The European Association for the Study of Obesity (EASO) had now released the new OMTF guidelines Practical Recommendations of the Obesity Management Task Force of the European Association for the Study of Obesity for Post-Bariatric Surgery Medical Management.
The guidelines provide the latest guidance on nutritional management, micronutrient supplementation, managing co-morbidities, pharmacotherapy, psychological management, and prevention and management of weight regain. The guidelines also address the issue of post-bariatric surgery pregnancy.
Not covered are issues related to dealing with excess skin and rehabilitation (e.g. return to work, reintegration in social activities, education, etc.), both of significant importance, especially in people with severe obesity.
As the authors note,
“Bariatric surgery is in general safe and effective, but it can cause new clinical problems and it is associated with specific diagnostic, preventive and therapeutic needs. Special knowledge and skills of the clinicians are required in order to deliver appropriate and effective care to the post-bariatric patient. A post-bariatric multidisciplinary follow-up programme should be an integral part of the clinical pathway at centres delivering bariatric surgery, and it should be offered to patients requiring it”
These guidelines are now available open access in Obesity Facts.
As someone who has often engaged in research projects, consultation, or speaking engagements sponsored or otherwise supported by industry (all of which I happily acknowledge and declare), I am a keen observer of the ongoing discussion about when and how researchers need to be wary of potential biases and conflicts.
As I pointed out in previous posts, among all of the potential conflicts, the financial one is perhaps the easiest to declare and otherwise manage.
A recent article by John Ionnadis and John Trepanowski, published in JAMA, discusses the wide range of conflicts (most of which may be non-financial), that one may wish to have declared and exposed, especially when it comes to nutrition research.
The authors single our nutrition research for good reasons:
“…the totality of an individual’s diet has important effects on health, most nutrients and foods individually have ambiguously tiny (or nonexistent) effects. Substantial reliance on observational data for which causal inference is notoriously difficult also limits the clarifying ability of nutrition science. When the data are not clear, opinions and conflicts of interest both financial and nonfinancial may influence research articles, editorials, guidelines, and laws. Therefore, disclosure policies are an important safeguard to help identify potential bias. “
While the potential for financial conflict in relationship to the food industry is well recognised and there are now well-established “disclosure norms”, other conflicts, of which there are many, are not routinely acknowledged, let alone, disclosed.
For one, there are significant financial conflicts that have nothing to do with taking money from industry:
“Many nutrition scientists and experts write books about their opinions and diet preferences. Given the interest of the public in this topic, books about nutrition, diets, and weight loss often appear on best-selling lists, even though most offer little to no evidence to support their frequently bold claims.”
“Financial conflicts of interest can also appear in unexpected places. For example, many not-for-profit nutrition initiatives require considerable donor money to stay solvent. Public visibility through the scientific literature and its reverberation through press releases, other media coverage, and social media magnification can be critical in this regard.”
Even these financial conflicts can perhaps be dealt with through established disclosure norms.
But conflicts can get even more complicated when it starts reflecting researchers’ own personal views and biases::
“Allegiance bias and preference for favorite theories are prevalent across science and can affect any field of study. It is almost unavoidable that a scientist eventually will form some opinion that goes beyond the data, and they should. Scientists are likely to defend their work, their own discoveries, and the theories that they proposed or espoused.”
While that is certainly true for any area of research,
“Nutrition scientists are faced with an additional challenge. Every day they must make numerous choices about what to eat while not allowing those choices to affect their research. Most of them also have been exposed to various dietary norms from their family, culture, or religion. These norms can sometimes be intertwined with core values, absolutist metaphysical beliefs, or both. For instance, could an author who is strongly adherent to some religion conclude that a diet-related prescription of his or her religion is so unhealthy as not to be worthwhile?”
“Advocacy and activism have become larger aspects of the work done by many nutrition researchers, and also should be viewed as conflicts of interest that need to be disclosed. These endeavors often spring from some of the noblest intentions and can lead to invaluable contributions to society and public health in particular. However, advocacy and activism are also orthogonal to a key aspect of the scientific method, which is to not take sides preemptively or based on belief or partisanship. Examples of white-hat bias (bias that distorts scientific evidence in support of a perceived righteous end such as better human health) have been reported.”
The authors therefore propose that,
“…it is important for nutrition researchers to disclose their advocacy or activist work as well as their dietary preferences if any are relevant to what is presented and discussed in their articles. This is even more important for dietary preferences that are specific, circumscribed, and adhered to strongly. For example, readers should know if an author is strongly adherent to a vegan diet, the Atkins diet, a gluten-free diet, a high animal protein diet, specific brands of supplements, and so forth if these dietary choices are discussed in an article. The types of articles in which relevant disclosure should be expected include original research, reviews, and opinion pieces (such as editorials).”
As with financial disclosures,
“Such disclosure should not be seen as an admission of lack of integrity. To the contrary, disclosure strengthens the perceived integrity of the author. Moreover, some disclosures may end up being advantageous depending on future research findings. For example, if at some point strict vegan diets are shown definitively to confer unmatched health benefits, an author who previously disclosed strong adherence to that diet may receive extra recognition and acclaim for his or her prescient wisdom….Availability of these disclosures would allow readers to be either more skeptical or more inspired (depending on how they view the presented evidence and arguments).”
Although the article focuses on nutrition research, the authors acknowledge that similar biases may exist in other areas of research. In my own experience, “ideological biases” (although well-intended) are pervasive through much of the research and publications on topics ranging from physical activity to public health, where I often see strong recommendations made based on evidence that is not even remotely as robust or rigorous as the evidence that comes from, say a large randomised clinical trials of a new prescription drug.
I certainly agree with the authors’ recommendation that,
“As a general rule, if an author’s living example could be reasonably expected to influence how some readers perceive an article, disclosure should be encouraged. Authors who have strong beliefs and make highly committed choices for diet or other behaviors should not hesitate to disclose them. Doing so may help everyone understand who is promoting what and why.”
If there is one article in the 2018 special issue of JAMA on obesity that we could have well done without, it is surely the one by Eve Guth promoting the age-old notion that simply counting calories is a viable and effective means to manage body weight.
As the author suggests:
“It is better for physicians to advise patients to assess and then modify their current eating habits and then reduce their caloric ingestion by counting calories. Counseling patients to do this involves provision of simple handouts detailing the calorie content of common foods, suggested meal plan options, an explanation of a nutrition label, and a list of websites with more detailed information. Patients should be advised that eating about 3500 calories a week in excess of the amount of calories expended results in gaining 1 lb (0.45 kg) of body weight. If a patient reduces caloric ingestion by 500 calories per day for 7 days, she or he would lose about 1 lb of body weight per week, depending on a number of other factors. This is a reasonable and realistic place to start because this approach is easily understood and does not ask a patient to radically change behavior.”
There is so much wrong with this approach, that it is hard to know exactly where to start.
For one, this advise is based on the simplistic assumption that obesity is simply a matter of managing calories to achieve and sustain long-term weight loss.
Not only, do we have ample evidence that these type of approaches rarely result in long-term sustained weight-loss but, more importantly this type of advice comfortably ignores the vast body of scientific literature that tells us that body weight is a tightly regulated physiological variable and that there are a host of complex neuroendocrine responses that will defend our bodies against long-term weight loss – mechanisms that most people (irrespective of whether they have obesity or not) will find it exceedingly hard to overcome with “will-power” alone.
No doubt, caloric “awareness” can be an eye-opener for many patients and there is good evidence that keeping a food journal can positively influence dietary patterns and even reduce “emotional” eating. But the idea that cognitively harnessing “will-power” to count calories (a very “unnatural” behaviour indeed), thereby creating and sustaining a long-term state of caloric deficit is rather optimistic at best.
In fact, legions of people who have been battling obesity all their lives can attest to the fact that encouragement to simply “eat less and move more” (ELMM) as a viable strategy to achieve and sustain significant weight loss is about as effective as reminding people with depression to focus on the brighter side of things and cheer up.
Not to mention the debunked 3500 calorie deficit a week = 1 lb weight loss (week after week after week till a so called “healthy” weight is achieved) myth, which is simply not how bodies work.
Continuing to propagate this antiquated and simplistic idea of what it takes to manage a complex chronic disease like obesity, is exactly what is holding the field back.
There is no reason to assume why more of the same should produce results that are any different from those in the past.
It is time we recognise that restricting caloric intake by willpower alone (irrespective of the dietary strategy) simply does not change the biology of the underlying physiology that effectively defends our bodies against long-term weight loss.
Reading an article like this in 2018 in a reputable journal that promises to “reimagine” obesity is both disappointing and a stark reminder of just how far we have to go to change widely held beliefs that obesity is simply a matter of calories in and calories out – if only life (and human biology) was that simple!
In addition to the series of article on long-term outcomes in bariatric surgery, the 2018 special issue of JAMA on obesity, also features several articles discussing the potential role of taxing or otherwise regulating the use of sugar-sweetened beverages (SSB) as a policy measure to address obesity.
In a first article, Jennifer Pomeranz and colleagues discuss whether or not governments can in fact require health warnings on advertisements for sugar-sweetend beverages. The discussion focuses on an injunction issued by the Ninth Circuit Court on the enforcement of San Francisco’s requirement that sugar-sweetened beverage (SSB) advertisements display a health warning statement, finding that this law likely violated the First Amendment rights of advertisers of SSBs.
The background for this court decision was the fact that San Francisco passed a law requiring SSB advertisers to display: “WARNING: Drinking beverages with added sugar(s) contributes to obesity, diabetes, and tooth decay. This is a message from the City and County of San Francisco.”
In its decision, the court felt that the proposed warning label was not scientifically accurate, as it focussed exclusively on “added sugar(s)” rather than sugars overall. It appears that there is no scientific evidence suggesting that “added sugars” are any more (or less) harmful than the “natural” sugar occurring in any other foods or beverages).
However, as the authors argue, warning on SSB may well be warranted as
“In addition to being a major source of added sugar in the US diet, the liquid form of SSBs could enable rapid consumption and digestion without the same satiety cues as solid foods. SSBs also contain no relevant ingredients to provide offsetting health benefits, in comparison with sweetened whole grain cereals, nut bars, yogurt, or other foods with added sugars, which can have healthful components. Furthermore, the associations of SSBs with weight gain, obesity, type 2 diabetes, and heart disease are each stronger and more consistent than for added sugars in solid foods. In addition, compared with other foods containing added sugars, SSBs are the only source for which randomized controlled trials have confirmed the observational link to weight gain.”
Another point of contention identified by the court was related to the fact that the warning stated harm irrespective of quantity and would have been more accurate had it included the term “overconsumption” or at leas the qualifier “may”.
Here, the authors argue that,
“health risks of SSBs increase monotonically. Thus, use of the word “overconsumption” would not be scientifically accurate because there is no clear threshold effect between SSB consumption and harm. Yet, due to potential individual variation in responses, incorporating the word “may” or “can” would be scientifically accurate and are used in alcohol and smokeless tobacco warnings.”
The third objection by the court was related to the proposed size and rectangular border requirements of the warning, which was considered to be “unduly burdensome” – a point that the authors concede could be dealt with by modify formatting requirements by slightly reducing size, permitting “hairline” borders, or using other methods to ensure prominence and conspicuousness.
.In a second article on the issue of SSBs, Lisa Powell and Matthew Maciejewski discuss the case for taxing SSBs, noting they are the largest contributor of added sugar in the US diet, accounting for approximately 6.5% of total daily calories among adults and 7.3% among youth (ages 2-19 years) and approached 8% to 9% of daily calories among minority populations and 9% to 10% among low-income households. In addition consumption of SSBs have been associated with obesity as well as type 2 diabetes, cardiovascular disease, dental caries, and osteoporosis.
As the authors point out, for SSB taxes to be effective, the increased cost of SSBs has to be passed on to the consumer (“pass-through) and the consumer has to respond by decreasing their consumption (“price elasticity”). In places where SSB taxes have been implemented (e.g. Mexico), both effects have been seen, suggesting that an SSB tax can indeed change consumer behaviours.
However, as the authors also note, so far there is little evidence directly demonstrating that such changes have translated into actual health outcomes (for obesity or otherwise).
Nevertheless, the authors feel that an SSB tax can effectively decrease the overall consumption of these beverages and should perhaps be extended even further to include all forms of sugary drinks including 100% fruit juice. For this approach to be broadly acceptable, it would also be important to dedicate any revenue from these taxes to specific educational or public health purposes.
Finally, a third article on this issue by John Cawley deals with an interesting “quasi experimental” pass-through effect of SSB taxes at the Philadelphia International Airport, which happens to straddle the city border, with some terminals in Philadelphia that are subject to the beverage tax (1.5 cents per ounce), and other terminals in Tinicum that are not.
The study included 31 stores: 21 on the taxed side of the airport (Philadelphia) and 10 on the untaxed side (Tinicum).
As the authors found, following the implementation of the SSB tax in Philadelphia, the average price of SSBs increased on both the taxed and untaxed side of the airport (albeit more so on the taxed side). Using only data for taxed stores, the percentage of the tax passed on to consumers was 93%. Overall, however, the price difference between the taxed and untaxed stores was about 0.83 cents per ounce (a 55% relative pass-through rate).
Thus, while the tax did have a significant effect on SSB pricing in Philadelphia, it appears that the non-taxed stores simply went along to increase their profit margins accordingly.
Whether or not these changes in pricing had any impact on actual SSB sales or consumption was not reported.
Together, these studies certainly support the statement by Powell and Maciejewski that
“SSB taxes are likely to remain controversial for some time and policy makers will have a number of issues to consider as they formulate and implement fiscal policies.”
“SSB taxation can only be one approach to what must be a multipronged public health strategy to reduce obesity via improved diets and increased activity. The fact that intake of SSBs has declined over the past decade and the obesity epidemic has continued unabated suggests that reducing SSBs alone is not the sole solution. Adults and youth who frequently consume SSBs are more likely to engage in other unhealthy behaviors (eg, inactivity, greater fast-food consumption), so population-based policies specifically targeting these behaviors need to be designed in concert with SSB taxes. Although SSB consumption remains high in the United States, particularly among vulnerable populations, and taxation is a viable tool for curbing its consumption, the long-run intended and unintended effects of SSB tax policy are yet to be determined. The debate on its merits as an effective tool to improve health outcomes will be greatly informed by rigorous evidence on consumption, sugar intake, and body weight both on average and within vulnerable populations (children, minorities, low-income individuals).”
There is no reasonable argument against the fact that excess weight gain is one of the key drivers of diabetes risk, and it should come as no surprise to anyone, that losing weight (though bariatric surgery or otherwise) dramatically improves glycemic control in people living with type 2 diabetes.
So what exactly can we learn from the DIRECT study published by Michael Lean and colleagues in The Lancet?
For one, this is a large cluster-randomised trial of obesity intervention conducted entirely in a non-specialist primary care setting with significant weight loss (at least 15 Kg) and diabetes remission (defined as glycated haemoglobin (HbA1c) of less than 6·5% after at least 2 months off all antidiabetic medications) as the pre-defined primary outcome at 12 months.
In the intervention centres, a nurse or dietitian (as available locally) was given a total of 8 h structured training by the study research dietitians experienced in the Counterweight-Plus program.
Initial weight loss was induced with a total diet replacement phase using a low energy formula diet (825–853 kcal/day) for 3 months (extendable up to 5 months if wished by participant), followed by structured food reintroduction of 2–8 weeks (about 50% carbohydrate, 35% total fat, and 15% protein), and an ongoing structured programme with monthly visits for long-term weight loss maintenance.
Given the primary care non-specialist setting of this trial, the key findings (as summarized by the authors), were perhaps surprising:
“Just less than a quarter of participants in the intervention group achieved weight loss of 15 kg or more at 12 months, half maintained more than 10 kg loss, and almost half had remission of diabetes, off antidiabetic medication….Remission was closely related to the degree of weight loss maintained at 12 months, with achievement in 86% of participants with at least 15 kg weight loss, and 73% of those with weight loss of 10 kg or more. 28% of all eligible individuals volunteered to participate,17 and 79% completed the intensive total diet replacement phase…”
In general, the intervention was well tolerated with 117 out of 150 participants (78%) in the intervention group completing the intervention.
So here are the key learning from DIRECT:
For one, there should no longer be any doubt that “remission” of Type 2 diabetes is possible in a substantial number of patients, if we can help them achieve and sustain significant weight loss – the odds of experiencing remission are directly proportional to the amount of weight lost.
Secondly, using a strategy of low-calorie diets and behavioural intervention (allowing ample room for individual preferences) appears feasible in a primary care setting, delivered by health professionals with modest training in obesity management.
Obviously, as anyone who has seen weight loss before is well aware, the challenge in obesity management is more in keeping the weight off than in losing it in the first place. Although sustaining significant weight loss over 12 months is notable, one cannot but wonder how well the participants will do in keeping the weight off in the years to come. This is of course recognised by the researchers, who intend to follow the participants over the next 4 years.
Although a very low calorie diet may not be everyone’s cup of tea, given that the only other intervention that comes anywhere close to the results reported in this paper is bariatric surgery, the findings of this study are indeed notable.
Personally, I would assume that combining the dietary intervention presented in this study with additional pharmacological management may well prove sustainable in the long-term with benefits not just for diabetes control.
I say this because the complex biology of obesity dictates that individuals living with obesity will need a lot more than willpower and hope to sustain meaningful weight loss over time.