In Yet Another Win, Bariatric Surgery Reduces Cancer Risk In Long Term Study

Before you read any further know that I'm NOT a surgeon.

I think it could be fairly argued that as far as surgical impact and benefits go, there are few that rival bariatric surgery.

Shown to prolong life, regularly push many chronic diseases including type 2 diabetes, hypertension, sleep apnea (and so many more) into remission, and dramatically improve subjective quality of life, for so many, bariatric surgery provides a new lease on life.

Well add to the aforementioned list a reduced risk of cancer. While not particularly surprising of course given the relationship between weight and some of our most common cancers, here's new data from the now over 2 decades old SOS study which demonstrates reduced cancer risk in patients who opted for surgery vs. weight matched medically managed controls. 

For those of us who have the good fortune of working with patients who've had bariatric surgery, we know just how life changing it can be. What's shocking though, is the comfort of those who don't work with this category of patients to look down on surgery, or fearmonger about it, and this sadly also includes people in the health care community..

The data is clear. Bariatric surgery is remarkable. That said, I'm hopeful that in 20-30 years, it'll no longer be necessary and will be replaced by medications that lead to surgical degrees of weight loss without the surgery. Until then however, I'm thankful the option of bariatric surgery exists, and if you're not, you're either ignorant or an ideologue.

Every Diet Works For Someone, No Diet Works For Everyone, Diets Are Difficult - IF 2021 Edition

Joining an ever increasing cavalcade of studies of different diets that demonstrate they all work as well or as poorly as one another comes this week's A randomised controlled trial of the 5:2 diet published in PLoS. 

In it researchers randomly assigned 300 participants to receive either:

1) "Standard" brief contact in the form of a 20 minute chat, and the provision of a booklet discussing UK's national dietary guidelines and a leaflet of various local weight management resources, 

2) 20 minutes of Q&A on IF dieting and provision of a leaflet describing 5:2 style intermittent fasting (IF - where two non-consecutive days of the week people are instructed to eat 500-600 calories total), or 

3) That same IF leaflet and chat as above plus 6 weekly one hour group support sessions spread over the first 6 weeks of dieting.

What'd they find?

1) There was no difference in weight loss between groups at 6 months or 1 year post randomization (average loss of just under 4lbs but with some individuals up to 20lbs)

2) Roughly 50% of the participants of each group dropped out within the year

So I guess the same old unsexy conclusion as always. 

Every diet works for someone. No diet works for everyone. Why? Because diets are difficult to sustain unless you happen to enjoy the one you're on.

And to that end, stay far away from healthcare providers claiming there's one best way to lose. Your best diet is someone else's worst.

[Also, if you're able, please consider donating to my #Movember fundraising efforts. It's my one and only annual ask and I'm 80% of the way to my $3,000 goal. No amount is too small, you can give anonymously, and tax receipts are provided. Simply click here to donate, and if you're wondering how it's going, will post an updated picture this Saturday]

2021's Dumbest Scientifically Published Exercise Recommendation For The Treatment Of Obesity

[First written blog post since March 2020. What an awful 20 months. Though the pandemic is certainly not over yet, it feels like it's time to start writing again. Not sure what the frequency of posts will be, but it's nice to be back]

I wouldn't have believed it was real if I hadn't seen this phenomenon so many times before - a research study trying to tie their findings to the treatment of obesity despite the findings being either incapable of leading to clinically meaningful weight loss, or ridiculous to suggest in the first place. Here we've got both.

Published in Cell Reports Medicine, the paper Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men looked at the brown fat stores of Scandinavian men who alternate brief outdoor winter swims with a dash to the sauna 2-3x weekly. 

What'd they find?

The non-randomly selected winter swimmers, all 8 of them, whose average BMIs were 23.7 and whose average age was 25, were found, when exposed to cold, to generate more heat from their brown adipose tissue than their 8 age and weight matched controls. 

How many calories did that brown adipose tissue heat generation burn? If we take their results at face value (their results are orders of magnitude higher than found in a prior study of albeit older subjects), they report that during a "cooling period" of 30 minutes (there was no difference during a "comfort state"), resting energy expenditure was higher in the winter swimmers by an extrapolated 484kcal/24hours. They also reported that winter swimmers spent on average 11 weekly minutes in cold water. So during those 11 minutes the winter swimmers might well be burning 3.7 more calories than their non-winter swimming counterparts - the equivalent number you'd consume eating 1/10th of a carrot. 

The paper is full of various hypotheses to try to tease out the findings from this very small study. 

But what struck me was their final conclusion, 

"Finally, our findings motivate investigations of winter swimming as a lifestyle intervention for increased energy expenditure in obese subjects as a potential weight loss strategy."

Really? Your n=8, non-randomized, observational study of young men without obesity, that didn't control for any weight related variables, which showed that during their 11 minutes of winter-swimming the swimmers might burn 3.7 more calories per week for 4 months than non swimmers motivates investigations of winter swimming as a potential weight loss strategy in people with obesity?

Photo By Jaan Künnap - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=87539864

Canada's Obesity In Adults: A Clinical Practice Guideline, Released Today, A Huge Step Forward

I'm proud to have played a small part in the release of today's Obesity In Adults: A Clinical Practice Guideline as it is the first (I think, though I'm biased) to truly take a patient-centred approach while simultaneously treating obesity like a chronic disease

Not a small endeavour, this years long effort includes chapters never before seen in any other obesity treatment guideline including those on weight bias and stigma, virtual medicine, commercial weight loss programs, living with obesity, as well as issues specific to indigenous peoples.

It explicitly steers away from diet culture (but does speak to the need for individualized medical nutrition therapy), teaches readers that neither BMI nor weight measures the presence or absence of health and introduces them to the concept that obesity should be considered a chronic disease only when excess adiposity impairs health, and it recognizes that obesity is anything but a choice.

While going through the entirety of the guideline isn't doable in a short blog post, here are the guideline's overarching summary points:

• Obesity is a prevalent, complex, progressive and relapsing chronic disease, characterized by abnormal or excessive body fat (adiposity), that impairs health.
• People living with obesity face substantial bias and stigma, which contribute to increased morbidity and mortality independent of weight or body mass index.
• This guideline update reflects substantial advances in the epidemiology, determinants, pathophysiology, assessment, prevention and treatment of obesity, and shifts the focus of obesity management toward improving patient-centred health outcomes, rather than weight loss alone.
• Obesity care should be based on evidence-based principles of chronic disease management, must validate patients’ lived experiences, move beyond simplistic approaches of “eat less, move more,” and address the root drivers of obesity.
• People living with obesity should have access to evidence-informed interventions, including medical nutrition therapy, physical activity, psychological interventions, pharmacotherapy and surgery.

Kudos to all of my fellow authors and especially to Dr. Sean Wharton the project's chief cat wrangler.

To have a peek at the CMAJ's published guideline summary, click here.

To access the guideline in its 19 chapter entirety, click here.

Why Service Provision Fatally Confounds All Diet Studies (5:2 Intermittent Fasting Edition)

Last week I posted about a 5:2 intermittent fasting study that demonstrated terrible adherence with a 58% 5:2 drop out rate by the end of year one and where the average loss was 11lbs.

In response, Erik Arnesen shared another year long 5:2 intermittent fasting vs. continuous energy restriction study where the drop out rate at the end of year one was just 7% and the average loss was 20lbs! (and actually I blogged about this one in the past - tl;dr no difference in outcomes but 5:2 participants were hungrier)

If the diets were identical, why the tremendous difference in adherence and weight loss at a year?

Sure, could be different patient populations, but I'm guessing the much larger factor was the service provision. Because at the end of the day that's a huge part of what's being measured in any organized diet study. Not just in terms of how many visits or touch-points a particular program has, or what collateral materials and support they provide their participants, but also the rapport development, motivational ability, and teaching skills of the service providers themselves.

Having led an inter-professional team for 16 years, I can tell you that who you've got helping your patients/participants has a tremendous impact on their outcomes even within the same program's delivery.

So the next time you consider the outcomes of any study's diet arm, a question worth pondering is how much of those outcomes are consequent to the prescribed diet itself, and how much are consequent to the health care professionals administering it?

Year Long 5:2 Intermittent Fasting Study Reports It's No Better Or Worse Than A Horribly Restrictive Diet

I started out planning to write about a different paper - a one year post intervention followup of people who had completed a prior year of being randomly assigned to 5:2 style intermittent fasting (IF) (2 days a week consuming 400-600 calories) vs. continuous energy restriction (typical of eating less daily) which showed that there was no difference between the two, but when I read it I realized the story was in the initial intervention, not the follow up.

The initial intervention involved randomly assigning 332 people to one of 3 dietary interventions:  Continuous (daily) energy restriction (CER), week-on, week-off energy restriction, and a 5:2 intermittent fasting pattern involving 5 days of habitual intake and 2 very low energy diet days each week.

Of the only 146 completers, no differences were found between the diets in terms of weight loss, adherence, change in lipids, or fasting glucose.

And most of that is consistent with other studies of 5:2 IF which have found that it's no better or worse than any other approach when it comes to weight loss and biochemical changes. But what's not consistent is adherence being the same, wherein other studies tend to see more people quitting IF.

Digging the tiniest bit deeper into this two things stand out. Adherence was abysmal for both CER (49% drop out rate) and IF (58% drop out rate). But what was different here was what was involved in the CER arm. Women randomized to the CER arm were aimed at consuming only 1,000 calories daily for a year, while men were aimed at only 1,200 calories daily. That's a life-suckingly low number of calories for anyone to be aimed at and honestly it surprises me that researchers (and peer reviewers) would think that degree of continuous restriction would be worthy of study.

All this to say, that people were just as likely to report adherence to a misery inducing 1,000-1,200 calorie per day diet as they were to a 5:2 IF approach does not reflect well on the enjoyability (and consequently the broad applicability) of 5:2 style diets.

And for the inevitable trolls, I'm not knocking 5:2 IF. If you love it, terrific! Don't stop! But don't anyone expect it's a panacea for all comers.

Study Published Stating The Daily Mile Doesn't Improve Childhood Obesity Speaks To Risks Of Tying Weight To Exercise

Published this week in the International Journal of Obesity is Effectiveness and cost-effectiveness of The Daily Mile on childhood weight outcomes and wellbeing: a cluster randomised controlled trial whereby researchers reported on the impact a school year worth of 15 minutes of daily running had on children's BMIs.

It's an odd study in that we're talking about 15 minutes of running per day which literally no one should expect to have a marked effect on childhood obesity given both math (15 mins of children running, jogging, or walking a mile probably doesn't even burn the calories of a single Oreo) and the fact that multiple meta-analyses have shown that even far more involved school based PE initiatives don't have an impact on childhood obesity.

It's also odd because The Daily Mile itself doesn't tie itself to weight,

"The aim of The Daily Mile is to improve the physical, social, emotional and mental health and wellbeing of our children – regardless of age, ability or personal circumstances"

And it's a problematic study in that consequent to the wholly predictable non-exciting outcome, it's the sort of study that might be used as a means to discourage the program's continuation.

What might have been studied instead? How about the impact of the Daily Mile on marks, concentration, endurance, or physical literacy (note, they attempted to do some of this, but data collection was too poor for them to make many conclusions), or if there was a strong desire to tie it to something medical, how about blood pressure, heart rate recovery, mood, sleep, or lipid levels?

As I've said many times, dumbing down exercise to weight management shortchanges both the benefits of exercise and the realities of weight management, and frankly doing that in the name of a program that sees kids running an extra 15 minutes a day, and then seeing that published in a credible journal, speaks to just how pervasive and dangerous that practice is.

Should Statistically Significant But Clinically Meaningless Outcomes Still Be Reported As Significant?

Rather than call out the specific paper that led to this blog post (I also don't want to add to its Altmetrics), just a question.

If your systematic review findings demonstrate that a particular supplement/food/diet led to an average total weight loss of 0.7lbs is it appropriate to describe that effect as significant even if statistically you believe you're able to make that claim?

Personally, I don't think so.

Especially not when we're discussing food, because as Kevin Klatt recently pointed out on his blog, there are no food placebos. and as John Ionnidis pointed out, we eat thousands of chemicals in millions of different daily combinations which markedly challenges our ability to conclusively opine about the impact of any one food.

Worse though, is the fact that the media (both traditional and social), won't bother to qualify their enthusiasm when describing these findings and instead will report them as beneficial, significant, and important, as of course will PubMed warriors.

So how to fix this? Perhaps including a qualifying, "but not likely to have any clinical relevance" statement in the abstract might lead to more balanced media coverage (or less media coverage ) which in turn would be less likely to report significant but clinically meaningless outcomes as important, which ultimately would be good for science and scientific literacy.

Product Reformulation Means Sugar Taxes Work Even If People Don't Buy Less As A Consequence

Taxes work to decrease purchasing, and the higher the tax, the greater their impact. Period.

Which is why it's always struck me as odd when people question whether or not sugar-sweetened beverage (SSB) taxes would affect SSB purchases (and consequently consumption).

But let's leave that odd debate aside for a moment. If the goal of SSB taxes is to decrease added sugar consumption (which it explicitly is, while it is explicitly not about weight loss as societal obesity is not singularly caused by SSB consumption, and decreasing SSB consumption is healthy at every weight), it would appear that SSB taxes will decrease sugar consumption even if they don't decrease purchasing.

How?

Because when SSB taxes are enacted, the beverage industry reformulates its products.

And at least according to this bulletin from the World Health Organization, they do so not insignificantly!

Of the 83 products they surveyed in both 2014 (before the UK's SSB tax) and in 2018 (after the UK's SSB tax), the mean sugar content decreased by 42% (from 9.1 g/100mL to 5.3 g/100mL) while the mean energy content decreased by 40% (from 38 kcal/100mL to 23 kcal/100mL). Putting this into the context of a standard 355ml can - that would represent 2.45 fewer teaspoons of sugar and 53 fewer calories per can.

And this was in response to a fairly nominal tax. Presumably larger taxes would drive larger (or more expansive) reformulations which of course would also be coupled with decreased purchasing as has been shown to not at all surprisingly occur where enacted.

All this to say, this is yet another reason why if you're living somewhere without an SSB tax, my bet is that it's a matter of when, not if, you will be.

How Much Do You Like Your Diet? Given Adherence Likely Dependent On Enjoyment, Our Recent Paper Set Out To Quantify That

Back in 2012, I wondered aloud about creating a scoring system for dietary enjoyment. I blogged about it a few times here and there, and happily, a wonderful team of researchers in New Zealand took notice. Now, thanks to the hard work of Michelle Jospe, along with Jillian Haszsard, and Rachel Taylor, the first step towards its formal use has been taken.

Our paper, A tool for assessing the satisfaction of a diet: Development and preliminary validation of the Diet Satisfaction Score, was published late last year and it details our Diet Satisfaction Score's preliminary reliability and validity.

With the help of the 1,604 people (spanning 24 different countries!) who answered our survey questions, as well as 6 diverse experts (thanks to Melanie Dubyk, Kevin Hall, Scott Kahan, Silke Morrison, Marion Nestle, Sherry Pagoto, Arya Sharma and Ethan Weiss), we arrived on the following questions geared to address various aspects of dietary adherence and satisfaction

The simplest way to think of the Diet Satisfaction Score's use is the higher the overall score (each question is answered on a 5 point Likert scale and the final DSS score is calculated by way of taking the mean of all available items yielding a total score between 1 and 5), the greater an individual's satisfaction/enjoyment of that diet is. The hypothesis then would be higher scores correlating with better adherence and consequently better/sustained weight loss.

And that's what our preliminary findings suggest whereby each 1-point higher Diet Satisfaction Score correlated with a 1.7 week longer diet duration. It was also found that compared with those who had abandoned their diets, those maintaining them reported larger losses.

The value of a simple and quick score like this to individuals would be as a means to assess how much (or how little) they were enjoying their diets taking into account more than just whether they like the foods they're eating, but also the impact their chosen diet might be having on related aspects of life (socializing, time, cost, etc.). Those evaluating their new diets and finding their scores low, might explore means to tweak their diets, or to try new ones.

The DSS score's value to clinicians would be as a quick means to screen their patients' efforts and perhaps to use the tool to help trouble shoot, or to triage referrals to professional resources such as registered dietitians.

The value of the DSS score to researchers would be using this tool with shorter term studies as a means to predict whether or not their studied diets are likely to be sustainable (as who really cares how much weight a person might lose on a particular short term diet if few people would actually sustain it).

Of course now what's required is the repeated use of the Diet Satisfaction score in a long-term prospective trial. The good news is that because the tool, like me, is diet agnostic, it can be administered with any and all dietary strategies. Should you be interested in using the Diet Satisfaction Score in your trial Dr. Jospe is the person to contact and her contact information is just this one click away.

Why You Should Probably Just Ignore All Breakfast Studies

By Evan-Amos (Own work) [CC0], via Wikimedia Commons

As has been my tradition, in December I repost old favourites from years gone by. This year am looking back to 2016.

Ugh, breakfast stories.

Such a frustrating topic in nutrition as for both health reporters and diet gurus it would seem that there is no middle ground, breakfast is positioned either as essential or pointless.

Well I'll tell you what's pointless - "breakfast" studies.

I'm putting breakfast in quotations because virtually all the is it good for you or not breakfast studies seem to study breakfast as a whole.

Seems to me that regardless of your chosen end point (be it weight, appetite, hunger, adiposity, heart disease, insulin, school performance, whatever) what a person eats for breakfast will matter a great deal, and just studying whether or not a person ate breakfast, will lump together bowls of Froot Loops with almond topped steel cut oats, and Pop Tarts with summer vegetable omelettes.

My experience, born out of a dozen years of working with thousands of patients on weight management, has been that for most, a protein rich breakfast benefits all-day satiety, whereas a bowl of ultra-processed, sugar-fortified carbs, doesn't. And please note, I said most, not all.

Ultimately breakfast matters for some and not for others, and if you're curious whether or not it's important for you, what you choose to eat for breakfast is going to play a big role in your answer.

And for the love of everything holy, please, please, stop reporting on "breakfast" studies, whether you or they are pro or con, as if they're able to make conclusions about the utility of breakfast as a whole.

#IfYouServeItWeWillEatIt Vegetarian Conference Food Nudge RCT Edition

As I've noted before (usually in the context of soda and junk food) if you serve it, we will eat it, even if the 'we' are a bunch of medical or dietetic professionals.

But what happens if you serve healthier fare? And what happens if you give people a little nudge towards it?

A recent study sought to explore that and prior to 3 conferences, randomized attendees into receiving one of the following two options to consider for their lunch choices

Group 1 (this was the non-vegetarian default ask): At the conference a non-vegetarian buffet will be served for lunch. Please state here if you would like to have a vegetarian dish prepared for you: __________________________________.

Group 2 (this was the vegetarian default ask): At the conference a vegetarian buffet will be served for lunch. Please state here if you would like to have a non-vegetarian dish prepared for you:__________________________________.

You know what happened next.

At all 3 conferences, whatever was highlighted as the default lunch option was chosen by the vast majority for lunch.

At the first conference, the vegetarian choice increased from 2% to 87%. At the second conference it increased from 6% to 86%. And at the third conference it increased from 12.5% to 89%.

You know what would have certainly led to even higher numbers? No non-vegetarian options. And to be clear, I'm not suggesting vegetarian diets are a panacea, there are plenty of unhealthy vegetarian foods, but this simple study illustrates the power afforded to conference organizers in terms of what's being served and how it's being presented to attendees. The same of course would be true of any venue where meals and/or snacks are presented.

Given we eat what we're served, it seems to me to be a straightforward expectation, at least for medical and dietetic conferences, that we're served healthy options.

[Thanks to my friend and colleague David Nunan for sharing this study with me, and you should follow him on Twitter if you don't already]

The Corollary To If You Serve It We Will Eat It (If You Don't, We Won't)

I've written before how as human beings, if you serve it to us, we will eat it, with examples from medical conferences, medical resident events, and dietetic conferences, and published recently in JAMA Internal Medicine is it's corollary, if you don't serve it, we won't eat it, or at least we'll eat it less.

The paper, Association of a Workplace Sales Ban on Sugar-Sweetened Beverages With Employee Consumption of Sugar-Sweetened Beverages and Health explores what happened to sugar-sweetened beverage (SSB) consumption in the 10 months after the University of California at San Francisco banned their sale from campus and medical centre venues (including in their cafeterias, vending machines and retail outlets). People were of course still free to bring whatever beverages they wanted to work or school. Specifically researchers were interested in the impact the sales ban would have on those with heavy SSB intake (defined as a pre-intervention consumption of more than 12 fl oz daily for the prior 3 months).

For two months prior to the intervention, they canvassed for heavy intake participants, and once the SSB sales ban was enacted, half were randomly assigned to receive a 15 minute motivational intervention targeting SSB reduction, half were not, and 10 months later, all of their intakes were again explored.

The findings weren't particularly surprising. When SSBs aren't sold, fewer are consumed.

How much fewer?

Half as much overall, with those receiving the brief motivational intervention seeing their consumption decrease by roughly 75%, and those who didn't by 25% (though it should be noted, especially among those who received the motivational intervention, social desirability bias may have influenced their self-reported consumption reductions).

Bottom line though, it certainly stands to reason that if you don't serve or sell it, we won't eat or drink it, or at the very least, we'll eat or drink much less of it, and so as far as public health interventions go, likely wiser to reduce access to hyperpalatable and indulgent fare rather than simply encouraging people to just eat less of them.

New Systematic Review Concludes No One Will Ever Successfully Maintain Their Lost Weight. Or Does It?

From the Journal I Can't Believe This Ever Got Published (ok, in this case from Obesity Reviews) comes The challenge of keeping it off, a descriptive systematic review of high-quality, follow-up studies of obesity treatments.

The paper apparently is meant to be a counterpoint to other systematic reviews of long term weight loss where,

"conclusions are generally positive and give the impression that weight loss interventions work and that weight loss can be maintained"

Well we can't have that now can we?

It appears these authors sure couldn't because here are the criteria they used in selecting papers for their systematic review that concluded long term weight loss is impossible:

1. Studies must have follow up periods of at least 3 years
2. Patients must not have had any continued interventions during the follow up period
3. Medications approved for weight management aren't allowed

So what they ended up with were 8 studies of varied protocols being administered temporarily for a chronic medical condition where half provided what by definition were only temporary interventions (3 with very low energy diets, and one with hospital provided food). But guess what, chronic medical conditions require ongoing treatment, and what happens when you actually provide it? Well you get studies that would spoil the impossible narrative as noted by the authors of this paper,

"several of the non-included studies report a majority of participants achieving satisfactory weight loss and little regain, especially among studies with continued interventions during the follow-up period."

Imagine that! Appropriately treating a chronic medical condition with continued interventions works!

And this notwithstanding the fact that many (most? all?) of those studies that provided ongoing interventions likely did not include the appropriate prescription of medications to either help with losses or to prevent regain (just as we would with any other chronic condition) because weight loss medications are almost always excluded from use in weight loss diet studies. Which is odd by the way. Consider hypertension for instance. Sure some people might be able to resolve theirs by way of such things as lower sodium diets, increased exercise, and weight loss, but there's zero doubt that patients with hypertension will receive regular ongoing follow up visits with their physicians, and where appropriate, will be prescribed medications to help. Why? Because that's how chronic condition are managed! Which is why we'll never see a systematic review of hypertension treatments demonstrating that brief lifestyle counselling and the explicit exclusion of medications didn't lead to lower blood pressure 3 years later.

Leaving me to wonder, why publish a paper with the literal conclusion,

"that the majority of high-quality follow-up treatment studies of individuals with obesity are not successful in maintaining weight loss over time"

when really all your systematic review (of just 8 papers all with different dietary/lifestyle interventions) has proven is that delimited, lifestyle counselling doesn't miraculously cure a chronic medical problem, and where you admit in your paper that the appropriate provision of ongoing care might well in fact lead to sustained treatment benefits?

But I don't really need to wonder. Because the only reason that this paper was conceived and published is because of weight bias, whereby obesity has different rules applied to it, in this case, the notion that unlike so many other chronic medical conditions that are impacted strongly by lifestyle changes (eg. hypertension, type 2 diabetes, GERD, heart disease, COPD, gout, osteoarthritis, osteoporosis, kidney stones, and many more) people believe that for obesity some brief counselling should be enough to do the job, because that in turn plays into the trope of obesity being a disease of willpower and a deficiency of personal responsibility.

(Thanks to Dr. Andrew Dickson for sending my way)

Thanks to your generosity I'm over 2/3s of the way to my $3,000 Movember fundraising goal. While I'll never monetize this blog, this is my annual fundraiser and if you find value here, consider a donation! Remember, every dollar counts, it's tax deductible, and you can give anonymously! To donate, simply click here

"Severe" Energy Restriction Better For Weight Loss Than "Moderate" Energy Restriction?

Well according to this new RCT it is - in it they found that patients randomly assigned to 4 months of severe energy restriction (65-75% restriction of energy by way of total meal replacement/all liquid diet) followed by 8 months of moderate energy restriction (25-35%), at 12 months, lost significantly more weight than those assigned from the get go to the same degree of moderate energy restriction.

Hurrah?

So first off it's not remotely surprising that putting two groups on the exact same diet (25-35% energy restriction) but starting one group off with 4 months of extreme energy restriction sees those who had the extreme jump start lose more in total.

Secondly, it would appear that the extreme folks have a weight gain trajectory that may well erase the differences over time.

And thirdly, this got me thinking. Behavioural weight loss programs, because they don't involve products (unless medications are being tested, and here they were not), have outcomes that are likely significantly dependent on both material, and perhaps more importantly, on the service providers. Consequently I do wonder about the ability of any of these sorts of studies to be applicable to other offices or programs. Meaning here at least, it would appear the extreme folks did better, and the moderate folks dropped out more often (perhaps consequent to slower than desired initial losses), but would the same necessarily be true at a different site, with the same restrictions but with different service providers, collateral materials, attention and support?

I'd venture those things matter a great deal more than is generally ever mentioned in the medical literature.

And a Movember update! If you enjoy these posts (or even if you don't but you hate read them for something to rage about thereby adding some extra meaning or identity to your life) would love your tax deductible donation to my lipterpillar's growth (and remember, you can give anonymously too). And though I have a family history of prostate cancer (hi Dad!) I think it's important to note that beyond prostate cancer Movember funds multiple men's health initiatives including mental health, suicide, body image, eating disorders, substance use disorders, and testicular cancer. And while I will never charge a penny or host an advertisement on this site, I will, on an annual basis, ask for your donation to this cause. To donate, simply click here

The Journal of Nutrition Describes Gut Bacteria Prevotella Abundance As "The Key To Successful Weight Loss" Following Short Study Where Subjects With No Prevotella Lost Comparable Amount Of Weight

Hype around preliminary findings, animal studies, cell culture studies, underwhelming studies, and more is the clickbait that sells papers and likes. Some of the time hype comes from journalists, sometimes from press-releases, and sometimes from the authors themselves. Today's blog post sees the hype coming from an invited oped published by the American Society of Nutrition's flagship The Journal of Nutrition.

The oped, entitled, The Key to Successful Weight Loss on a High-Fiber Diet May Be in Gut Microbiome Prevotella Abundance, was written in reference to the results of the study entitled, Prevotella Abundance Predicts Weight Loss Success in Healthy, Overweight Adults Consuming a Whole-Grain Diet Ad Libitum: A Post Hoc Analysis of a 6-Wk Randomized Controlled Trial.

The op-ed described the "key" to successful weight loss on a high-fiber diet as gut microbiomes containing an abundance of the bacterium Prevotella, and was written to amplify the - hold onto your hats now - findings from a very small, very short study that was not originally designed to test the relationship between Prevotella abundance and weight, that found a whole 3.5lb greater weight loss among the 15 study subjects with the highest Prevotella abundance vs. the lowest (but still present amount) when consuming a whole grain (WG) diet.

But wait, there's more!

Though it's confusing because of the way they reported weight loss, the same study found that particpants with microbiomes containing no Prevotella also lost weight on a WG diet. In fact, looking at the study's diagram detailing the losses between groups it sure appears as if subjects whose microbiomes contained no Prevotella (0-P) lost statistically comparable amounts of weight as those whose microbiomes contained the most Prevotella (High-P).

So to summarize, people with microbiomes containing what The Journal of Nutrition called, "the key to weight loss on a high-fibre diet" lost pretty much the same amount of weight as people with none of it on a high-fibre diet. Oh, and that key that worked as well as not having a key at all? If we make the enormous leap that it was causal, it led to a 3.48lb weight loss. Whoop whoop?

Bottom line I guess is that if you're going to describe something at the "key" to successful weight loss on a whole grain diet in the title of an op-ed in a prominent journal, and where we're talking about a 4lb weight loss, but having none of that key leads you to lose pretty much the same amount of weight, not only is that not much of a key, but it's incredibly irresponsible as it blatantly contributes to the ongoing erosion of societal scientific literacy and promotes the harmful and erroneous belief that magic exists when it comes to weight loss.

[Also, unless I'm misreading the very small amount of actual data provided, it would seem that the authors of the study also reported the difference between high Prevotella and low Prevotella groups wrong whereby the high group was found to have lost 4lbs (-1.8kg), and the low 0.5lbs (-0.22kg), but rather than report a -1.58kg (3.48lb) difference between the two, they added their losses and reported a -2.02kg (4.45lb) difference.]

Real World Self-Selected Intermittent Fasting (IF) Vs. Continuous Energy Restriction (CER) Study Sees 73% of IF and 61% of CER Participants Not Lasting Even 6 Months

So what happens when you offer people with obesity the choice between 5:2 style intermittent fasting (IF) (very-low calories (VLC) 2 days weekly with 5 days of less restricted eating) and more traditional caloric restriction 7 days a week? Would encouraging people to choose between two strategies increase their likelihoods of successful weight management a year later? Would one group lose more weight than the other? Would adherence be the same?

That were the question post-doc RD Rona Antoni and colleagues set out to explore and they recently published a paper discussing their results.

197 patients with obesity presenting to the Rotherham Institute for Obesity were offered the choice between 5:2 IF (630 calories from liquid meal replacements on the VLC days), or an aimed 500 calorie continuous energy restriction (CER) 7 days per week with diet based off that recommended by the UK's dietary guidelines. Both groups received support from specialist obesity nurses for 6 months and were also asked to return for measurements and discussion at one year. All were also provided with access to, "a variety of specialist facilities, resources and multidisciplinary specialists including exercise and talking therapists", and all were reviewed in clinic monthly where measurements were taken (weight, total body fat, fat-free mass (FFM), waist circumference, systolic and diastolic blood pressure and an overnight fasted blood sample) and adherence was discussed.

99 patients chose IF, and 98 chose CER. 6 months later, 73% of IF patients and 61% of CER patients had dropped out. At one year, 83% of IF and 70% of CER patients were lost to follow up.

Of those who quit IF by 6 months, 18% explicitly reported they did so because they could not tolerate the diet, something that none of the CER drop outs reported, other IF drop outs reported they quit due to fainting or hypoglycemia on VLC days.

Regarding completers' weight losses at 6 months, the IF patients lost a statistically significant, but likely clinically meaningless, 4lbs more than the CER group. All blood measures (including fasting glucose, insulin, hsCRP, and lipids) were found to be the same between groups. Blood pressure changes were also not different between groups.

At one year, the 17 remaining IF patients were found to have regained their lost weight, while the 30 CER patients were found to be maintaining their albeit small amount (3%) of weight loss.

So what to make of this study?

I think the most striking finding was the overall 66% attrition rate across both arms. Certainly this study does not suggest that IF is an easier regime to follow than CER (at least not when provided at the Rotherham Institute for Obesity - given weight management support is a service and not a product, it's certainly possible that different providers might have seen different outcomes for both arms, but I do think this speaks to the challenge of scalability of behavioural interventions). But what I really think this study highlights is the fact that the real-world likelihood of purely dietary interventions treating our increasing weights is very low indeed. Instead, we need more tools for treatment (certainly including medications and surgeries), and more importantly, if we're going to see change, we're going to need environmental level changes to turn this boat around.

As to whether IF or CER will work for you don't forget that one person's horribly restrictive diet is another person's happy lifestyle. If you're trying to find your own right road, even if the first road fails, and even if angry diet gurus and zealots try to tell you there's no other road, keep trying different forks until you find the one that suits you best, as when it comes to diets, adherence is all that matters in the end, and if you don't like the way you're living, you're not likely to keep living that way.

Why You Should Turn Off Your TV And Holster Your Devices Before You Eat

Ok, it's a short study and it relied on dietary recall, but if taken at face value, the results certainly suggest you should be turning off your devices and eating away from the TV.

The study involved the 3 day recall of both diet and media use among 473 individuals.

Plainly, researchers found that meals that were consumed along with some form of media distraction contained 149 more calories. They also found that people consuming those extra calories at a media meal did not compensate by eating less at their next meal.

Given how easy it is to do this, and how by doing so you might even strengthen some interpersonal relationships by eating with friends or family around a table, you really have almost nothing to lose by trying, except perhaps a few calories.

9 Great Suggestions For Improving The Quality Of Dietary Research (And 1 That According To @JamesHeathers Is "Deeply Silly")

Last week saw the publication of an op-ed authored by Drs. David Ludwig, Cara Ebbeling, and Steven Heymsfield entitled, "Improving the Quality of Dietary Research". In it they discuss the many limitations of dietary research and chart a way forward that includes the following 9 great suggestions,

1. Recognize that the design features of phase 3 drug studies are not always feasible or appropriate in nutrition research, and clarify the minimum standards necessary for diet studies to be considered successful.
2. Distinguish among study design categories, including mechanistic, pilot (exploratory), efficacy (explanatory), effectiveness (pragmatic), and translational (with implications for public health and policy). Each of these study types is important for generating knowledge about diet and chronic disease, and some overlap may invariably exist; however, the findings from small-scale, short-term, or low-intensity trials should not be conflated with definitive hypothesis testing.
3. Define diets more precisely when feasible (eg, with quantitative nutrient targets and other parameters, rather than qualitative descriptors such as Mediterranean) to allow for rigorous and reproducible comparisons.
4. Improve the methods for addressing common design challenges, such as how to promote adherence to dietary prescriptions (ie, with feeding studies and more intensive behavioral and environmental intervention), and reduce dropout or loss to follow-up.
5. Develop sensitive and specific biomeasures of adherence (eg, metabolomics), and use available methods when feasible (eg, doubly labeled water method for total energy expenditure).
6. Create and adequately fund local (or regional) cores to enhance research infrastructure.
7. Standardize practices to mitigate the risk of bias related to conflicts of interest in nutrition research, including independent oversight of data management and analysis, as has been done for drug trials.
8. Make databases publicly available at time of study publication to facilitate reanalyses and scholarly dialogue.
9. Establish best practices for media relations to help reduce hyperbole surrounding publication of small, preliminary, or inconclusive research with limited generalizability."

But there is one recommendation that seems at odds with the rest,

Acknowledge that changes to, or discrepancies in, clinical registries of diet trials are commonplace, and update final analysis plans before unmasking random study group assignments and initiating data analysis.

For those who aren't aware, clinical registries are where researchers document in advance the pre-specified methods and outcomes being studied by way of an observational experiment. The purpose of pre-registration is to reduce the risk of bias, selective reporting, and overt p-hacking that can (and has) occurred in dietary research.

Now to be clear, I'm a clinician, not a researcher, and I'm not sure how commonplace changes to or discrepancies in clinical registries of diet trials are, but I'm also not sure that's an argument in their favour even if they are. I do know that recently two of the authors claiming registry changes are commonplace were found to have modified one of their pre-specified statistical analysis plans which if it had been adhered to, would have rendered their results non-significant.

But commonplace or not, is it good science?

To answer that question I turned to James Heathers, a researcher and self-described "data thug" whose area of interest is methodology (and who you should definitely follow on Twitter), who described the notion of accepting that changes and discrepancies to clinical registries were commonplace was, "deeply silly".

He went on to elaborate as to why,

First of all - the whole definition of a theory is something which sets your expectations. the idea that 'reality is messy' does not interfere with the idea that you have hypothesis driven expectations which are derived from theories.

Second: there is nothing to prevent you saying "WE DID NOT FIND WHAT WE EXPECTED TO FIND" and then *following it* with your insightful exploratory analysis. In fact, that would almost be a better exposition of the facts by definition as you are presenting your expectations as expectations, and your after-the-fact speculations likewise.

Third: if you have a power analysis which determines there is a correct amount of observations necessary to reliably observe an effect, having the freedom to go 'never mind that then' is not a good thing by definition.

Fourth: The fact that changes were made is never ever included in the manuscript. i.e. they are proposing being able to make changes to the protocol in the registry *without* having to say so. it's a 'new plan' rather than a 'changed plan'.

Fifth: If you can still do the original analysis then no-one will ever believe that you didn't change the plan after looking at the data. you have to protect yourself, and the best way to do that is to follow your own damned plans and be realistic from the get.

Lastly, Heathers is unimpressed with the argument that registry changes are A-OK because they're commonplace, and he discussed ancient Aztecan punishments for those citing it.

All this to say, there's plenty of room to improve the quality of dietary research. Here's hoping the bulk of these suggestions are taken to heart, but please don't hold your breath.

The Recipe For Aging Gracefully And Adding Life To Your Years

No one wants aging to happen to them, and yet.

While eventually we'll all lose the fight, that doesn't mean we can't go down swinging, and the good news is the recipe for aging without frailty is exceedingly straight forward and was recently spelled out in a systematic review published in the British Journal of General Practice.

The magic formula the 46 included studies pointed to? A mix of regular strength training with regular protein supplementation.

Spelled out a bit further?

20-25 minutes of strength training 4x per week and the purposeful inclusion of protein with every meal and snack (or alternatively, two daily protein supplements providing 25g of protein each).

Though the aforementioned formula won't guarantee a long life, the evidence certainly suggests it'll help to provide a better one adding life to your years if not years to your life.