So, as Michelle Obama yesterday announced her childhood obesity initiative, another piece of news on childhood obesity crowded the news wires.

This was a study by Sarah Anderson (Ohio State) and Robert Whitaker (Temple) published as an early release in Pediatrics.

The researchers performed a cross-sectional analysis of a nationally representative sample of 8550 four-year-old US children who were assessed in 2005 in the Early Childhood Longitudinal Study.

The study focussed on the relationship between obesity and three household routines: regularly eating the evening meal as a family (>5 nights per week); obtaining adequate nighttime sleep on weekdays (10.5 hours per night); and having limited screen-viewing (television, video, digital video disk) time on weekdays (2 hours/day).

Analyses were adjusted for the child’s race/ethnicity, maternal obesity, maternal education, household income, and living in a single-parent household.

While the prevalence of obesity was 14.3% among children exposed to all 3 routines (14.5% of the sample), it was 24.5% among those exposed to none of the routines (12.4%).

The odds of obesity associated with exposure to all 3, any 2, or only 1 routine (compared with none) were 0.63, 0.64, and 0.84, respectively.

So if you do have kids ask yourself:

1) Do we regularly sit down for supper as a family?
2) Do my kids regularly get at least 10.5 hrs of sleep?
3) Do my kids have less than 2 hrs of screen time on weekdays?

A “no” to all of the above, probably puts your kids in the high-risk category, a “yes” to all of the above, and your kids are probably doing fine.

Now comes the tough part, i.e. wether or not, if you are not doing all of the above, simply doing these three things will actually change your kids risk for obesity. Or in other words, if you did nothing else, except sit down for dinner, have the kids in bed by 8.30, and limit their screen time, would your kids actually have healthy weights?

I am guessing that it will take far more than that. In fact I would not at all be surprised if the families that do any of the above were probably quite different from the families that don’t. I would indeed expect that these families are different in so many ways that really, these three factors are probably just “markers” rather than the actual explanation for the lower obesity risk.

Indeed, if you did have the time and parenting skills to ensure that your whole family sits down for supper, your kids don’t watch too much TV, and are off to bed at bedtime, then you are probably also doing a lot of other things right.

On the other hand, if your family meals are chaotic, you have no control over your kids’ screen time, and they are still running around at midnight, there are probably other issues that need to be addressed.

So while the findings are interesting (and by no means surprising), I am not exactly sure how they will help us address the childhood epidemic.

Perhaps a well-designed intervention study will show wether or not simply adopting these three “routines” will actually make a difference.

I certainly appreciate any comments or opinions on whether or not any of my readers think this will work.

AMS
Hamburg, Germany

What is not shocking is that according to a report on CNN, a US college (Lincoln University, Pennsylvania) has mandated a fitness course that its students have to pass in order to get their degree. 

What is shocking, however, is that only students with a BMI greater than 30, who fail to lose weight during their time at that school are required to take and pass this course.

The underlying assumption of course is that fat people are apparently too stupid to know about healthy eating and exercise and that requiring them to take and pass a course on this will make them drop those excess pounds and become healthy and successful human beings.

Apart from the fact that you would expect college educators to know that wasting resources on well-intended but largely useless weight interventions based solely on “healthy” eating and exercise are not an evidence-base approach to weight management (due to their rather modest effectiveness), assuming that it is even remotely possible to identify individuals in need of “lifestyle education” by simply calculating their BMI (or measuring their waist circumference), is ridiculous.

Perhaps the folks who came up with this idea are unaware of the fact that there is indeed no shortage of “thin” people frequenting fast food restaurants, living sedentary lifestyles or simply using cigarette smoking (if not other drugs), unhealthy dieting, purging, and/or excessive exercise to control their weight.

Singling out students based solely on weight for intervention is nothing else than stereotyping individuals who meet population-based BMI cuttoffs as unhealthy or unfit.

Not only is this discriminatory practice reflective of a limited understanding of the determinants of health, it is also an insult to anyone who’s BMI is greater than 30 despite trying their best to manage their excess weight in this obesogenic environment.

If excess weight is truly affecting a students’ health (and it takes more than a scale or measuring tape to determine this), I have nothing against these students being offered appropriate counseling and interventions by a licensed health professional.

Dictating “lifestyles” to people identified only by virtue of an arbitrarily defined “excess” weight is neither helpful nor supported by scientific evidence.

Perhaps, as one reader comments on the CNN website in response to the college’s response that they are less concerned about health than about the fact that obese students may be less successful in life, “the ones voted as ugly should take a beauty class as this is also related to success”. 

As always, I appreciate any comments on this topic.

AMS
Frankfurt, Germany

p.s. Hat tip to Gabriela Tymowski for drawing my attention to this story

Readers of these pages should by now recognize that obesity is an extraordinarily heterogeneous and complex condition.

While energy balance is simply a matter of energy in and energy out, the determinants of energy in and energy out are anything but simple.

Indeed, the sociopsychobiology of ingestive behaviour is perhaps the most complex of all human behaviours (not surprising given its importance for survival of the species) and the physiological, neuroendocrine and biochemical pathways that determine energy metabolism and activity thermogenesis are clearly no simpler.

It is perhaps, therefore, not all that unexpected when study after study (let alone your own experience) shows that the simplistic formula: “eat less – move more” is so disappointingly ineffective in either preventing or treating excess weight.

Yet, health professionals, decision makers and the general public continue to believe that obesity is simply a matter of “choice”, or in other words, people struggling with excess weight are simply making the wrong choices. Were they only to smarten up and chose differently, their fat would simply melt away – hopefully forever.

The fact that this “simple” formula for maintaining a healthy weight is about as realistic and effective as the “simple” formula for getting rich on the stock market by simply buying low and selling high, apparently does not deter the “healthy living missionaries” from preaching to the uninitiated, who are simply too stupid to understand that weight management is really just a matter of choosing to do the right thing!

Let us for a minute assume that “lifestyle” truly is a major determinant of weight gain (and let us simply ignore the vast body of research on genetics, imprinting, fetal programming, environmental toxins, gut bugs, adipogenic adenoviruses, activated hypothalamic-pituitary adrenal axes, mood and anxiety disorders, addictions, attention deficit, abuse, emotional neglect, poor body image, obesogenic medications and the many other well-documented causes of obesity), then the question remains how much of lifestyle is truly simply a matter of “choice”.

How many of us simply chose sedentary jobs that keep us in front of a computer all day, simply chose to live in neighbourhoods with no sidewalks, simply chose to work in jobs where we earn so little that the only food we can afford to feed our family is crap, simply chose to live so far from work that we face daily hour-long commutes that leave little time for recreational activity (let alone enough sleep), chose to work rather than stay home so we can be around to fix a healthy meal from scratch in time for when the kids come home from school, simply chose to drive a car rather than spend our money on the 5-9 daily servings of fruits and vegetables for everyone in our family, simply chose to have a TV in the house that streams endless hours of advertising to our children, simply chose to drive our kids to school rather than let them cross those five busy intersections, simply chose to live in a country where the government subsidizes corn and meat producers rather than fruit and vegetables growers, etc, etc, etc? Are all of these “lifestyle” factors simply a matter of choice? If yes, then, I am sure we can all simply chose differently and obesity will simply vanish!

But what if obesity is not simply the result of lifestyle “choice” but rather the result of lifestyle “chance”. Do we all truly have a chance to always feed our families healthy foods, have the chance to live in neighbourhoods where it is safe for our kids to walk to school and play outside, have the chance to enroll them in daily sport programs, have the chance to prevent them from ever seeing ads for unhealthy foods, have the chance to ensure that they (and we) get 8 to 9 hours of sound sleep every night, have a chance to convince our politicians to make the right food and environmental policies?

If we don’t, but rather chose to continue living in this obesogenic environment, then do we truly have a chance of not gaining weight? Remember also, that the same environment does not treat everyone fairly – some people (the mutants?) can eat all the junk food they want and stay as thin as a rake, others, despite eating as healthy as possible and despite regular exercise, just keep packing on the pounds.

When it comes to lifestyle’s impact on obesity – is it not far more often a question of CHANCE than of CHOICE?

Let us do our best to first give everyone a fair lifestyle chance and then see if we can perhaps beat the obesity epidemic after all.

AMS
Edmonton, Alberta

Weight gain is the result of positive energy balance and the only way you can get into positive balance is if energy input exceeds output.

As all calories enter the body as food or drink, ingestive behaviour is obviously an important determinant of energy balance.

Although physical activity accounts for only around one-third of total energy expenditure (two-thirds of energy is burnt just to keep your body alive), it is still an important component of energy balance.

It is therefore not surprising when studies find that “eating too much” or “not moving enough” is often (but not always!) associated with weight gain.

This is in fact exactly what was found in a new study by Robert Kushner and SW Choi from the Northwestern University, Chicago, IL, just published in OBESITY.

This study looked at responses to a 53-item lifestyle pattern questionnaire posted on a commercial weight loss program Web site (2004- 2008) in 446,608 adults with an average BMI of 30.5. Categorically, 25.5% were healthy weight, 29.0% were overweight, 33.7% were class I-II obesity, and 11.8% class III obesity.

A stratified random sample was used to estimate the prevalence of 21 lifestyle patterns (7 eating, 7 exercise, and 7 coping: figure) and the odds ratio of the pattern prevalence for each BMI category.

“Unhealthy” lifestyle patterns in diet, exercise, and coping were highly prevalent among the entire population, whereby, the prevalence of these patterns rose with increasing BMI and advancing age.

Gender differences were seen with many of the patterns, most noticeably among the coping patterns. Thus, prevalence of five coping patterns was noticeably higher among women compared to men: emotional eater (41% vs. 29%), self-scrutinizer (negative self-talk) (52% vs. 27%), persistent procrastinator (73% vs. 61%), people pleaser (low self-care) (54% vs. 40%), and doubtful dieter (pessimistic thinking) (41% vs. 29%).

Overall, the lifestyle patterns and terminology used in this study is reminiscent of the “personality types” that Dr. Kushner has described before (see previous blog entry on this).

Based on the current study, the authors conclude that “unhealthy” behavioural patterns are associated with obesity and that behavioural pattern recognition could help identify patients at risk.

For me the paper raises more questions than it answers:

Firstly, I was surprised that despite the significant associations, the effect sizes of individual patterns was actually quite low: this means that a lot of people in the “healthy weight” range apparently also engage in these “unhealthy” behaviours - so why do they not gain weight? Are we missing something?

Secondly, even if these “unhealthy” behaviours are major determinants of weight gain (and not just associations), the real question is what underlies these behaviours - after all, as blogged before, more important than “what someone does” is “why does it” (see Obesity is a Sign, Overeating is a Symptom).

Thus, someone could be a “Couch Champion” because of arthritis, depression, cardio-respiratory disease, low self-efficacy, agorophobia, fibromyalgia, or any number of other reasons that may limit physical activity.

Similarly, the “Meal Skipper” could have attention deficit order, irregular working hours, long commutes, high stress levels or simply false ideas about dieting.

Clearly, to understand obesity, we must move beyond simply describing behaviours to truly understanding the root causes of such behaviours. Any approach to obesity that focuses on behaviours (i.e. “eat less - move more”) while ignoring the key determinants of these behaviours is unlikely to succeed.

AMS
Edmonton, Alberta

    

Diabetes Incidence during DPP

Readers may recall that the original publication showed that in the 2.8 years of intervention, high-risk adults randomised to intensive lifestyle intervention had a risk reduction of 58% in the incidence for type 2 diabetes and a 31% risk reduction with metformin, compared with placebo.

This report now examines whether these effects persist in the long term in 2766 of 3150 (88%) original patients enrolled for a median additional follow-up of 5·7 years. 910 participants were from the lifestyle, 924 from the metformin, and 932 were from the original placebo groups.

While all three groups were offered group-implemented lifestyle intervention, metformin treatment was continued in the original metformin group (850 mg twice daily as tolerated) and the original lifestyle intervention group was offered additional lifestyle support.

During the 10-year follow-up since randomisation to DPP, the original lifestyle group lost, then partly regained weight. In contrast, the metformin group maintained most of the modest weight loss achieved in the first years of the trial.

In contrast to the marked differences in diabetes incidence between groups in the initial study, the incidence of diabetes in this follow-up study were similar between treatment groups: 5·9 per 100 person-years for lifestyle, 4·9 for metformin, and 5·6 for placebo. Interestingly, this finding was not attributable to a rebound effect in the lifestyle group but to a fall in incidence in the placebo and metformin groups that resulted in similar rates as achieved by lifestyle intervention, which changed little throughout follow-up.

Nevertheless, when compared over the 10 years since enrollment in DPP, diabetes incidence was still 34% lower in the lifestyle group and 18% lower in the metformin group than with placebo.

Thus, although the incidence rates of diabetes between the groups began to converge over the 10 year period, the cumulative incidence of diabetes remained lowest in the lifestyle group. The study therefore supports the notion that an intensive lifestyle intervention and metformin can both prevent or delay the incidence of diabetes and that this effect can persist for as long as 10 years.

In an accompanying editorial, my Indian friend and colleague Anoop Misra, about whom I have blogged previously, comments:

“Prevention of diabetes is a long and winding road. There seems to be no short cut, and a persistent and prolonged intensive lifestyle intervention seems to be the most effective mode to travel on it. However, more research needs to be done with dietary (eg, high-fibre, low-glycaemic-index foods), physical activity (aerobic plus resistance exercise), and pharmaceutical (especially glucagon-like peptide-based therapies) manipulations to prevent diabetes. We need more effective drugs for those who cannot follow intensive lifestyle therapy because of infirmity. Because of the high prevalence and rapid increase in the metabolic syndrome and diabetes, there is a need to apply these findings to, and generate data from, other ethnic groups and developing countries.”

It may be worthwhile to point out that over the 10 years, there was virtually no weight loss or weight gain in the groups - essentially at the end what all groups had was weight stabilisation. Readers will note that I have previously blogged about the importance of preventing weight gain rather than focussing all efforts on weight loss - especially when it comes to prevention. This is in fact what we recommend for both Edmonton Obesity Stage 0 and 1 patients.

AMS
Seoul, Korea