Dr. Sharma's Obesity Notes

As not everyone may have a chance during the week to read every post, here’s a roundup of last week’s posts:

• Will Losing Weight Make You Fat?
• Is It Time To Abandon The Notion of Personal Choice In Dietary Counseling?
• Bariatric Surgery Reduces Response to Food Cues?
• Gastric Bypass Reduces Appetite for Fat?
• Stretching Beats Walking to Prevent Complictions of Pregnancy?

Have a great Sunday! (or what’s left of it)

AMS
Edmonton, Alberta

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Weight loss is a multi-billion dollar industry, which, if it actually worked, should have put itself out of business by now.

Of course, anyone, who has ever lost weight (including probably patients who have been through our program), realises that losing weight is one thing - unfortunately, keeping it off is a whole different story.

So all that really counts in any program should be how patients do in the long term and how much weight (if any) participants can actually keep off.

Even more important perhaps would be the question whether clients actually get any healthier (if they do, then what ultimately happens to weight may not really matter that much).

I would argue that even more importantly, weight management programs should, if possible address the root cause of the problem (eating too much is a symptom, not a diagnosis!).

As my readers are well aware, there is certainly a wide range of commercial weight loss programs, services and products to chose from - while some have solid science and considerable evidence behind them, others promise quick and easy results that defy scientific rationale and good medical practice.

So how is the consumer to decide?

Some guidance is provided on Alberta’s MyHealth website, which has the following recommendations to offer (adapted):

Questions to ask before joining a weight loss program:

• Does the program provide counselling to help me change my eating activities and personal habits?
• Is the staff made up of qualified counsellors and health professionals, such as nutritionists, registered dietitians, doctors, nurses, psychologists, and exercise physiologists?
• Is training available on how to deal with times when I may feel stressed and slip back into old habits?
• Is attention paid to keeping the weight off? How long is this phase?
• Are food choices flexible and suitable?
• Are weight goals set with the help of a health professional?
• What percentage of people complete the program?
• What is the average weight loss among people who finish the program?
• What percentage of people have problems or side effects? What are the problems and side effects?
• Are there fees or costs for additional items, such as dietary supplements?

In addition programs should provide information on:

• The program and the staff qualifications, including a description of the program content and goals and information about the weight management training, experience, certification, and education of the staff.
• The risks associated with being overweight or obese and the potential benefits of modest weight loss.
• The risks associated with the product or program, such as with the program itself or any drugs, devices, dietary supplements, or exercise plans used in the treatment.
• The information should specify when to talk to a health professional and how much weight is healthy to lose and should explain that a very low-calorie diet may be harmful.
• Costs, including total program costs, attendance fees, re-entry fees, medical tests, and any nonrefundable costs.
• The success of the program, such as what percentage of clients meet their weight-loss goals, how much weight they lose, and how long they maintained their new weight.

The key of course is not to just accept boiler plate answers but to question those answers and do your own research on the claims and credentials of the program.

Remember - if it sound’s too good to be true - it is probably a lie!

I would certainly love to hear from my readers on how they were misinformed or duped by commercial weight loss programs - please do not name specific programs but rather describe in general terms some of the experiences you may have had with program X, Y, or Z in the past and the reasons why you think you fell for it.

I’d also be interested in any additional tips and rules that my readers may wish to propose on finding an appropriate program.

AMS
Edmonton, Alberta

Reader of these pages are probably well aware of the countless supplements, potions, pills, and other products being enthusiastically advertised (and sold) for weight loss.

Although this is a billion dollar market, most users of these products (after spending a fortune) will have realised that virtually none of them hold any of the advertised promises (viz. boosts your metabolism, burns fat, reduces appetite, abolishes hunger, shaves inches off your waistline, etc.).

Apparently, this is not just YOU for whom these products do not work - it turns out that the published scientific evidence (by no means available for all such products) is rather light (pun intended!).

Thus, a recent review of reviews on the evidence in support of such weight-loss supplements, published by Igho Onakpoya and colleagues from the University of Exeter, UK, in a recent issue of OBESITY, concludes that:

“…the existing systematic reviews of clinical trials testing the efficacy of food supplements in reducing body weight fail to provide good evidence that any of these preparations generate clinically relevant weight loss without undue risks.”

For their paper, the researchers conducted an extensive search of all relevant databases to identify review articles summarizing the data on individual weight-loss supplements.

Published reviews that met the eligibility and quality criteria were available only for the following supplements with rather modest (not to say non-existent) findings:

Guar gum: 20 randomized controlled trials (RCTs) including 366 participants: not efficacious for reducing body weight.

Chromium picolinate: 17 RCTs with 961 participants: a “relatively small” effect in reducing weight.

Ephedra: 17 RCTs with 1,451 participants: a significant short-term effect on body weight. Serious risks of Ephedra/ephedrine intake were also identified.

Citrus aurantium (bitter orange): 1 clinical trial with 23 participants: no significant effect on body weight.

Conjugated linoleic acid: 21 clinical trials with 852 participants: no significant effect on body weight.

Calcium: 13 RCTs with a total of 1,127 participants: no significant effect on body weight.

Glucomannan: 14 RCTs with 531 participants: significant (albeit small) reduction in body weight.

Chitosan: 15 RCTs with 1,219 participants: some evidence of short-term weight loss in obese and overweight individuals.

Camellia sinensis (green tea): 15 trials with 1,226 participants: efficacious for short-term weight reduction and weight maintenance.

Overall the authors come to the rather sobering conclusions that:

“Generally speaking, the results and conclusions of the systematic reviews are disappointing. In particular, they are limited by the often small sample sizes and low quality of the primary studies, and by the fact that some of them fail to control for lifestyle variables with important influence on body weight.”

The authors also don’t appear happy with the quality of the reviews:

“…several of the systematic reviews are flawed, for instance, through insufficient search strategies or a failure to account for the methodological quality of the primary studies. Systematic reviews that reported a “statistically significant effect” are limited by small effect sizes (e.g., chromium picolinate), and/or a high risk of adverse events (e.g., Ephedra). Clinically significant weight loss of at least 5% of body weight was not achieved. The short duration of most of the primary studies is a further drawback. Therefore, none of the nine food supplements discussed above are supported by sound evidence from systematic reviews for generating clinically relevant effects on body weight without undue risks.”

Not that any of this is likely to cut into the profits of the “all-natural” weight-loss supplement market - after all it is hard to get people to stop spending their hard-earned dollars on hope (and of course, it is their money to spend).

Nevertheless, this is the kind of information that is likely to be available to Canadians through the COACH initiative.

I know I could be opening a can of worms by asking my readers to share their insights and experience with weight-loss supplements but I am guessing that other readers will probably find this of interest.

AMS
Edmonton, Alberta

Onakpoya IJ, Wider B, Pittler MH, & Ernst E (2011). Food supplements for body weight reduction: a systematic review of systematic reviews. Obesity (Silver Spring, Md.), 19 (2), 239-44 PMID: 20814412

Losing weight and keeping it off, for most people, means reducing their caloric intake and maintaing a calorie-reduced diet for as long as they plan to keep the weight off (a rare few can depend exclusively on exercise alone to lose and keep weight off - most of us can’t).

This means, they will either have to restrict their daily calories by basing their food choices on their total caloric content or by depending on someone else to providing them with meals that contain fewer calories than what they would normally eat (meal replacements or prepackaged meals).

The latter approach was now, for the first time, tested in a randomised clinical trial.

In a paper by Cheryl Rock and colleagues from San Diego, Tucson, Minneapolis and Portland, published last month in JAMA, the investigators studied the effect of a free prepared meal and incentivized weight-loss program on weight loss and weight loss maintenance in obese and overweight women.

A total of 442 women (BMI 25-40) aged 18 to 69 years were randomised to one of three two-year interventions:

1) A “usual care” group, where participants were provided consultation with a research staff dietetics professional, who provided publicly available print material that described dietary and physical activity guidelines to promote weight loss and maintenance at baseline and again at 6 months. Sample meal plans, recommendations to increase physical activity, and written materials and resources for strategies and skills (eg, reading food labels, estimating serving sizes, eating outside the home) were provided. This 1-hour session was followed by monthly check-in via e-mail or telephone, and progress and strategies were discussed in a follow-up counseling session at 6 months.

2) An “in-centre” group, where participants were offered free-of-charge weekly one-to-one counseling sessions, with follow-up telephone and e-mail contacts and Web site or message board availability. Program materials included free-of-charge prepackaged prepared foods as needed to achieve a meal plan.

3) An “telephone” group, where all counseling was conducted by phone, but the participants received exactly the same foods and program support as provided to group 2.

In groups 2 and 3, participants were encouraged during the initial period to follow a menu plan with prepackaged foods, which would provide 42% to 68% of energy. Over time, participants were transitioned to a meal plan based mainly on food not provided by the program, although participants could choose to include 1 prepackaged meal per day during weight loss maintenance.

Participants in groups 2 and 3 were also counseled to increase physical activity to 30 minutes of physical activity on 5 or more days per week.

The study was entirely funded and all prepackaged meals and program materials were provided free of charge by Jenny Craig.

It is perhaps also important to note that, although more than 90% of participants completed the study, only 24.6% of center-based and 39.2% of telephone-based participants continued with their weekly counseling sessions during the last six months of the study.

At the end of two years, the participants in the “usual-care” group had lost 2.0 kg (2.1% of their initial weight).

In contrast, the participants in the “in-centre” and “telephone” groups lost 7.4 kg (7.9%) and 6.2Kg (6.8%), respectively.

Thus, there is no doubt that the “Jenny-Craig” foods and programs were far more effective than the “usual-care” intervention.

However, as the authors point out, an important caveat is that although the participants in groups 2 and 3 of this trial followed the Jenny Craig program and received the prepackaged foods, all of this was provided to them free of charge.

The costs to paying participants would normally have included the $359 annual enrollment fees for a year-long premium plus membership in Jenny Craig as well as the the cost of Jenny Craig’s prepackaged food, which averages $100 per week. An additional $20 to $25 per week would have been needed for the recommended vegetables, and dairy foods. Thus, the first year would have cost participants around $4000 in foods.

For the second year of the program, when participants transitioned to their own foods, food costs would have averaged about $2200 for the year. Surprisingly, perhaps, these figures are not that much more than the estimated $124 per week that US consumers typically spend on food according to the Consumer Expenditure Survey.

Nevertheless, as the authors note, there may be:

“…a major issue is the generalizability of these findings to the average patient. The results may be related in part to the economic benefits to the participants of providing food, as well as reimbursement for participating in clinic visits, and the low dropout rate in this study contrasts with the high attrition rates reported among weight loss program cohorts.“

Nevertheless, the study demonstrates that the provision of (free) prepackaged meals together with (free) weekly in-person or telephone visits and (free) program materials are clearly more effective in helping patients achieve and maintain a clinically meaningful amount of weight than “usual” care.

Whether subjects were able to maintain any of this weight loss after discontinuing the trial and whether or not any of the participants were convinced enough of the value of the program to become paying customers of Jenny Craig is of course not mentioned in the sutdy.

But I am sure that the researchers are fully aware that It will be of considerable interest to check in again with the participants in this trial in a couple of years to see if there are any lasting or carry-over effects from the participation in this trial.

Whether or not this happens, I would certainly like to commend Jenny Craig on funding this study - this is not something that can be said for most commercial programs, which are often happier to rely on “before and after testimonial” (these results may not be typical) than on randomised controlled trials and peer-reviewed publications to market their services.

AMS
Edmonton, Alberta

Rock CL, Flatt SW, Sherwood NE, Karanja N, Pakiz B, & Thomson CA (2010). Effect of a free prepared meal and incentivized weight loss program on weight loss and weight loss maintenance in obese and overweight women: a randomized controlled trial. JAMA : the journal of the American Medical Association, 304 (16), 1803-10 PMID: 20935338

Was Gandhi older or younger than nine when he died?

This is obviously a stupid question. Of course you know that Gandhi must have been older than nine when he lead India to independence.

So what has this question to do with anything?

Yesterday, on my way to Whitehorse in the Yukon, where I am advising my Yukon colleagues on better managing their obese patients, I picked up “Risk”, a book by the Ottawa journalist Dan Gardner, which deals with the issue of why we fear things we shouldn’t.

Much of what’s in the book has to do with basic human psychology and how we process and respond to bits of information with our guts rather than our heads.

The Gandhi question comes from an example in Gardner’s book. Of course we all know that Gandhi did not die before the age of nine, so seriously, guess how old he really could have been when he was assassinated?

It turns out that in carefully conducted experiments by the German psychologists Fritz Strak and Thomas Mussweiler, in which people were first asked the nonsense “nine” question and then asked to try and guess how old they thought Gandhi really was when he died, their average guess was around 50.

Strak and Mussweiler then asked another set of volunteers the “nonsense” question, but this time it was whether they thought that Gandhi died before or after age 140. Then after agreeing that this was indeed nonsense, the participants were asked to seriously think about how old he might have been – this time around, their answer was 67.

So simply by throwing a ridiculously low number out there, the researchers apparently made people guess a lower age than by throwing out a ridiculously high number, despite the fact that in both cases the first number could obviously not have been true.

This experiment, as do many others in the psychology literature, illustrate a phenomenon Gardner refers to as the ‘Anchoring Rule’. This rule describes our natural tendency to be influenced in our judgment by numbers even when we fully know they are ridiculous or even have absolutely nothing to do with the issue at hand.

Of course we know Gandhi could not have been nine when he died, so he must have been older – and we quickly try to recall images of him and all the stuff he did and try to make a reasonable guess – namely perhaps around 50 or so? So we are making adjustments for what we know to be wrong and come up with a number that we think is more likely.

When we start with 140, we know this is ridiculously high and of course Gandhi must have been much younger when he died and immediately, we call up exactly the same mental image of Gandhi and think of all he accomplished and in the end estimate that he could well have been, say, in his late sixties when he died.

In both cases we are starting with numbers we know are definitely wrong and are correcting them to something we consider more reasonable. Once we’ve heard the number ‘nine’ we underestimate the possible age of death. In contrast, once we’ve heard the number ‘140’, our guesstimate is much higher.

So how does this relate to testimonials and weight loss expectations?

We’ve all seen the commercials with testimonials from people who have lost an incredible amount of weight (say 250 lbs), often in a ridiculously short amount of time (say 3 months), with virtually no effort (say just by taking the super-expensive ‘all-natural’ supplements).

Ok, so we all know that this, even if remotely true, is probably the best result ever and because we know that the company wants to sell us their product or service, they are probably presenting their best case (in fact they’ll will happily state on their ad that this result may not be typical).

So we make adjustments – yeah, maybe if I join I’ll not lose 250 lbs (because I know that’s ridiculous) but, hey, maybe I’ll lose 60 or maybe even only 40 lbs. And of course I know that 3 months is an unrealistic time frame, so I mentally readjust this number to, let’s say, 6 months. And yes, of course, it’s not just taking the pills that’ll make this happen, sure, I’ll probably also have to make some lifestyle changes like eat healthier and perhaps do a few minutes of exercise everyday, because of course I know there’s so such thing as ‘magical’ supplements.

But you know what – 40 lbs in 6 months with healthy eating and a bit of exercise, that sounds reasonable and if the supplements can help me do that, then maybe $199 a month (first month free!) is perhaps not such a bad deal – so, now that I have seen through the ad and have reasonably adjusted my expectations, where can I order this stuff?

This is exactly how the Anchoring Rule works – despite being very cautious and reasonable, it works every time – even in the smartest and most cautious people!

Indeed, the power of testimonials is so compellingly effective and misleading, that it is in fact illegal for doctors in Canada to use patient testimonials to promote their services, even if these testimonials are completely honest and true!

This is why, by law, I am prohibited from posting any of the many comments that I receive from former patients who have successfully managed their weight problem and want to personally thank me by posting their success stories on my blog.

But of course, what applies to me as a regulated health professional, does not apply to any of the commercial weight loss programs that can bombard you with all kinds of success stories and testimonials, the more unrealistic and wildly atypical, the better for their sales.

Thanks to the Anchoring Rule, even the most ridiculous success story, after reasonable adjustment, will still sound convincing enough to make you risk spending a few bucks.

So, the next time you read a wildly enthusiastic weight loss testimonial and consider signing up, simply ask yourself – could Gandhi really have died before he turned nine?

AMS
Whitehorse, Yukon