to obesity, may well gravitate towards one another, and/or that people living in geographically/socially similar environments, environments that may contribute to the risk of obesity, together share increased risks and outcomes.Statistical arguments aside (frankly they're way over my head and I couldn't begin to venture a guess who's right and who's wrong), what was most fascinating to me was Lyons' discussion of his paper's publication. If Lyons' hypothesis is correct, his paper's a big deal. It refutes one of the most widely publicized studies of the decade, one that's translated itself into millions of dollars of grants, countless news stories, and even a book that's been published in 20 different languages. So what happened when he tried to publish it? The New England Journal of Medicine and the BMJ rejected it outright, without peer review. JAMA, the Lancet and the Proc. Nat. Acad. Sci. all rejected it next, this time because they have policies of not publishing critiques of articles they themselves didn't publish. Next Lyons submitted his paper to a statistics journal. The journal, Stat. Sci., did send it out for peer review. 2 of the 3 referees recommended publication without revision, and the 3rd, clearly not an obesity researcher, stated that while they agreed with Lyons' conclusions, that the subject was not important enough to warrant publication. Stat. Sci.'s editors agreed with reviewer number 3, and rejected the paper.Eventually Lyons' work was published in the journal Statistics, Politics, and Policy, whose impact factor's rates at 0.857. Contrast that with the impact factor of 50 that the New England Journal of Medicine enjoys.The entire experience has led Lyons to use his paper as a call to action to establish a journal whose subject matter is made up solely of study critiques. Were such a journal available, it would create a venue for publication of important criticisms, further protect the public from bad statistical analyses, and potentially serve as an incentive for researchers to double check their work.All in all, even if you're not a statistician, Lyons' paper is worth a sober read and reflection, and here's something else to chew on - the journalists who were originally all over Christakis' and Fowler's work? I'd bet every last penny I've got that not a single one of them were skilled enough in statistical analysis to analyze it. Really, why should they have been? They're journalists, not statisticians. No, instead they smelled a good story, and ran with it. Those same journalists who shouted from the rooftops that obesity's contagious? I'm betting the vast majority of them are going to be silent on this one, yet wouldn't re-reporting be the socially responsible, ethical, and journalistic right thing to do? Now I know that plenty of reporters read this blog. Would love to hear from you. Am I off base?Lyons, R. (2011). The Spread of Evidence-Poor Medicine via Flawed Social-Network Analysis Statistics, Politics, and Policy, 2 (1) DOI: 10.2202/2151-7509.1024

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Lyons, R. (2011) The Spread of Evidence-Poor Medicine via Flawed Social-Network Analysis. Statistics, Politics, and Policy, 2(1). DOI: 10.2202/2151-7509.1024

May 30, 2011
05:30 AM
751 views

Are we obese 'cause we sit all day long?

by Yoni Freedhoff in Weighty Matters

That was one of the cases put forth by Dr. Bob Ross during our Forks vs. Feet debate.He had discussed an as of then unpublished study that concluded that due to changes in occupation-based physical activity, we were all on average burning 100 fewer calories per workday, and that those no longer burned calories have caused us to become obese.Well, the paper was just published and I had a gander.Now I do think there are weaknesses to the analysis, in that this study of theoretical energy expenditure lost at work doesn't in fact provide a picture of total daily energy expenditure. Meaning that the authors have no idea what the study subjects energy expenditures were like when they weren't working. That's problematic for a few reasons.Firstly it's problematic because it's possible that if you take away 100 calories burned through physical labour, perhaps you'll put them back elsewhere. What I mean to say is that in children we've seen evidence for the existence of an Activitystat whereby kids who exercise more at school do less at home and vice-versa. Given such behaviour has been demonstrated to exist in children, I don't think it's an impossible stretch to wonder if it also occurs in adults, especially since we're talking about just 100 calories per day. And even if it didn't translate to intentional exercise, couldn't more sedentary jobs lead to more fidgeting? More fidgeting would mean more Non-Exercise Activity Thermogenesis. Dr. Levine suggests purposeful NEAT can add up to 500-1000 calories a day, how difficult would an unconscious 100 be?Secondly it's problematic because doubly-labeled water studies suggest that at least between 1983 and 2005, in study populations from Holland and North America, daily energy expenditures haven't changed. Yet in both Holland and North America during that same time period obesity rates have risen dramatically and presumably, we're working progressively cushier jobs.Thirdly it's problematic because in doubly labeled water studies that look at total daily energy expenditure of folks living in developing nations vs. developed nations, for instance subsistence farmers in Nigeria vs. urban Chicagoans, there's been no difference in calories burned, and that total daily calories burned in both populations didn't correlate with weight. I would certainly imagine that being a subsistence farmer in Nigeria would be quite physically demanding work. Lastly, in a massive study of 98 doubly labeled water studies representing 183 cohorts including 14 from countries with low or middle "human development index" (and hence more likely to have physically demanding jobs), again there was no difference in total daily energy expenditures.But even putting aside those concerns, I think the paper's conclusions are telling in regard to the Forks vs. Feet debate.Clearly both forks and feet are thermodynamically implicated in obesity.In one corner, taking this paper to be true (true despite the fact doubly labeled water studies that actually measure total daily energy expenditures suggest otherwise), we've now got 100 calories a day we're not burning due to less physically demanding jobs. In the other corner we've got energy intake data reporting adults are consuming 500 more calories daily now as compared with 1970.Basically we're looking at a 600 calorie surplus. 100 from fitness and 500 from food. Put another way, our modern caloric excess is 83% food and 17% fitness, not exactly a home run for the Feet camp, but damn close the 80/20 rule I tend to believe is true.Church, T., Thomas, D., Tudor-Locke, C., Katzmarzyk, P., Earnest, C., Rodarte, R., Martin, C., Blair, S., & Bouchard, C. (2011). Trends over 5 Decades in U.S. Occupation-Related Physical Activity and Their Associations with Obesity PLoS ONE, 6 (5) DOI: 10.1371/journal.pone.0019657Wilkin, T., Mallam, K., Metcalf, B., Jeffery, A., & Voss, L. (2006). Variation in physical activity lies with the child, not his environment: evidence for an ‘activitystat’ in young children (EarlyBird 16) International Journal of Obesity, 30 (7), 1050-1055 DOI: 10.1038/sj.ijo.0803331Luke, A., Dugas, L., Ebersole, K., Durazo-Arvizu, R., Cao, G., Schoeller, D., Adeyemo, A., Brieger, W., & Cooper, R. (2008). Energy expenditure does not predict weight change in either Nigerian or African American women American Journal of Clinical Nutrition, 89 (1), 169-176 DOI: 10.3945/ajcn.2008.26630Lara R Dugas, Regina Harders, Sarah Merrill, Kara Ebersole, David A Shoham, Elaine C Rush, Felix K Assah, Terrence Forrester, Ramon A Durazo-Arvizu, & Amy Luke (2011). Energy expenditure in adults living in developing compared with industrialized countries: a meta-analysis of doubly labeled water studies The American Journal of Clinical Nutrition, 93 (2), 427-441 : 10.3945/ajcn.110.007278... Read more »

Church, T., Thomas, D., Tudor-Locke, C., Katzmarzyk, P., Earnest, C., Rodarte, R., Martin, C., Blair, S., & Bouchard, C. (2011) Trends over 5 Decades in U.S. Occupation-Related Physical Activity and Their Associations with Obesity. PLoS ONE, 6(5). DOI: 10.1371/journal.pone.0019657

Wilkin, T., Mallam, K., Metcalf, B., Jeffery, A., & Voss, L. (2006) Variation in physical activity lies with the child, not his environment: evidence for an ‘activitystat’ in young children (EarlyBird 16). International Journal of Obesity, 30(7), 1050-1055. DOI: 10.1038/sj.ijo.0803331

Luke, A., Dugas, L., Ebersole, K., Durazo-Arvizu, R., Cao, G., Schoeller, D., Adeyemo, A., Brieger, W., & Cooper, R. (2008) Energy expenditure does not predict weight change in either Nigerian or African American women. American Journal of Clinical Nutrition, 89(1), 169-176. DOI: 10.3945/ajcn.2008.26630

Lara R Dugas, Regina Harders, Sarah Merrill, Kara Ebersole, David A Shoham, Elaine C Rush, Felix K Assah, Terrence Forrester, Ramon A Durazo-Arvizu, & Amy Luke. (2011) Energy expenditure in adults living in developing compared with industrialized countries: a meta-analysis of doubly labeled water studies. The American Journal of Clinical Nutrition, 93(2), 427-441. info:/10.3945/ajcn.110.007278

Westerterp, K., & Speakman, J. (2008) Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. International Journal of Obesity, 32(8), 1256-1263. DOI: 10.1038/ijo.2008.74

Swinburn, B., Sacks, G., & Ravussin, E. (2009) Increased food energy supply is more than sufficient to explain the US epidemic of obesity. American Journal of Clinical Nutrition, 90(6), 1453-1456. DOI: 10.3945/ajcn.2009.28595

May 11, 2011
05:30 AM
760 views

Probiotics for weight management?

by Yoni Freedhoff in Weighty Matters

Very interesting study just came out ahead of print in the American Journal of Clinical Nutrition.In it, researchers studied the impact of over-feeding on stool based calorie loss.Basic principle is that we're not perfectly efficient creatures when it comes to extracting calories from our food. Further, mouse experiments have suggested that their guts' microbial flora and fauna causally impacted their weights. To start exploring this in humans, here researchers studied whether or not changing dietary patterns led to changes in either gut microbiota, or energy lost in stool.The study was a small one. Twelve lean and 9 men with obesity participated. Volunteers were put on a weight maintaining diet for 3 days and then in a random crossover fashion, they consumed either 2400 or 3400 calories for the next 3 days.Ingested and excreted calories were measured by means of bomb calorimetry and gut flora was analyzed microscopically.Interesting result #1?There was no difference initially between the gut microbiota in lean and obese individuals.Fascinating result #2?Changing the nutrient load rapidly changed the bacterial composition of the human gut.Indirectly important result #3?In lean individuals these same changes led to a lesser loss of calories in stool - the more food they were fed, the greater their efficiency at retaining the calories.What does all this mean?Hard to say, these are definitely the early days. No initial difference in gut flora between people who are lean and people who are obese, to me suggests that gut microbiota might not be a big, natural player.Rapidly changing bacterial composition fascinated me because who would have thought you could see dramatic changes so quickly.That those changes actually improved efficiency of calorie absorption in lean individuals is potentially important because it's the opposite of what one might have thought (that one of the protective mechanisms by which perpetually lean folks stay lean might have been less efficient stool absorption), but more importantly, because regardless of the impact being in the wrong direction, it certainly suggests that modifying gut microbiota can in fact dramatically modify the gut's ability to absorb calories - and that in turn might lead one day to yogurts that can actually validly claim that their contents help with weight management.[If you enjoy Weighty Matters you might want to subscribe via email, follow me on Twitter or join the Facebook page]Jumpertz R, Le DS, Turnbaugh PJ, Trinidad C, Bogardus C, Gordon JI, & Krakoff J (2011). Energy-balance studies reveal associations between gut microbes, caloric load, and nutrient absorption in humans. The American journal of clinical nutrition PMID: 21543530

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Jumpertz R, Le DS, Turnbaugh PJ, Trinidad C, Bogardus C, Gordon JI, & Krakoff J. (2011) Energy-balance studies reveal associations between gut microbes, caloric load, and nutrient absorption in humans. The American journal of clinical nutrition. PMID: 21543530

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